idnits 2.17.1 draft-ietf-lmap-framework-11.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (February 22, 2015) is 3344 days in the past. Is this intentional? Checking references for intended status: Informational ---------------------------------------------------------------------------- -- Looks like a reference, but probably isn't: '0' on line 256 -- Looks like a reference, but probably isn't: '180' on line 256 == Missing Reference: 'Cycle-ID' is mentioned on line 1067, but not defined == Outdated reference: A later version (-24) exists of draft-ietf-ippm-metric-registry-02 == Outdated reference: A later version (-18) exists of draft-ietf-lmap-information-model-03 Summary: 0 errors (**), 0 flaws (~~), 4 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group P. Eardley 3 Internet-Draft BT 4 Intended status: Informational A. Morton 5 Expires: August 26, 2015 AT&T Labs 6 M. Bagnulo 7 UC3M 8 T. Burbridge 9 BT 10 P. Aitken 11 Brocade 12 A. Akhter 13 LiveAction 14 February 22, 2015 16 A framework for Large-Scale Measurement of Broadband Performance (LMAP) 17 draft-ietf-lmap-framework-11 19 Abstract 21 Measuring broadband service on a large scale requires a description 22 of the logical architecture and standardisation of the key protocols 23 that coordinate interactions between the components. The document 24 presents an overall framework for large-scale measurements. It also 25 defines terminology for LMAP (Large-Scale Measurement of Broadband 26 Performance). 28 Status of This Memo 30 This Internet-Draft is submitted in full conformance with the 31 provisions of BCP 78 and BCP 79. 33 Internet-Drafts are working documents of the Internet Engineering 34 Task Force (IETF). Note that other groups may also distribute 35 working documents as Internet-Drafts. The list of current Internet- 36 Drafts is at http://datatracker.ietf.org/drafts/current/. 38 Internet-Drafts are draft documents valid for a maximum of six months 39 and may be updated, replaced, or obsoleted by other documents at any 40 time. It is inappropriate to use Internet-Drafts as reference 41 material or to cite them other than as "work in progress." 43 This Internet-Draft will expire on August 26, 2015. 45 Copyright Notice 47 Copyright (c) 2015 IETF Trust and the persons identified as the 48 document authors. All rights reserved. 50 This document is subject to BCP 78 and the IETF Trust's Legal 51 Provisions Relating to IETF Documents 52 (http://trustee.ietf.org/license-info) in effect on the date of 53 publication of this document. Please review these documents 54 carefully, as they describe your rights and restrictions with respect 55 to this document. Code Components extracted from this document must 56 include Simplified BSD License text as described in Section 4.e of 57 the Trust Legal Provisions and are provided without warranty as 58 described in the Simplified BSD License. 60 Table of Contents 62 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 63 2. Outline of an LMAP-based measurement system . . . . . . . . . 5 64 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 9 65 4. Constraints . . . . . . . . . . . . . . . . . . . . . . . . . 12 66 4.1. The measurement system is under the direction of a single 67 organisation . . . . . . . . . . . . . . . . . . . . . . 13 68 4.2. Each MA may only have a single Controller at any point in 69 time . . . . . . . . . . . . . . . . . . . . . . . . . . 13 70 5. Protocol Model . . . . . . . . . . . . . . . . . . . . . . . 13 71 5.1. Bootstrapping process . . . . . . . . . . . . . . . . . . 14 72 5.2. Control Protocol . . . . . . . . . . . . . . . . . . . . 15 73 5.2.1. Configuration . . . . . . . . . . . . . . . . . . . . 15 74 5.2.2. Instruction . . . . . . . . . . . . . . . . . . . . . 16 75 5.2.3. Capabilities, Failure and Logging Information . . . . 20 76 5.3. Operation of Measurement Tasks . . . . . . . . . . . . . 21 77 5.3.1. Starting and Stopping Measurement Tasks . . . . . . . 22 78 5.3.2. Overlapping Measurement Tasks . . . . . . . . . . . . 23 79 5.4. Report Protocol . . . . . . . . . . . . . . . . . . . . . 23 80 5.4.1. Reporting of Subscriber's service parameters . . . . 25 81 5.5. Operation of LMAP over the underlying packet transfer 82 mechanism . . . . . . . . . . . . . . . . . . . . . . . . 25 83 5.6. Items beyond the scope of the initial LMAP work . . . . . 26 84 5.6.1. End-user-controlled measurement system . . . . . . . 28 85 6. Deployment considerations . . . . . . . . . . . . . . . . . . 28 86 6.1. Controller and the measurement system . . . . . . . . . . 28 87 6.2. Measurement Agent . . . . . . . . . . . . . . . . . . . . 29 88 6.2.1. Measurement Agent on a networked device . . . . . . . 30 89 6.2.2. Measurement Agent embedded in site gateway . . . . . 30 90 6.2.3. Measurement Agent embedded behind site NAT /firewall 30 91 6.2.4. Multi-homed Measurement Agent . . . . . . . . . . . . 30 92 6.2.5. Measurement Agent embedded in ISP network . . . . . . 31 94 6.3. Measurement Peer . . . . . . . . . . . . . . . . . . . . 31 95 6.4. Deployment examples . . . . . . . . . . . . . . . . . . . 32 96 7. Security considerations . . . . . . . . . . . . . . . . . . . 35 97 8. Privacy considerations . . . . . . . . . . . . . . . . . . . 37 98 8.1. Categories of entities with information of interest . . . 37 99 8.2. Examples of sensitive information . . . . . . . . . . . . 38 100 8.3. Different privacy issues raised by different sorts of 101 Measurement Methods . . . . . . . . . . . . . . . . . . . 39 102 8.4. Privacy analysis of the communication models . . . . . . 40 103 8.4.1. MA Bootstrapping . . . . . . . . . . . . . . . . . . 40 104 8.4.2. Controller <-> Measurement Agent . . . . . . . . . . 41 105 8.4.3. Collector <-> Measurement Agent . . . . . . . . . . . 42 106 8.4.4. Measurement Peer <-> Measurement Agent . . . . . . . 42 107 8.4.5. Measurement Agent . . . . . . . . . . . . . . . . . . 44 108 8.4.6. Storage and reporting of Measurement Results . . . . 45 109 8.5. Threats . . . . . . . . . . . . . . . . . . . . . . . . . 45 110 8.5.1. Surveillance . . . . . . . . . . . . . . . . . . . . 45 111 8.5.2. Stored data compromise . . . . . . . . . . . . . . . 45 112 8.5.3. Correlation and identification . . . . . . . . . . . 46 113 8.5.4. Secondary use and disclosure . . . . . . . . . . . . 46 114 8.6. Mitigations . . . . . . . . . . . . . . . . . . . . . . . 47 115 8.6.1. Data minimisation . . . . . . . . . . . . . . . . . . 47 116 8.6.2. Anonymity . . . . . . . . . . . . . . . . . . . . . . 48 117 8.6.3. Pseudonymity . . . . . . . . . . . . . . . . . . . . 49 118 8.6.4. Other mitigations . . . . . . . . . . . . . . . . . . 49 119 9. IANA considerations . . . . . . . . . . . . . . . . . . . . . 50 120 10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 50 121 11. History . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 122 11.1. From -00 to -01 . . . . . . . . . . . . . . . . . . . . 50 123 11.2. From -01 to -02 . . . . . . . . . . . . . . . . . . . . 51 124 11.3. From -02 to -03 . . . . . . . . . . . . . . . . . . . . 52 125 11.4. From -03 to -04 . . . . . . . . . . . . . . . . . . . . 52 126 11.5. From -04 to -05 . . . . . . . . . . . . . . . . . . . . 53 127 11.6. From -05 to -06 . . . . . . . . . . . . . . . . . . . . 54 128 11.7. From -06 to -07 . . . . . . . . . . . . . . . . . . . . 54 129 11.8. From -07 to -08 . . . . . . . . . . . . . . . . . . . . 54 130 11.9. From -08 to -09 . . . . . . . . . . . . . . . . . . . . 54 131 11.10. From -09 to -10 . . . . . . . . . . . . . . . . . . . . 54 132 11.11. From -10 to -11 . . . . . . . . . . . . . . . . . . . . 55 133 12. Informative References . . . . . . . . . . . . . . . . . . . 55 134 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 57 136 1. Introduction 138 There is a desire to be able to coordinate the execution of broadband 139 measurements and the collection of measurement results across a large 140 scale set of Measurement Agents (MAs). These MAs could be software 141 based agents on PCs, embedded agents in consumer devices (such as TVs 142 or gaming consoles), embedded in service provider controlled devices 143 such as set-top boxes and home gateways, or simply dedicated probes. 144 MAs may also be embedded on a device that is part of an ISP's 145 network, such as a DSLAM (Digital Subscriber Line Access 146 Multiplexer), router, Carrier Grade NAT (Network Address Translator) 147 or ISP Gateway. It is expected that a measurement system could 148 easily encompass a few hundred thousand or even millions of such MAs. 149 Such a scale presents unique problems in coordination, execution and 150 measurement result collection. Several use cases have been proposed 151 for large-scale measurements including: 153 o Operators: to help plan their network and identify faults 155 o Regulators: to benchmark several network operators and support 156 public policy development 158 Further details of the use cases can be found in 159 [I-D.ietf-lmap-use-cases]. The LMAP framework should be useful for 160 these, as well as other use cases, such as to help end users run 161 diagnostic checks like a network speed test. 163 The LMAP Framework has three basic elements: Measurement Agents, 164 Controllers and Collectors. 166 Measurement Agents (MAs) initiate the actual measurements, which are 167 called Measurement Tasks in the LMAP terminology. In principle, 168 there are no restrictions on the type of device in which the MA 169 function resides. 171 The Controller instructs one or more MAs and communicates the set of 172 Measurement Tasks an MA should perform and when. For example it may 173 instruct a MA at a home gateway: "Measure the 'UDP latency' with 174 www.example.org; repeat every hour at xx.05". The Controller also 175 manages a MA by instructing it how to report the Measurement Results, 176 for example: "Report results once a day in a batch at 4am". We refer 177 to these as the Measurement Schedule and Report Schedule. 179 The Collector accepts Reports from the MAs with the Results from 180 their Measurement Tasks. Therefore the MA is a device that gets 181 Instructions from the Controller, initiates the Measurement Tasks, 182 and reports to the Collector. The communications between these three 183 LMAP functions are structured according to a Control Protocol and a 184 Report Protocol. 186 The desirable features for a large-scale Measurement Systems we are 187 designing for are: 189 o Standardised - in terms of the Measurement Tasks that they 190 perform, the components, the data models and protocols for 191 transferring information between the components. Amongst other 192 things, standardisation enables meaningful comparisons of 193 measurements made of the same metric at different times and 194 places, and provides the operator of a Measurement System with 195 criteria for evaluation of the different solutions that can be 196 used for various purposes including buying decisions (such as 197 buying the various components from different vendors). Today's 198 systems are proprietary in some or all of these aspects. 200 o Large-scale - [I-D.ietf-lmap-use-cases] envisages Measurement 201 Agents in every home gateway and edge device such as set-top boxes 202 and tablet computers, and located throughout the Internet as well 203 [I-D.ietf-ippm-lmap-path]. It is expected that a Measurement 204 System could easily encompass a few hundred thousand or even 205 millions of Measurement Agents. Existing systems have up to a few 206 thousand MAs (without judging how much further they could scale). 208 o Diversity - a Measurement System should handle Measurement Agents 209 from different vendors, that are in wired and wireless networks, 210 can execute different sorts of Measurement Task, are on devices 211 with IPv4 or IPv6 addresses, and so on. 213 2. Outline of an LMAP-based measurement system 215 In this section we provide an overview of the whole Measurement 216 System. New LMAP-specific terms are capitalised; Section 3 provides 217 a terminology section with a compilation of all the LMAP terms and 218 their definition. Section 4 onwards considers the LMAP components in 219 more detail. 221 Other LMAP specifications will define an information model, the 222 associated data models, and select/extend one or more protocols for 223 the secure communication: firstly, a Control Protocol, from a 224 Controller to instruct Measurement Agents what performance metrics to 225 measure, when to measure them, how/when to report the measurement 226 results to a Collector; secondly, a Report Protocol, for a 227 Measurement Agent to report the results to the Collector. 229 Figure 1 shows the main components of a Measurement System, and the 230 interactions of those components. Some of the components are outside 231 the scope of initial LMAP work. 233 The MA performs Measurement Tasks. In the example shown in Figure 1, 234 the MA is observing existing traffic. Another possibility is for the 235 MA to generate (or receive) traffic specially created for the purpose 236 and measure some metric associated with its transfer. The 237 Appendix shows some examples of possible arrangements of the 238 components. 240 The MAs are pieces of code that can be executed in specialised 241 hardware (hardware probe) or on a general-purpose device (like a PC 242 or mobile phone). A device with a Measurement Agent may have 243 multiple physical interfaces (Wi-Fi, Ethernet, DSL (Digital 244 Subscriber Line); and non-physical interfaces such as PPPoE (Point- 245 to-Point Protocol over Ethernet) or IPsec) and the Measurement Tasks 246 may specify any one of these. 248 The Controller manages a MA through use of the Control Protocol, 249 which transfers the Instruction to the MA. This describes the 250 Measurement Tasks the MA should perform and when. For example the 251 Controller may instruct a MA at a home gateway: "Count the number of 252 TCP SYN packets observed in a 1 minute interval; repeat every hour at 253 xx.05 + Unif[0,180] seconds". The Measurement Schedule determines 254 when the Measurement Tasks are executed. The Controller also manages 255 a MA by instructing it how to report the Measurement Results, for 256 example: "Report results once a day in a batch at 4am + Unif[0,180] 257 seconds; if the end user is active then delay the report 5 minutes". 258 The Report Schedule determines when the Reports are uploaded to the 259 Collector. The Measurement Schedule and Report Schedule can define 260 one-off (non-recurring) actions ("Do measurement now", "Report as 261 soon as possible"), as well as recurring ones. 263 The Collector accepts a Report from a MA with the Measurement Results 264 from its Measurement Tasks. It then provides the Results to a 265 repository (see below). 267 A Measurement Method defines how to measure a Metric of interest. It 268 is very useful to standardise Measurement Methods, so that it is 269 meaningful to compare measurements of the same Metric made at 270 different times and places. It is also useful to define a registry 271 for commonly-used Metrics [I-D.ietf-ippm-metric-registry] so that a 272 Metric with its associated Measurement Method can be referred to 273 simply by its identifier in the registry. The registry will 274 hopefully be referenced by other standards organisations. The 275 Measurement Methods may be defined by the IETF, locally, or by some 276 other standards body. 278 Broadly speaking there are two types of Measurement Method. In both 279 types a Measurement Agent measures a particular Observed Traffic 280 Flow. It may involve a single MA simply observing existing traffic - 281 for example, the Measurement Agent could count bytes or calculate the 282 average loss for a particular flow. On the other hand, a Measurement 283 Method may involve multiple network entities, which perform different 284 roles. For example, a "ping" Measurement Method, to measure the 285 round trip delay , would consist of an MA sending an ICMP (Internet 286 Control Message Protocol) ECHO request to a responder in the 287 Internet. In LMAP terms, the responder is termed a Measurement Peer 288 (MP), meaning that it helps the MA but is not managed by the 289 Controller. Other Measurement Methods involve a second MA, with the 290 Controller instructing the MAs in a coordinated manner. Traffic 291 generated specifically as part of the Measurement Method is termed 292 Measurement Traffic; in the ping example, it is the ICMP ECHO 293 Requests and Replies. The protocols used for the Measurement Traffic 294 are out of the scope of initial LMAP work, and fall within the scope 295 of other IETF WGs such as IPPM (IP Performance Metrics). 297 A Measurement Task is the action performed by a particular MA at a 298 particular time, as the specific instance of its role in a 299 Measurement Method. LMAP is mainly concerned with Measurement Tasks, 300 for instance in terms of its Information Model and Protocols. 302 For Measurement Results to be truly comparable, as might be required 303 by a regulator, not only do the same Measurement Methods need to be 304 used to assess Metrics, but also the set of Measurement Tasks should 305 follow a similar Measurement Schedule and be of similar number. The 306 details of such a characterisation plan are beyond the scope of work 307 in IETF although certainly facilitated by IETF's work. 309 Both control and report messages are transferred over a secure 310 Channel. A Control Channel is between the Controller and a MA; the 311 Control Protocol delivers Instruction Messages to the MA and 312 Capabilities, Failure and Logging Information in the reverse 313 direction. A Report Channel is between a MA and Collector, and the 314 Report Protocol delivers Reports to the Collector. 316 Finally we introduce several components that are outside the scope of 317 initial LMAP work and will be provided through existing protocols or 318 applications. They affect how the Measurement System uses the 319 Measurement Results and how it decides what set of Measurement Tasks 320 to perform. As shown in Figure 1, these components are: the 321 bootstrapper, Subscriber parameter database, data analysis tools, and 322 Results repository. 324 The MA needs to be bootstrapped with initial details about its 325 Controller, including authentication credentials. The LMAP work 326 considers the bootstrap process, since it affects the Information 327 Model. However, LMAP does not define a bootstrap protocol, since it 328 is likely to be technology specific and could be defined by the 329 Broadband Forum, CableLabs or IEEE depending on the device. Possible 330 protocols are SNMP (Simple Network Management Protocol), NETCONF 331 (Network Configuration Protocol) or (for Home Gateways) CPE WAN 332 Management Protocol (CWMP) from the Auto Configuration Server (ACS) 333 (as specified in TR-069 [TR-069]). 335 A Subscriber parameter database contains information about the line, 336 such as the customer's broadband contract (perhaps 2, 40 or 80Mb/s), 337 the line technology (DSL or fibre), the time zone where the MA is 338 located, and the type of home gateway and MA. These parameters are 339 already gathered and stored by existing operations systems. They may 340 affect the choice of what Measurement Tasks to run and how to 341 interpret the Measurement Results. For example, a download test 342 suitable for a line with an 80Mb/s contract may overwhelm a 2Mb/s 343 line. 345 A Results repository records all Measurement Results in an equivalent 346 form, for example an SQL (Structured Query Language) database, so 347 that they can easily be accessed by the data analysis tools. 349 The data analysis tools receive the results from the Collector or via 350 the Results repository. They might visualise the data or identify 351 which component or link is likely to be the cause of a fault or 352 degradation. This information could help the Controller decide what 353 follow-up Measurement Task to perform in order to diagnose a fault. 354 The data analysis tools also need to understand the Subscriber's 355 service information, for example the broadband contract. 357 +-----------+ +-----------+ ^ 358 |End user or| |End user or| | 359 |Measurement| |Measurement| Non-LMAP 360 | Peer | | Peer | Scope 361 +-----------+ +-----------+ v 362 ^ Observed ^ ^ 363 \ traffic flow +-------------+ / / ^ 364 \...............|.............|..../ / | 365 | Measurement |........../ | 366 +----------------->| Agent | Measurement traffic | 367 | +-------------+ | 368 | ^ | | 369 | Instruction | | Report | 370 | (over Control | | (over Report Channel) | 371 | Channel) | +---------------+ | 372 | | | | 373 | | | | 374 | | v LMAP 375 | +------------+ +------------+ Scope 376 | | Controller | | Collector | | 377 | +------------+ +------------+ v 378 | ^ ^ | ^ 379 | | | | | 380 | | +-------+ | | 381 | | | v | 382 +------------+ +----------+ +--------+ +----------+ | 383 |Bootstrapper| |Subscriber|--->| data |<---| Results | Out 384 +------------+ |parameter | |analysis| |repository| of 385 |database | | tools | +----------+ Scope 386 +----------+ +--------+ | 387 | 388 v 390 Schematic of main elements of an LMAP-based Measurement System 391 (showing the elements in and out of the scope of initial LMAP work) 393 3. Terminology 395 This section defines terminology for LMAP. Please note that defined 396 terms are capitalized. 398 Bootstrap: A process that integrates a Measurement Agent into a 399 Measurement System. 401 Capabilities: Information about the performance measurement 402 capabilities of the MA, in particular the Measurement Method roles 403 and measurement protocol roles that it can perform, and the device 404 hosting the MA, for example its interface type and speed, but not 405 dynamic information. 407 Channel: A bi-directional logical connection that is defined by a 408 specific Controller and MA, or Collector and MA, plus associated 409 security. 411 Collector: A function that receives a Report from a Measurement 412 Agent. 414 Configuration: A process for informing the MA about its MA-ID, 415 (optional) Group-ID and Control Channel. 417 Controller: A function that provides a Measurement Agent with its 418 Instruction. 420 Control Channel: A Channel between a Controller and a MA over which 421 Instruction Messages and Capabilities, Failure and Logging 422 Information are sent. 424 Control Protocol: The protocol delivering Instruction(s) from a 425 Controller to a Measurement Agent. It also delivers Capabilities, 426 Failure and Logging Information from the Measurement Agent to the 427 Controller. It can also be used to update the MA's Configuration. 428 It runs over the Control Channel. 430 Cycle-ID: A tag that is sent by the Controller in an Instruction and 431 echoed by the MA in its Report. The same Cycle-ID is used by several 432 MAs that use the same Measurement Method for a Metric with the same 433 Input Parameters. Hence the Cycle-ID allows the Collector to easily 434 identify Measurement Results that should be comparable. 436 Data Model: The implementation of an Information Model in a 437 particular data modelling language [RFC3444]. 439 Environmental Constraint: A parameter that is measured as part of the 440 Measurement Task, its value determining whether the rest of the 441 Measurement Task proceeds. 443 Failure Information: Information about the MA's failure to action or 444 execute an Instruction, whether concerning Measurement Tasks or 445 Reporting. 447 Group-ID: An identifier of a group of MAs. 449 Information Model: The protocol-neutral definition of the semantics 450 of the Instructions, the Report, the status of the different elements 451 of the Measurement System as well of the events in the system 452 [RFC3444]. 454 Input Parameter: A parameter whose value is left open by the Metric 455 and its Measurement Method and is set to a specific value in a 456 Measurement Task. Altering the value of an Input Parameter does not 457 change the fundamental nature of the Measurement Task. 459 Instruction: The description of Measurement Tasks for a MA to perform 460 and the details of the Report for it to send. It is the collective 461 description of the Measurement Task configurations, the configuration 462 of the Measurement Schedules, the configuration of the Report 463 Channel(s), the configuration of Report Schedule(s), and the details 464 of any suppression. 466 Instruction Message: The message that carries an Instruction from a 467 Controller to a Measurement Agent. 469 Logging Information: Information about the operation of the 470 Measurement Agent and which may be useful for debugging. 472 Measurement Agent (MA): The function that receives Instruction 473 Messages from a Controller and operates the Instruction by executing 474 Measurement Tasks (using protocols outside the initial LMAP work 475 scope and perhaps in concert with one or more other Measurement 476 Agents or Measurement Peers) and (if part of the Instruction) by 477 reporting Measurement Results to a Collector or Collectors. 479 Measurement Agent Identifier (MA-ID): a UUID [RFC4122] that 480 identifies a particular MA and is configured as part of the 481 Bootstrapping process. 483 Measurement Method: The process for assessing the value of a Metric; 484 the process of measuring some performance or reliability parameter 485 associated with the transfer of traffic. 487 Measurement Peer (MP): The function that assists a Measurement Agent 488 with Measurement Tasks and does not have an interface to the 489 Controller or Collector. 491 Measurement Result: The output of a single Measurement Task (the 492 value obtained for the parameter of interest or Metric). 494 Measurement Schedule: The schedule for performing Measurement Tasks. 496 Measurement System: The set of LMAP-defined and related components 497 that are operated by a single organisation, for the purpose of 498 measuring performance aspects of the network. 500 Measurement Task: The action performed by a particular Measurement 501 Agent that consists of the single assessment of a Metric through 502 operation of a Measurement Method role at a particular time, with all 503 of the role's Input Parameters set to specific values. 505 Measurement Traffic: the packet(s) generated by some types of 506 Measurement Method that involve measuring some parameter associated 507 with the transfer of the packet(s). 509 Metric: The quantity related to the performance and reliability of 510 the network that we'd like to know the value of. 512 Observed Traffic Flow: In RFC 7011, a Traffic Flow (or Flow) is 513 defined as a set of packets or frames passing an Observation Point in 514 the network during a certain time interval. All packets belonging to 515 a particular Flow have a set of common properties, such as packet 516 header fields, characteristics, and treatments. A Flow measured by 517 the LMAP system is termed an Observed Traffic Flow. Its properties 518 are summarized and tabulated in Measurement Results (as opposed to 519 raw capture and export). 521 Report: The set of Measurement Results and other associated 522 information (as defined by the Instruction). The Report is sent by a 523 Measurement Agent to a Collector. 525 Report Channel: A Channel between a Collector and a MA over which 526 Report messages are sent. 528 Report Protocol: The protocol delivering Report(s) from a Measurement 529 Agent to a Collector. It runs over the Report Channel. 531 Report Schedule: the schedule for sending Reports to a Collector. 533 Subscriber: An entity (associated with one or more users) that is 534 engaged in a subscription with a service provider. 536 Suppression: the temporary cessation of Measurement Tasks. 538 4. Constraints 540 The LMAP framework makes some important assumptions, which constrain 541 the scope of the initial LMAP work. 543 4.1. The measurement system is under the direction of a single 544 organisation 546 In the LMAP framework, the Measurement System is under the direction 547 of a single organisation that is responsible for any impact that its 548 measurements have on a user's quality of experience and privacy. 549 Clear responsibility is critical given that a misbehaving large-scale 550 Measurement System could potentially harm user experience, user 551 privacy and network security. 553 However, the components of an LMAP Measurement System can be deployed 554 in administrative domains that are not owned by the measuring 555 organisation. Thus, the system of functions deployed by a single 556 organisation constitutes a single LMAP domain which may span 557 ownership or other administrative boundaries. 559 4.2. Each MA may only have a single Controller at any point in time 561 A MA is instructed by one Controller and is in one Measurement 562 System. The constraint avoids different Controllers giving a MA 563 conflicting instructions and so means that the MA does not have to 564 manage contention between multiple Measurement (or Report) Schedules. 565 This simplifies the design of MAs (critical for a large-scale 566 infrastructure) and allows a Measurement Schedule to be tested on 567 specific types of MA before deployment to ensure that the end user 568 experience is not impacted (due to CPU, memory or broadband-product 569 constraints). However, a Measurement System may have several 570 Controllers. 572 5. Protocol Model 574 A protocol model [RFC4101] presents an architectural model for how 575 the protocol operates and needs to answer three basic questions: 577 1. What problem is the protocol trying to achieve? 579 2. What messages are being transmitted and what do they mean? 581 3. What are the important, but unobvious, features of the protocol? 583 An LMAP system goes through the following phases: 585 o a Bootstrapping process before the MA can take part in the other 586 three phases. 588 o a Control Protocol, which delivers Instruction Messages from a 589 Controller to a MA (amongst other things). 591 o the actual Measurement Tasks, which measure some performance or 592 reliability parameter(s) associated with the transfer of packets. 594 o a Report Protocol, which delivers Reports containing the 595 Measurement Results from a MA to a Collector. 597 The diagrams show the various LMAP messages and uses the following 598 convention: 600 o (optional): indicated by round brackets 602 o [potentially repeated]: indicated by square brackets 604 The protocol model is closely related to the Information Model 605 [I-D.ietf-lmap-information-model], which is the abstract definition 606 of the information carried by the protocol. (If there is any 607 difference between this document and the Information Model, the 608 latter is definitive, since it is on the standards track.) The 609 purpose of both is to provide a protocol and device independent view, 610 which can be implemented via specific protocols. LMAP defines a 611 specific Control Protocol and Report Protocol, but others could be 612 defined by other standards bodies or be proprietary. However it is 613 important that they all implement the same Information Model and 614 protocol model, in order to ease the definition, operation and 615 interoperability of large-scale Measurement Systems. 617 5.1. Bootstrapping process 619 The primary purpose of bootstrapping is to enable a MA to be 620 integrated into a Measurement System. The MA retrieves information 621 about itself (like its identity in the Measurement System) and about 622 the Controller, the Controller learns information about the MA, and 623 they learn about security information to communicate (such as 624 certificates and credentials). 626 Whilst this memo considers the bootstrapping process, it is beyond 627 the scope of initial LMAP work to define a bootstrap mechanism, as it 628 depends on the type of device and access. 630 As a result of the bootstrapping process the MA learns information 631 with the following aims ([I-D.ietf-lmap-information-model] defines 632 the consequent list of information elements): 634 o its identifier, either its MA-ID or a device identifier such as 635 one of its MAC or both. 637 o (optionally) a Group-ID. A Group-ID would be shared by several 638 MAs and could be useful for privacy reasons. For instance, 639 reporting the Group-ID and not the MA-ID could hinder tracking of 640 a mobile device 642 o the Control Channel, which is defined by: 644 * the address which identifies the Control Channel, such as the 645 Controller's FQDN (Fully Qualified Domain Name) [RFC1035]) 647 * security information (for example to enable the MA to decrypt 648 the Instruction Message and encrypt messages sent to the 649 Controller) 651 The details of the bootstrapping process are device /access specific. 652 For example, the information could be in the firmware, manually 653 configured or transferred via a protocol like TR-069 [TR-069]. There 654 may be a multi-stage process where the MA contacts a 'hard-coded' 655 address, which replies with the bootstrapping information. 657 The MA must learn its MA-ID before getting an Instruction, either 658 during Bootstrapping or via Configuration (Section 5.2.1). 660 5.2. Control Protocol 662 The primary purpose of the Control Protocol is to allow the 663 Controller to configure a Measurement Agent with an Instruction about 664 what Measurement Tasks to do, when to do them, and how to report the 665 Measurement Results (Section 5.2.2). The Measurement Agent then acts 666 on the Instruction autonomously. The Control Protocol also enables 667 the MA to inform the Controller about its Capabilities and any 668 Failure and Logging Information (Section 5.2.2). Finally, the 669 Control Protocol allows the Controller to update the MA's 670 Configuration. 672 5.2.1. Configuration 674 Configuration allows the Controller to update the MA about some or 675 all of the information that it obtained during the bootstrapping 676 process: the MA-ID, the (optional) Group-ID and the Control Channel. 677 The Measurement System might use Configuration for several reasons. 678 For example, the bootstrapping process could 'hard code' the MA with 679 details of an initial Controller, and then the initial Controller 680 could configure the MA with details about the Controller that sends 681 Instruction Messages. (Note that a MA only has one Control Channel, 682 and so is associated with only one Controller, at any moment.) 684 Note that an implementation may choose to combine Configuration 685 information and an Instruction Message into a single message. 687 +-----------------+ +-------------+ 688 | | | Measurement | 689 | Controller |===================================| Agent | 690 +-----------------+ +-------------+ 692 Configuration information: -> 693 (MA-ID), 694 (Group-ID), 695 (Control Channel) 696 <- Response(details) 698 5.2.2. Instruction 700 The Instruction is the description of the Measurement Tasks for a 701 Measurement Agent to do and the details of the Measurement Reports 702 for it to send. In order to update the Instruction the Controller 703 uses the Control Protocol to send an Instruction Message over the 704 Control Channel. 706 +-----------------+ +-------------+ 707 | | | Measurement | 708 | Controller |===================================| Agent | 709 +-----------------+ +-------------+ 711 Instruction: -> 712 [(Measurement Task configuration 713 URI of Metric( 714 [Input Parameter], 715 (Role) 716 (interface), 717 (Cycle-ID) 718 (measurement point)), 719 (Report Channel), 720 (Schedule), 721 (Suppression information)] 722 <- Response(details) 724 The Instruction defines information with the following aims 725 ([I-D.ietf-lmap-information-model] defines the consequent list of 726 information elements): 728 o the Measurement Task configurations, each of which needs: 730 * the Metric, specified as a URI to a registry entry; it includes 731 the specification of a Measurement Method. The registry could 732 be defined by the IETF [I-D.ietf-ippm-metric-registry], locally 733 by the operator of the Measurement System or perhaps by another 734 standards organisation. 736 * the Measurement Method role. For some Measurement Methods, 737 different parties play different roles; for example (figure A3 738 in the Appendix) an iperf sender and receiver. Each Metric and 739 its associated Measurement Method will describe all measurement 740 roles involved in the process. 742 * a boolean flag (suppress or do-not-suppress) indicating if such 743 a Measurement Task is impacted by a Suppression message (see 744 Section 5.2.2.1). Thus, the flag is an Input Parameter. 746 * any Input Parameters that need to be set for the Metric and the 747 Measurement Method. For example, the address of a Measurement 748 Peer (or other Measurement Agent) that may be involved in a 749 Measurement Task , or traffic filters associated with the 750 Observed Traffic Flow. 752 * if the device with the MA has multiple interfaces, then the 753 interface to use (if not defined, then the default interface is 754 used). 756 * optionally, a Cycle-ID. 758 * optionally, the measurement point designation 759 [I-D.ietf-ippm-lmap-path] of the MA and, if applicable, of the 760 MP or other MA. This can be useful for reporting. 762 o configuration of the Schedules, each of which needs: 764 * the timing of when the Measurement Tasks are to be performed, 765 or the Measurement Reports are to be sent. Possible types of 766 timing are periodic, calendar-based periodic, one-off immediate 767 and one-off at a future time 769 o configuration of the Report Channel(s), each of which needs: 771 * the address of the Collector, for instance its URL 773 * security for this Report Channel, for example the X.509 774 certificate 776 o Suppression information, if any (see Section 5.2.1.1) 778 A single Instruction Message may contain some or all of the above 779 parts. The finest level of granularity possible in an Instruction 780 Message is determined by the implementation and operation of the 781 Control Protocol. For example, a single Instruction Message may add 782 or update an individual Measurement Schedule - or it may only update 783 the complete set of Measurement Schedules; a single Instruction 784 Message may update both Measurement Schedules and Measurement Task 785 configurations - or only one at a time; and so on. However, 786 Suppression information always replaces (rather than adds to) any 787 previous Suppression information. 789 The MA informs the Controller that it has successfully understood the 790 Instruction Message, or that it cannot action the Instruction - for 791 example, if it doesn't include a parameter that is mandatory for the 792 requested Metric and Measurement Method, or it is missing details of 793 the target Collector. 795 The Instruction Message instructs the MA; the Control Protocol does 796 not allow the MA to negotiate, as this would add complexity to the 797 MA, Controller and Control Protocol for little benefit. 799 5.2.2.1. Suppression 801 The Instruction may include Suppression information. The main 802 motivation for Suppression is to enable the Measurement System to 803 eliminate Measurement Traffic, because there is some unexpected 804 network issue for example. There may be other circumstances when 805 Suppression is useful, for example to eliminate inessential Reporting 806 traffic (even if there is no Measurement Traffic). 808 The Suppression information may include any of the following optional 809 fields: 811 o a set of Measurement Tasks to suppress; the others are not 812 suppressed. For example, this could be useful if a particular 813 Measurement Task is overloading a Measurement Peer with 814 Measurement Traffic. 816 o a set of Measurement Schedules to suppress; the others are not 817 suppressed. For example, suppose the Measurement System has 818 defined two Schedules, one with the most critical Measurement 819 Tasks and the other with less critical ones that create a lot of 820 Measurement Traffic, then it may only want to suppress the second. 822 o a set of Reporting Schedules to suppress; the others are not 823 suppressed. This can be particularly useful in the case of a 824 Measurement Method that doesn't generate Measurement Traffic; it 825 may need to continue observing traffic flows but temporarily 826 suppress Reports due to the network footprint of the Reports. 828 o if all the previous fields are included then the MA suppresses the 829 union - in other words, it suppresses the set of Measurement 830 Tasks, the set of Measurement Schedules, and the set of Reporting 831 Schedules. 833 o if the Suppression information includes neither a set of 834 Measurement Tasks nor a set of Measurement Schedules, then the MA 835 does not begin new Measurement Tasks that have the boolean flag 836 set to "suppress"; however, the MA does begin new Measurement 837 Tasks that have the flag set to "do-not-suppress". 839 o a start time, at which suppression begins. If absent, then 840 Suppression begins immediately. 842 o an end time, at which suppression ends. If absent, then 843 Suppression continues until the MA receives an un-Suppress 844 message. 846 o a demand that the MA immediately ends on-going Measurement Task(s) 847 that are tagged for suppression. (Most likely it is appropriate 848 to delete the associated partial Measurement Result(s).) This 849 could be useful in the case of a network emergency so that the 850 operator can eliminate all inessential traffic as rapidly as 851 possible. If absent, the MA completes on-going Measurement Tasks. 853 An un-Suppress message instructs the MA no longer to suppress, 854 meaning that the MA once again begins new Measurement Tasks, 855 according to its Measurement Schedule. 857 Note that Suppression is not intended to permanently stop a 858 Measurement Task (instead, the Controller should send a new 859 Measurement Schedule), nor to permanently disable a MA (instead, some 860 kind of management action is suggested). 862 +-----------------+ +-------------+ 863 | | | Measurement | 864 | Controller |==============================| Agent | 865 +-----------------+ +-------------+ 867 Suppress: 868 [(Measurement Task), -> 869 (Measurement Schedule), 870 [start time], 871 [end time], 872 [on-going suppressed?]] 874 Un-suppress -> 876 5.2.3. Capabilities, Failure and Logging Information 878 The Control Protocol also enables the MA to inform the Controller 879 about various information, such as its Capabilities and any Failures. 880 It is also possible to use a device-specific mechanism which is 881 beyond the scope of the initial LMAP work. 883 Capabilities are information about the MA that the Controller needs 884 to know in order to correctly instruct the MA, such as: 886 o the Measurement Method (roles) that the MA supports 888 o the measurement protocol types and roles that the MA supports 890 o the interfaces that the MA has 892 o the version of the MA 894 o the version of the hardware, firmware or software of the device 895 with the MA 897 o its Instruction (this could be useful if the Controller thinks 898 something has gone wrong, and wants to check what Instruction the 899 MA is using) 901 o but not dynamic information like the currently unused CPU, memory 902 or battery life of the device with the MA. 904 Failure Information concerns why the MA has been unable to execute a 905 Measurement Task or deliver a Report, for example: 907 o the Measurement Task failed to run properly because the MA 908 (unexpectedly) has no spare CPU cycles 910 o the MA failed to record the Measurement Results because it 911 (unexpectedly) is out of spare memory 913 o a Report failed to deliver Measurement Results because the 914 Collector (unexpectedly) is not responding 916 o but not if a Measurement Task correctly doesn't start. For 917 example, the first step of some Measurement Methods is for the MA 918 to check there is no cross-traffic. 920 Logging Information concerns how the MA is operating and may help 921 debugging, for example: 923 o the last time the MA ran a Measurement Task 924 o the last time the MA sent a Measurement Report 926 o the last time the MA received an Instruction Message 928 o whether the MA is currently Suppressing Measurement Tasks 930 Capabilities, Failure and Logging Information are sent by the MA, 931 either in response to a request from the Controller (for example, if 932 the Controller forgets what the MA can do or otherwise wants to 933 resynchronize what it knows about the MA), or on its own initiative 934 (for example when the MA first communicates with a Controller or if 935 it becomes capable of a new Measurement Method). Another example of 936 the latter case is if the device with the MA re-boots, then the MA 937 should notify its Controller in case its Instruction needs to be 938 updated; to avoid a "mass calling event" after a widespread power 939 restoration affecting many MAs, it is sensible for an MA to pause for 940 a random delay, perhaps in the range of one minute or so. 942 +-----------------+ +-------------+ 943 | | | Measurement | 944 | Controller |==================================| Agent | 945 +-----------------+ +-------------+ 947 (Instruction: 948 [(Request Capabilities), 949 (Request Failure Information), 950 (Request Logging Information), 951 (Request Instruction)]) -> 952 <- (Capabilities), 953 (Failure Information), 954 (Logging Information), 955 (Instruction) 957 5.3. Operation of Measurement Tasks 959 This LMAP framework is neutral to what the actual Measurement Task 960 is. It does not define Metrics and Measurement Methods, these are 961 defined elsewhere. 963 The MA carries out the Measurement Tasks as instructed, unless it 964 gets an updated Instruction. The MA acts autonomously, in terms of 965 operation of the Measurement Tasks and reporting of the Results; it 966 doesn't do a 'safety check' with the Controller to ask whether it 967 should still continue with the requested Measurement Tasks. 969 The MA may operate Measurement Tasks sequentially or in parallel (see 970 Section 5.3.2). 972 5.3.1. Starting and Stopping Measurement Tasks 974 This LMAP framework does not define a generic start and stop process, 975 since the correct approach depends on the particular Measurement 976 Task; the details are defined as part of each Measurement Method. 977 This section provides some general hints. The MA does not inform the 978 Controller about Measurement Tasks starting and stopping. 980 Before beginning a Measurement Task the MA may want to run a pre- 981 check. (The pre-check could be defined as a separate, preceding Task 982 or as the first part of a larger Task.) 984 For Measurement Tasks that observe existing traffic, action could 985 include: 987 o checking that there is traffic of interest; 989 o checking that the device with the MA has enough resources to 990 execute the Measurement Task reliably. Note that the designer of 991 the Measurement System should ensure that the device's 992 capabilities are normally sufficient to comfortably operate the 993 Measurement Tasks. 995 For Measurement Tasks that generate Measurement Traffic, a pre-check 996 could include: 998 o the MA checking that there is no cross-traffic. In other words, a 999 check that the end-user isn't already sending traffic; 1001 o the MA checking with the Measurement Peer (or other Measurement 1002 Agent) involved in the Measurement Task that it can handle a new 1003 Measurement Task. For example, the Measurement Peer may already 1004 be handling many Measurement Tasks with other MAs; 1006 o sending traffic that probes the path to check it isn't overloaded; 1008 o checking that the device with the MA has enough resources to 1009 execute the Measurement Task reliably. 1011 It is possible that similar checks continue during the Measurement 1012 Task, especially one that is long-running and/or creates a lot of 1013 Measurement Traffic, and might lead to it being abandoned whilst in- 1014 progress. A Measurement Task could also be abandoned in response to 1015 a "suppress" message (see Section 5.2.1). Action could include: 1017 o For 'upload' tests, the MA not sending traffic 1018 o For 'download' tests, the MA closing the TCP connection or sending 1019 a TWAMP (Two-Way Active Measurement Protocol) Stop control message 1020 [RFC5357]. 1022 The Controller may want a MA to run the same Measurement Task 1023 indefinitely (for example, "run the 'upload speed' Measurement Task 1024 once an hour until further notice"). To avoid the MA generating 1025 traffic forever after a Controller has permanently failed (or 1026 communications with the Controller have failed), the MA can be 1027 configured with a time limit; if the MA doesn't hear from the 1028 Controller for this length of time, then it stops operating 1029 Measurement Tasks. 1031 5.3.2. Overlapping Measurement Tasks 1033 It is possible that a MA starts a new Measurement Task before another 1034 Measurement Task has completed. This may be intentional (the way 1035 that the Measurement System has designed the Measurement Schedules), 1036 but it could also be unintentional - for instance, if a Measurement 1037 Task has a 'wait for X' step which pauses for an unexpectedly long 1038 time. This document makes no assumptions about the impact of one 1039 Measurement Task on another. 1041 The operator of the Measurement System can handle (or not) 1042 overlapping Measurement Tasks in any way they choose - it is a policy 1043 or implementation issue and not the concern of LMAP. Some possible 1044 approaches are: to configure the MA not to begin the second 1045 Measurement Task; to start the second Measurement Task as usual; for 1046 the action to be an Input Parameter of the Measurement Task; and so 1047 on. 1049 It may be important to include in the Measurement Report the fact 1050 that the Measurement Task overlapped with another. 1052 5.4. Report Protocol 1054 The primary purpose of the Report Protocol is to allow a Measurement 1055 Agent to report its Measurement Results to a Collector, along with 1056 the context in which they were obtained. 1058 +-----------------+ +-------------+ 1059 | | | Measurement | 1060 | Collector |==================================| Agent | 1061 +-----------------+ +-------------+ 1063 <- Report: 1064 [MA-ID &/or Group-ID], 1065 [Measurement Result], 1066 [details of Measurement Task], 1067 [Cycle-ID] 1068 ACK -> 1070 The Report contains: 1072 o the MA-ID or a Group-ID (to anonymise results) 1074 o the actual Measurement Results, including the time they were 1075 measured. In general the time is simply the MA's best estimate 1076 and there is no guarantee on the accuracy or granularity of the 1077 information. It is possible that some specific analysis of a 1078 particular Measurement Method's Results will impose timing 1079 requirements. 1081 o the details of the Measurement Task (to avoid the Collector having 1082 to ask the Controller for this information later). For example, 1083 the interface used for the measurements. 1085 o the Cycle-ID, if one was included in the Instruction. 1087 o perhaps the Subscriber's service parameters (see Section 5.4.1). 1089 o the measurement point designation of the MA and, if applicable, 1090 the MP or other MA, if the information was included in the 1091 Instruction. This numbering system is defined in 1092 [I-D.ietf-ippm-lmap-path] and allows a Measurement Report to 1093 describe abstractly the path measured (for example, "from a MA at 1094 a home gateway to a MA at a DSLAM"). Also, the MA can anonymise 1095 results by including measurement point designations instead of IP 1096 addresses (Section 8.6.2). 1098 The MA sends Reports as defined by the Instruction. It is possible 1099 that the Instruction tells the MA to report the same Results to more 1100 than one Collector, or to report a different subset of Results to 1101 different Collectors. It is also possible that a Measurement Task 1102 may create two (or more) Measurement Results, which could be reported 1103 differently (for example, one Result could be reported periodically, 1104 whilst the second Result could be an alarm that is created as soon as 1105 the measured value of the Metric crosses a threshold and that is 1106 reported immediately). 1108 Optionally, a Report is not sent when there are no Measurement 1109 Results. 1111 In the initial LMAP Information Model and Report Protocol, for 1112 simplicity we assume that all Measurement Results are reported as-is, 1113 but allow extensibility so that a Measurement System (or perhaps a 1114 second phase of LMAP) could allow a MA to: 1116 o label, or perhaps not include, Measurement Results impacted by, 1117 for instance, cross-traffic or a Measurement Peer (or other 1118 Measurement Agent) being busy 1120 o label Measurement Results obtained by a Measurement Task that 1121 overlapped with another 1123 o not report the Measurement Results if the MA believes that they 1124 are invalid 1126 o detail when Suppression started and ended 1128 As discussed in Section 6.1, data analysis of the results should 1129 carefully consider potential bias from any Measurement Results that 1130 are not reported, or from Measurement Results that are reported but 1131 may be invalid. 1133 5.4.1. Reporting of Subscriber's service parameters 1135 The Subscriber's service parameters are information about his/her 1136 broadband contract, line rate and so on. Such information is likely 1137 to be needed to help analyse the Measurement Results, for example to 1138 help decide whether the measured download speed is reasonable. 1140 The information could be transferred directly from the Subscriber 1141 parameter database to the data analysis tools. If the subscriber's 1142 service parameters are available to the MAs, they could be reported 1143 with the Measurement Results in the Report Protocol. How (and if) 1144 the MA knows such information is likely to depend on the device type. 1145 The MA could either include the information in a Measurement Report 1146 or separately. 1148 5.5. Operation of LMAP over the underlying packet transfer mechanism 1150 The above sections have described LMAP's protocol model. Other 1151 specifications will define the actual Control and Report Protocols, 1152 possibly operating over an existing protocol, such as REST-style 1153 HTTP(S). It is also possible that a different choice is made for the 1154 Control and Report Protocols, for example NETCONF-YANG [RFC6241] and 1155 IPFIX (Internet Protocol Flow Information Export) [RFC7011] 1156 respectively. 1158 From an LMAP perspective, the Controller needs to know that the MA 1159 has received the Instruction Message, or at least that it needs to be 1160 re-sent as it may have failed to be delivered. Similarly the MA 1161 needs to know about the delivery of Capabilities and Failure 1162 information to the Controller and Reports to the Collector. How this 1163 is done depends on the design of the Control and Report Protocols and 1164 the underlying packet transfer mechanism. 1166 For the Control Protocol, the underlying packet transfer mechanism 1167 could be: 1169 o a 'push' protocol (that is, from the Controller to the MA) 1171 o a multicast protocol (from the Controller to a group of MAs) 1173 o a 'pull' protocol. The MA periodically checks with Controller if 1174 the Instruction has changed and pulls a new Instruction if 1175 necessary. A pull protocol seems attractive for a MA behind a NAT 1176 or firewall (as is typical for a MA on an end-user's device), so 1177 that it can initiate the communications. It also seems attractive 1178 for a MA on a mobile device, where the Controller might not know 1179 how to reach the MA. A pull mechanism is likely to require the MA 1180 to be configured with how frequently it should check in with the 1181 Controller, and perhaps what it should do if the Controller is 1182 unreachable after a certain number of attempts. 1184 o a hybrid protocol. In addition to a pull protocol, the Controller 1185 can also push an alert to the MA that it should immediately pull a 1186 new Instruction. 1188 For the Report Protocol, the underlying packet transfer mechanism 1189 could be: 1191 o a 'push' protocol (that is, from the MA to the Collector) 1193 o perhaps supplemented by the ability for the Collector to 'pull' 1194 Measurement Results from a MA. 1196 5.6. Items beyond the scope of the initial LMAP work 1198 There are several potential interactions between LMAP elements that 1199 are beyond the scope of the initial LMAP work: 1201 1. It does not define a coordination process between MAs. Whilst a 1202 Measurement System may define coordinated Measurement Schedules 1203 across its various MAs, there is no direct coordination between 1204 MAs. 1206 2. It does not define interactions between the Collector and 1207 Controller. It is quite likely that there will be such 1208 interactions, optionally intermediated by the data analysis 1209 tools. For example, if there is an "interesting" Measurement 1210 Result then the Measurement System may want to trigger extra 1211 Measurement Tasks that explore the potential cause in more 1212 detail; or if the Collector unexpectedly does not hear from a MA, 1213 then the Measurement System may want to trigger the Controller to 1214 send a fresh Instruction Message to the MA. 1216 3. It does not define coordination between different Measurement 1217 Systems. For example, it does not define the interaction of a MA 1218 in one Measurement System with a Controller or Collector in a 1219 different Measurement System. Whilst it is likely that the 1220 Control and Report Protocols could be re-used or adapted for this 1221 scenario, any form of coordination between different 1222 organisations involves difficult commercial and technical issues 1223 and so, given the novelty of large-scale measurement efforts, any 1224 form of inter-organisation coordination is outside the scope of 1225 the initial LMAP work. Note that a single MA is instructed by a 1226 single Controller and is only in one Measurement System. 1228 * An interesting scenario is where a home contains two 1229 independent MAs, for example one controlled by a regulator and 1230 one controlled by an ISP. Then the Measurement Traffic of one 1231 MA is treated by the other MA just like any other end-user 1232 traffic. 1234 4. It does not consider how to prevent a malicious party "gaming the 1235 system". For example, where a regulator is running a Measurement 1236 System in order to benchmark operators, a malicious operator 1237 could try to identify the broadband lines that the regulator was 1238 measuring and prioritise that traffic. It is assumed this is a 1239 policy issue and would be dealt with through a code of conduct 1240 for instance. 1242 5. It does not define how to analyse Measurement Results, including 1243 how to interpret missing Results. 1245 6. It does not specifically define a end-user-controlled Measurement 1246 System, see sub-section 5.6.1. 1248 5.6.1. End-user-controlled measurement system 1250 This framework concentrates on the cases where an ISP or a regulator 1251 runs the Measurement System. However, we expect that LMAP 1252 functionality will also be used in the context of an end-user- 1253 controlled Measurement System. There are at least two ways this 1254 could happen (they have various pros and cons): 1256 1. an end-user could somehow request the ISP- (or regulator-) run 1257 Measurement System to test his/her line. The ISP (or regulator) 1258 Controller would then send an Instruction to the MA in the usual 1259 LMAP way. 1261 2. an end-user could deploy their own Measurement System, with their 1262 own MA, Controller and Collector. For example, the user could 1263 implement all three functions onto the same end-user-owned end 1264 device, perhaps by downloading the functions from the ISP or 1265 regulator. Then the LMAP Control and Report Protocols do not 1266 need to be used, but using LMAP's Information Model would still 1267 be beneficial. A Measurement Peer (or other MA involved in a 1268 Measurement Task) could be in the home gateway or outside the 1269 home network; in the latter case the Measurement Peer is highly 1270 likely to be run by a different organisation, which raises extra 1271 privacy considerations. 1273 In both cases there will be some way for the end-user to initiate the 1274 Measurement Task(s). The mechanism is outside the scope of the 1275 initial LMAP work, but could include the user clicking a button on a 1276 GUI or sending a text message. Presumably the user will also be able 1277 to see the Measurement Results, perhaps summarised on a webpage. It 1278 is suggested that these interfaces conform to the LMAP guidance on 1279 privacy in Section 8. 1281 6. Deployment considerations 1283 6.1. Controller and the measurement system 1285 The Controller should understand both the MA's LMAP Capabilities (for 1286 instance what Metrics and Measurement Methods it can perform) and 1287 about the MA's other capabilities like processing power and memory. 1288 This allows the Controller to make sure that the Measurement Schedule 1289 of Measurement Tasks and the Reporting Schedule are sensible for each 1290 MA that it instructs. 1292 An Instruction is likely to include several Measurement Tasks. 1293 Typically these run at different times, but it is also possible for 1294 them to run at the same time. Some Tasks may be compatible, in that 1295 they do not affect each other's Results, whilst with others great 1296 care would need to be taken. Some Tasks may be complementary. For 1297 example, one Task may be followed by a traceroute Task to the same 1298 destination address, in order to learn the network path that was 1299 measured. 1301 The Controller should ensure that the Measurement Tasks do not have 1302 an adverse effect on the end user. Tasks, especially those that 1303 generate a substantial amount of Measurement Traffic, will often 1304 include a pre-check that the user isn't already sending traffic 1305 (Section 5.3). Another consideration is whether Measurement Traffic 1306 will impact a Subscriber's bill or traffic cap. 1308 A Measurement System may have multiple Controllers (but note the 1309 overriding principle that a single MA is instructed by a single 1310 Controller at any point in time (Section 4.2)). For example, there 1311 could be different Controllers for different types of MA (home 1312 gateways, tablets) or locations (Ipswich, Edinburgh, Paris), for load 1313 balancing or to cope with failure of one Controller. 1315 The measurement system also needs to consider carefully how to 1316 interpret missing Results. The correct interpretation depends on why 1317 the Results are missing (perhaps related to measurement suppression 1318 or delayed Report submission), and potentially on the specifics of 1319 the Measurement Task and Measurement Schedule. For example, the set 1320 of packets represented by a Flow may be empty; that is, an Observed 1321 Traffic Flow may represent zero or more packets. The Flow would 1322 still be reported according to schedule. 1324 6.2. Measurement Agent 1326 The MA should be cautious about resuming Measurement Tasks if it re- 1327 boots or has been off-line for some time, as its Instruction may be 1328 stale. In the former case it also needs to ensure that its clock has 1329 re-set correctly, so that it interprets the Schedule correctly. 1331 If the MA runs out of storage space for Measurement Results or can't 1332 contact the Controller, then the appropriate action is specific to 1333 the device and Measurement System. 1335 The Measurement Agent could take a number of forms: a dedicated 1336 probe, software on a PC, embedded into an appliance, or even embedded 1337 into a gateway. A single site (home, branch office etc.) that is 1338 participating in a measurement could make use of one or multiple 1339 Measurement Agents or Measurement Peers in a single measurement. 1341 The Measurement Agent could be deployed in a variety of locations. 1342 Not all deployment locations are available to every kind of 1343 Measurement Agent. There are also a variety of limitations and 1344 trade-offs depending on the final placement. The next sections 1345 outline some of the locations a Measurement Agent may be deployed. 1346 This is not an exhaustive list and combinations may also apply. 1348 6.2.1. Measurement Agent on a networked device 1350 A MA may be embedded on a device that is directly connected to the 1351 network, such as a MA on a smartphone. Other examples include a MA 1352 downloaded and installed on a subscriber's laptop computer or tablet 1353 when the network service is provided on wired or other wireless radio 1354 technologies, such as Wi-Fi. 1356 6.2.2. Measurement Agent embedded in site gateway 1358 A Measurement Agent embedded with the site gateway, for example a 1359 home router or the edge router of a branch office in a managed 1360 service environment, is one of better places the Measurement Agent 1361 could be deployed. All site-to-ISP traffic would traverse through 1362 the gateway. So, Measurement Methods that measure user traffic could 1363 easily be performed. Similarly, due to this user traffic visibility, 1364 a Measurement Method that generates Measurement Traffic could ensure 1365 it does not compete with user traffic. Generally NAT and firewall 1366 services are built into the gateway, allowing the Measurement Agent 1367 the option to offer its Controller-facing management interface 1368 outside of the NAT/firewall. This placement of the management 1369 interface allows the Controller to unilaterally contact the 1370 Measurement Agent for instructions. However, a Measurement Agent on 1371 a site gateway (whether end-user service-provider owned) will 1372 generally not be directly available for over the top providers, the 1373 regulator, end users or enterprises. 1375 6.2.3. Measurement Agent embedded behind site NAT /firewall 1377 The Measurement Agent could also be embedded behind a NAT, a 1378 firewall, or both. In this case the Controller may not be able to 1379 unilaterally contact the Measurement Agent unless either static port 1380 forwarding or firewall pin holing is configured. Configuring port 1381 forwarding could use protocols such as PCP [RFC6887], TR-069 [TR-069] 1382 or UPnP [UPnP]. To open a pin hole in the firewall, the Measurement 1383 Agent could send keepalives towards the Controller (and perhaps use 1384 these also as a network reachability test). 1386 6.2.4. Multi-homed Measurement Agent 1388 If the device with the Measurement Agent is single homed then there 1389 is no confusion about what interface to measure. Similarly, if the 1390 MA is at the gateway and the gateway only has a single WAN-side and a 1391 single LAN-side interface, there is little confusion - for 1392 Measurement Methods that generate Measurement Traffic, the location 1393 of the other MA or Measurement Peer determines whether the WAN or LAN 1394 is measured. 1396 However, the device with the Measurement Agent may be multi-homed. 1397 For example, a home or campus may be connected to multiple broadband 1398 ISPs, such as a wired and wireless broadband provider, perhaps for 1399 redundancy or load- sharing. It may also be helpful to think of dual 1400 stack IPv4 and IPv6 broadband devices as multi-homed. More 1401 generally, Section 3.2 of [RFC7368] describes dual-stack and multi- 1402 homing topologies that might be encountered in a home network, 1403 [RFC6419] provides the current practices of multi-interfaces hosts, 1404 and the Multiple Interfaces (mif) working group covers cases where 1405 hosts are either directly attached to multiple networks (physical or 1406 virtual) or indirectly (multiple default routers, etc.). In these 1407 cases, there needs to be clarity on which network connectivity option 1408 is being measured. 1410 One possibility is to have a Measurement Agent per interface. Then 1411 the Controller's choice of MA determines which interface is measured. 1412 However, if a MA can measure any of the interfaces, then the 1413 Controller defines in the Instruction which interface the MA should 1414 use for a Measurement Task; if the choice of interface is not defined 1415 then the MA uses the default one. Explicit definition is preferred 1416 if the Measurement System wants to measure the performance of a 1417 particular network, whereas using the default is better if the 1418 Measurement System wants to include the impact of the MA's interface 1419 selection algorithm. In any case, the Measurement Result should 1420 include the network that was measured. 1422 6.2.5. Measurement Agent embedded in ISP network 1424 A MA may be embedded on a device that is part of an ISP's network, 1425 such as a router or switch. Usually the network devices with an 1426 embedded MA will be strategically located, such as a Carrier Grade 1427 NAT or ISP Gateway. [I-D.ietf-ippm-lmap-path] gives many examples 1428 where a MA might be located within a network to provide an 1429 intermediate measurement point on the end-to-end path. Other 1430 examples include a network device whose primary role is to host MA 1431 functions and the necessary measurement protocol. 1433 6.3. Measurement Peer 1435 A Measurement Peer participates in some Measurement Methods. It may 1436 have specific functionality to enable it to participate in a 1437 particular Measurement Method. On the other hand, other Measurement 1438 Methods may require no special functionality. For example if the 1439 Measurement Agent sends a ping to example.com then the server at 1440 example.com plays the role of a Measurement Peer; or if the MA 1441 monitors existing traffic, then the existing end points are 1442 Measurement Peers. 1444 A device may participate in some Measurement Methods as a Measurement 1445 Agent and in others as a Measurement Peer. 1447 Measurement Schedules should account for limited resources in a 1448 Measurement Peer when instructing a MA to execute measurements with a 1449 Measurement Peer. In some measurement protocols, such as [RFC4656] 1450 and [RFC5357], the Measurement Peer can reject a measurement session 1451 or refuse a control connection prior to setting-up a measurement 1452 session and so protect itself from resource exhaustion. This is a 1453 valuable capability because the MP may be used by more than one 1454 organisation. 1456 6.4. Deployment examples 1458 In this section we describe some deployment scenarios that are 1459 feasible within the LMAP framework defined in this document. 1461 A very simple example of a Measurement Peer (MP) is a web server that 1462 the MA is downloading a web page from (such as www.example.com) in 1463 order to perform a speed test. The web server is a MP and from its 1464 perspective, the MA is just another client; the MP doesn't have a 1465 specific function for assisting measurements. This is described in 1466 the figure A1. 1468 ^ 1469 +----------------+ Web Traffic +----------------+ non-LMAP 1470 |MA: Web Client |<------------>| MP: Web Server | Scope 1471 | | +----------------+ | 1472 ...|................|....................................V... 1473 | LMAP interface | ^ 1474 +----------------+ | 1475 ^ | | 1476 Instruction | | Report | 1477 | +-----------------+ | 1478 | | | 1479 | v LMAP 1480 +------------+ +------------+ Scope 1481 | Controller | | Collector | | 1482 +------------+ +------------+ V 1484 Schematic of LMAP-based Measurement System, 1485 with Web server as Measurement Peer 1487 Another case that is slightly different than this would be the one of 1488 a TWAMP-responder. This is also a MP, with a helper function, the 1489 TWAMP server, which is specially deployed to assist the MAs that 1490 perform TWAMP tests. Another example is with a ping server, as 1491 described in Section 2. 1493 A further example is the case of a traceroute like measurement. In 1494 this case, for each packet sent, the router where the TTL expires is 1495 performing the MP function. So for a given Measurement Task, there 1496 is one MA involved and several MPs, one per hop. 1498 In figure A2 we depict the case of an OWAMP (One-Way Active 1499 Measurement Protocol) responder acting as an MP. In this case, the 1500 helper function in addition reports results back to the MA. So it 1501 has both a data plane and control interface with the MA. 1503 +----------------+ OWAMP +----------------+ ^ 1504 | MA: OWAMP |<--control--->| MP: | | 1505 | control-client |-test-traffic>| OWAMP server & | non-LMAP 1506 | fetch-client & |<----fetch----| session-rec'ver| Scope 1507 | session-sender | | | | 1508 | | +----------------+ | 1509 ...|................|....................................v... 1510 | LMAP interface | ^ 1511 +----------------+ | 1512 ^ | | 1513 Instruction | | Report | 1514 | +-----------------+ | 1515 | | | 1516 | v LMAP 1517 +------------+ +------------+ Scope 1518 | Controller | | Collector | | 1519 +------------+ +------------+ v 1521 Schematic of LMAP-based Measurement System, 1522 with OWAMP server as Measurement Peer 1524 However, it is also possible to use two Measurement Agents when 1525 performing one way Measurement Tasks, as described in figure A3 1526 below. Both MAs are instructed by the Controller: MA-1 to send the 1527 traffic and MA-2 to measure the received traffic and send Reports to 1528 the Collector. Note that the Measurement Task at MA-2 can listen for 1529 traffic from MA-1 and respond multiple times without having to be 1530 rescheduled. 1532 +----------------+ +----------------+ ^ 1533 | MA-1: | | MA-2: | non-LMAP 1534 | iperf -u sender|-UDP traffic->| iperf -u recvr | Scope 1535 | | | | v 1536 ...|................|..............|................|....v... 1537 | LMAP interface | | LMAP interface | ^ 1538 +----------------+ +----------------+ | 1539 ^ ^ | | 1540 Instruction | Instruction{Report} | | Report | 1541 {task, | +-------------------+ | | 1542 schedule} | | | | 1543 | | v LMAP 1544 +------------+ +------------+ Scope 1545 | Controller | | Collector | | 1546 +------------+ +------------+ v 1548 Schematic of LMAP-based Measurement System, with two 1549 Measurement Agents cooperating to measure UDP traffic 1551 Next, we consider Measurement Methods that meter the Observed Traffic 1552 Flow. Traffic generated in one point in the network flowing towards 1553 a given destination and the traffic is observed in some point along 1554 the path. One way to implement this is that the endpoints generating 1555 and receiving the traffic are not instructed by the Controller; hence 1556 they are MPs. The MA is located along the path with a monitor 1557 function that measures the traffic. The MA is instructed by the 1558 Controller to monitor that particular traffic and to send the Report 1559 to the Collector. It is depicted in figure A4 below. 1561 +--------+ +----------------+ +--------+ ^ 1562 |End user| | MA: Monitor | Observed |End user| | 1563 | or MP |<--|----------------|--traffic-->| or MP | non-LMAP 1564 | | | | flow | | Scope 1565 +--------+ | | +--------+ | 1566 ...|................|............................v.. 1567 | LMAP interface | ^ 1568 +----------------+ | 1569 ^ | | 1570 Instruction | | Report | 1571 | +-----------------+ | 1572 | | | 1573 | v LMAP 1574 +------------+ +------------+ Scope 1575 | Controller | | Collector | | 1576 +------------+ +------------+ v 1578 Schematic of LMAP-based Measurement System, 1579 with a Measurement Agent monitoring traffic 1581 7. Security considerations 1583 The security of the LMAP framework should protect the interests of 1584 the measurement operator(s), the network user(s) and other actors who 1585 could be impacted by a compromised measurement deployment. The 1586 Measurement System must secure the various components of the system 1587 from unauthorised access or corruption. Much of the general advice 1588 contained in section 6 of [RFC4656] is applicable here. 1590 The process to upgrade the firmware in an MA is outside the scope of 1591 the initial LMAP work, similar to the protocol to bootstrap the MAs 1592 (as specified in the charter). However, systems which provide remote 1593 upgrade must secure authorised access and integrity of the process. 1595 We assume that each Measurement Agent (MA) will receive its 1596 Instructions from a single organisation, which operates the 1597 Controller. These Instructions must be authenticated (to ensure that 1598 they come from the trusted Controller), checked for integrity (to 1599 ensure no-one has tampered with them) and not vulnerable to replay 1600 attacks. If a malicious party can gain control of the MA they can 1601 use it to launch DoS attacks at targets, create a platform for 1602 pervasive monitoring [RFC7258], reduce the end user's quality of 1603 experience and corrupt the Measurement Results that are reported to 1604 the Collector. By altering the Measurement Tasks and/or the address 1605 that Results are reported to, they can also compromise the 1606 confidentiality of the network user and the MA environment (such as 1607 information about the location of devices or their traffic). The 1608 Instruction Messages also need to be encrypted to maintain 1609 confidentiality, as the information might be useful to an attacker. 1611 Reporting by the MA must be encrypted to maintain confidentiality, so 1612 that only the authorised Collector can decrypt the results, to 1613 prevent the leakage of confidential or private information. 1614 Reporting must also be authenticated (to ensure that it comes from a 1615 trusted MA and that the MA reports to a genuine Collector) and not 1616 vulnerable to tampering (which can be ensured through integrity and 1617 replay checks). It must not be possible to fool a MA into injecting 1618 falsified data and the results must also be held and processed 1619 securely after collection and analysis. See section 8.5.2 below for 1620 additional considerations on stored data compromise, and section 8.6 1621 on potential mitigations for compromise. 1623 Since Collectors will be contacted repeatedly by MAs using the 1624 Collection Protocol to convey their recent results, a successful 1625 attack to exhaust the communication resources would prevent a 1626 critical operation: reporting. Therefore, all LMAP Collectors should 1627 implement technical mechanisms to: 1629 o limit the number of reporting connections from a single MA 1630 (simultaneous, and connections per unit time). 1632 o limit the transmission rate from a single MA. 1634 o limit the memory/storage consumed by a single MA's reports. 1636 o efficiently reject reporting connections from unknown sources. 1638 o separate resources if multiple authentication strengths are used, 1639 where the resources should be separated according to each class of 1640 strength. 1642 A corrupted MA could report falsified information to the Collector. 1643 Whether this can be effectively mitigated depends on the platform on 1644 which the MA is deployed, but where the MA is deployed on a customer- 1645 controlled device then the reported data is to some degree inherently 1646 untrustworthy. Further, a sophisticated party could distort some 1647 Measurement Methods, perhaps by dropping or delaying packets for 1648 example. This suggests that the network operator should be cautious 1649 about relying on Measurement Results for action such as refunding 1650 fees if a service level agreement is not met. 1652 As part of the protocol design, it will be decided how LMAP operates 1653 over the underlying protocol (Section 5.5). The choice raises 1654 various security issues, such as how to operate through a NAT and how 1655 to protect the Controller and Collector from denial of service 1656 attacks. 1658 The security mechanisms described above may not be strictly necessary 1659 if the network's design ensures the LMAP components and their 1660 communications are already secured, for example potentially if they 1661 are all part of an ISP's dedicated management network. 1663 Finally, there are three other issues related to security: privacy 1664 (considered in Section 8 below), availability and 'gaming the 1665 system'. While the loss of some MAs may not be considered critical, 1666 the unavailability of the Collector could mean that valuable business 1667 data or data critical to a regulatory process is lost. Similarly, 1668 the unavailability of a Controller could mean that the MAs do not 1669 operate a correct Measurement Schedule. 1671 A malicious party could "game the system". For example, where a 1672 regulator is running a Measurement System in order to benchmark 1673 operators, an operator could try to identify the broadband lines that 1674 the regulator was measuring and prioritise that traffic. Normally, 1675 this potential issue is handled by a code of conduct. It is outside 1676 the scope of the initial LMAP work to consider the issue. 1678 8. Privacy considerations 1680 The LMAP work considers privacy as a core requirement and will ensure 1681 that by default the Control and Report Protocols operate in a 1682 privacy-sensitive manner and that privacy features are well-defined. 1684 This section provides a set of privacy considerations for LMAP. This 1685 section benefits greatly from the timely publication of [RFC6973]. 1686 Privacy and security (Section 7) are related. In some jurisdictions 1687 privacy is called data protection. 1689 We begin with a set of assumptions related to protecting the 1690 sensitive information of individuals and organisations participating 1691 in LMAP-orchestrated measurement and data collection. 1693 8.1. Categories of entities with information of interest 1695 LMAP protocols need to protect the sensitive information of the 1696 following entities, including individuals and organisations who 1697 participate in measurement and collection of results. 1699 o Individual Internet users: Persons who utilise Internet access 1700 services for communications tasks, according to the terms of 1701 service of a service agreement. Such persons may be a service 1702 Subscriber, or have been given permission by the Subscriber to use 1703 the service. 1705 o Internet service providers: Organisations who offer Internet 1706 access service subscriptions, and thus have access to sensitive 1707 information of individuals who choose to use the service. These 1708 organisations desire to protect their Subscribers and their own 1709 sensitive information which may be stored in the process of 1710 performing Measurement Tasks and collecting Results. 1712 o Regulators: Public authorities responsible for exercising 1713 supervision of the electronic communications sector, and which may 1714 have access to sensitive information of individuals who 1715 participate in a measurement campaign. Similarly, regulators 1716 desire to protect the participants and their own sensitive 1717 information. 1719 o Other LMAP system operators: Organisations who operate Measurement 1720 Systems or participate in measurements in some way. 1722 Although privacy is a protection extended to individuals, we include 1723 discussion of ISPs and other LMAP system operators in this section. 1724 These organisations have sensitive information involved in the LMAP 1725 system, and many of the same dangers and mitigations are applicable. 1726 Further, the ISPs store information on their Subscribers beyond that 1727 used in the LMAP system (for instance billing information), and there 1728 should be a benefit in considering all the needs and potential 1729 solutions coherently. 1731 8.2. Examples of sensitive information 1733 This section gives examples of sensitive information which may be 1734 measured or stored in a Measurement System, and which is to be kept 1735 private by default in the LMAP core protocols. 1737 Examples of Subscriber or authorised Internet user sensitive 1738 information: 1740 o Sub-IP layer addresses and names (MAC address, base station ID, 1741 SSID) 1743 o IP address in use 1745 o Personal Identification (real name) 1747 o Location (street address, city) 1749 o Subscribed service parameters 1750 o Contents of traffic (activity, DNS queries, destinations, 1751 equipment types, account info for other services, etc.) 1753 o Status as a study volunteer and Schedule of Measurement Tasks 1755 Examples of Internet Service Provider sensitive information: 1757 o Measurement device identification (equipment ID and IP address) 1759 o Measurement Instructions (choice of measurements) 1761 o Measurement Results (some may be shared, others may be private) 1763 o Measurement Schedule (exact times) 1765 o Network topology (locations, connectivity, redundancy) 1767 o Subscriber billing information, and any of the above Subscriber 1768 information known to the provider. 1770 o Authentication credentials (such as certificates) 1772 Other organisations will have some combination of the lists above. 1773 The LMAP system would not typically expose all of the information 1774 above, but could expose a combination of items which could be 1775 correlated with other pieces collected by an attacker (as discussed 1776 in the section on Threats below). 1778 8.3. Different privacy issues raised by different sorts of Measurement 1779 Methods 1781 Measurement Methods raise different privacy issues depending on 1782 whether they measure traffic created specifically for that purpose, 1783 or whether they measure user traffic. 1785 Measurement Tasks conducted on user traffic store sensitive 1786 information, however briefly this storage may be. We note that some 1787 authorities make a distinction on time of storage, and information 1788 that is kept only temporarily to perform a communications function is 1789 not subject to regulation (for example, active queue management, deep 1790 packet inspection). Such Measurement Tasks could reveal all the 1791 websites a Subscriber visits and the applications and/or services 1792 they use. This issue is not specific to LMAP. For instance, IPFIX 1793 has addressed similar issues (see section 11.8 of [RFC7011]). 1795 Other types of Measurement Task are conducted on traffic which is 1796 created specifically for the purpose. Even if a user host generates 1797 Measurement Traffic, there is limited sensitive information about the 1798 Subscriber present and stored in the Measurement System: 1800 o IP address in use (and possibly sub-IP addresses and names) 1802 o Status as a study volunteer and Schedule of Measurement Tasks 1804 On the other hand, for a service provider the sensitive information 1805 like Measurement Results is the same for all Measurement Tasks. 1807 From the Subscriber perspective, both types of Measurement Task 1808 potentially expose the description of Internet access service and 1809 specific service parameters, such as subscribed rate and type of 1810 access. 1812 8.4. Privacy analysis of the communication models 1814 This section examines each of the protocol exchanges described at a 1815 high level in Section 5 and some example Measurement Tasks, and 1816 identifies specific sensitive information which must be secured 1817 during communication for each case. With the protocol-related 1818 sensitive information identified, we can better consider the threats 1819 described in the following section. 1821 From the privacy perspective, all entities participating in LMAP 1822 protocols can be considered "observers" according to the definition 1823 in [RFC6973]. Their stored information potentially poses a threat to 1824 privacy, especially if one or more of these functional entities has 1825 been compromised. Likewise, all devices on the paths used for 1826 control, reporting, and measurement are also observers. 1828 8.4.1. MA Bootstrapping 1830 Section 5.1 provides the communication model for the Bootstrapping 1831 process. 1833 Although the specification of mechanisms for Bootstrapping the MA are 1834 beyond the initial LMAP work scope, designers should recognize that 1835 the Bootstrapping process is extremely powerful and could cause an MA 1836 to join a new or different LMAP system with a different Controller 1837 and Collector, or simply install new Metrics with associated 1838 Measurement Methods (for example to record DNS queries). A Bootstrap 1839 attack could result in a breach of the LMAP system with significant 1840 sensitive information exposure depending on the capabilities of the 1841 MA, so sufficient security protections are warranted. 1843 The Bootstrapping process provides sensitive information about the 1844 LMAP system and the organisation that operates it, such as 1845 o the MA's identifier (MA-ID) 1847 o the address that identifies the Control Channel, such as the 1848 Controller's FQDN 1850 o Security information for the Control Channel 1852 During the Bootstrap process for an MA located at a single 1853 subscriber's service demarcation point, the MA receives a MA-ID which 1854 is a persistent pseudonym for the Subscriber. Thus, the MA-ID is 1855 considered sensitive information because it could provide the link 1856 between Subscriber identification and Measurements Results. 1858 Also, the Bootstrap process could assign a Group-ID to the MA. The 1859 specific definition of information represented in a Group-ID is to be 1860 determined, but several examples are envisaged including use as a 1861 pseudonym for a set of Subscribers, a class of service, an access 1862 technology, or other important categories. Assignment of a Group-ID 1863 enables anonymisation sets to be formed on the basis of service 1864 type/grade/rates. Thus, the mapping between Group-ID and MA-ID is 1865 considered sensitive information. 1867 8.4.2. Controller <-> Measurement Agent 1869 The high-level communication model for interactions between the LMAP 1870 Controller and Measurement Agent is illustrated in Section 5.2. The 1871 primary purpose of this exchange is to authenticate and task a 1872 Measurement Agent with Measurement Instructions, which the 1873 Measurement Agent then acts on autonomously. 1875 Primarily IP addresses and pseudonyms (MA-ID, Group-ID) are exchanged 1876 with a capability request, then measurement-related information of 1877 interest such as the parameters, schedule, metrics, and IP addresses 1878 of measurement devices. Thus, the measurement Instruction contains 1879 sensitive information which must be secured. For example, the fact 1880 that an ISP is running additional measurements beyond the set 1881 reported externally is sensitive information, as are the additional 1882 Measurements Tasks themselves. The Measurement Schedule is also 1883 sensitive, because an attacker intending to bias the results without 1884 being detected can use this information to great advantage. 1886 An organisation operating the Controller having no service 1887 relationship with a user who hosts the Measurement Agent *could* gain 1888 real-name mapping to a public IP address through user participation 1889 in an LMAP system (this applies to the Measurement Collection 1890 protocol, as well). 1892 8.4.3. Collector <-> Measurement Agent 1894 The high-level communication model for interactions between the 1895 Measurement Agent and Collector is illustrated in Section 5.4. The 1896 primary purpose of this exchange is to authenticate and collect 1897 Measurement Results from a MA, which the MA has measured autonomously 1898 and stored. 1900 The Measurement Results are the additional sensitive information 1901 included in the Collector-MA exchange. Organisations collecting LMAP 1902 measurements have the responsibility for data control. Thus, the 1903 Results and other information communicated in the Collector protocol 1904 must be secured. 1906 8.4.4. Measurement Peer <-> Measurement Agent 1908 A Measurement Method involving Measurement Traffic raises potential 1909 privacy issues, although the specification of the mechanisms is 1910 beyond the scope of the initial LMAP work. The high-level 1911 communications model below illustrates the various exchanges to 1912 execute such a Measurement Method and store the Results. 1914 We note the potential for additional observers in the figures below 1915 by indicating the possible presence of a NAT, which has additional 1916 significance to the protocols and direction of initiation. 1918 The various messages are optional, depending on the nature of the 1919 Measurement Method. It may involve sending Measurement Traffic from 1920 the Measurement Peer to MA, MA to Measurement Peer, or both. 1921 Similarly, a second (or more) MAs may be involved. 1923 _________________ _________________ 1924 | | | | 1925 |Measurement Peer |=========== NAT ? ==========|Measurement Agent| 1926 |_________________| |_________________| 1928 <- (Key Negotiation & 1929 Encryption Setup) 1930 (Encrypted Channel -> 1931 Established) 1932 (Announce capabilities -> 1933 & status) 1934 <- (Select capabilities) 1935 ACK -> 1936 <- (Measurement Request 1937 (MA+MP IPAddrs,set of 1938 Metrics, Schedule)) 1939 ACK -> 1941 Measurement Traffic <> Measurement Traffic 1942 (may/may not be encrypted) (may/may not be encrypted) 1944 <- (Stop Measurement Task) 1946 Measurement Results -> 1947 (if applicable) 1948 <- ACK, Close 1950 This exchange primarily exposes the IP addresses of measurement 1951 devices and the inference of measurement participation from such 1952 traffic. There may be sensitive information on key points in a 1953 service provider's network included. There may also be access to 1954 measurement-related information of interest such as the Metrics, 1955 Schedule, and intermediate results carried in the Measurement Traffic 1956 (usually a set of timestamps). 1958 The Measurement Peer may be able to use traffic analysis (perhaps 1959 combined with traffic injection) to obtain interesting insights about 1960 the Subscriber. As a simple example, if the Measurement Task 1961 includes a pre-check that the end-user isn't already sending traffic, 1962 the Measurement Peer may be able to deduce when the Subscriber is 1963 away on holiday, for example. 1965 If the Measurement Traffic is unencrypted, as found in many systems 1966 today, then both timing and limited results are open to on-path 1967 observers. 1969 8.4.5. Measurement Agent 1971 Some Measurement Methods only involve a single Measurement Agent 1972 observing existing traffic. They raise potential privacy issues, 1973 although the specification of the mechanisms is beyond the scope of 1974 the initial LMAP work. 1976 The high-level communications model below illustrates the collection 1977 of user information of interest with the Measurement Agent performing 1978 the monitoring and storage of the Results. This particular exchange 1979 is for measurement of DNS Response Time, which most frequently uses 1980 UDP transport. 1982 _________________ ____________ 1983 | | | | 1984 | DNS Server |=========== NAT ? ==========*=======| User client| 1985 |_________________| ^ |____________| 1986 ______|_______ 1987 | | 1988 | Measurement | 1989 | Agent | 1990 |______________| 1992 <- Name Resolution Req 1993 (MA+MP IPAddrs, 1994 Desired Domain Name) 1995 Return Record -> 1997 In this particular example, the MA monitors DNS messages in order to 1998 measure that DNS response time. The Measurement Agent may be 1999 embedded in the user host, or it may be located in another device 2000 capable of observing user traffic. The MA learns the IP addresses of 2001 measurement devices and the intent to communicate with or access the 2002 services of a particular domain name, and perhaps also information on 2003 key points in a service provider's network, such as the address of 2004 one of its DNS servers. 2006 In principle, any of the user sensitive information of interest 2007 (listed above) can be collected and stored in the monitoring scenario 2008 and so must be secured. 2010 It would also be possible for a Measurement Agent to source the DNS 2011 query itself. But then there are few privacy concerns. 2013 8.4.6. Storage and reporting of Measurement Results 2015 Although the mechanisms for communicating results (beyond the initial 2016 Collector) are beyond the initial LMAP work scope, there are 2017 potential privacy issues related to a single organisation's storage 2018 and reporting of Measurement Results. Both storage and reporting 2019 functions can help to preserve privacy by implementing the 2020 mitigations described below. 2022 8.5. Threats 2024 This section indicates how each of the threats described in [RFC6973] 2025 apply to the LMAP entities and their communication and storage of 2026 "information of interest". Denial of Service (DOS) and other attacks 2027 described in the Security section represent threats as well, and 2028 these attacks are more effective when sensitive information 2029 protections have been compromised. 2031 8.5.1. Surveillance 2033 Section 5.1.1 of [RFC6973] describes Surveillance as the "observation 2034 or monitoring of and individual's communications or activities." 2035 Hence all Measurement Methods that measure user traffic are a form of 2036 surveillance, with inherent risks. 2038 Measurement Methods which avoid periods of user transmission 2039 indirectly produce a record of times when a subscriber or authorised 2040 user has used their network access service. 2042 Measurement Methods may also utilise and store a Subscriber's 2043 currently assigned IP address when conducting measurements that are 2044 relevant to a specific Subscriber. Since the Measurement Results are 2045 time-stamped, they could provide a record of IP address assignments 2046 over time. 2048 Either of the above pieces of information could be useful in 2049 correlation and identification, described below. 2051 8.5.2. Stored data compromise 2053 Section 5.1.2 of [RFC6973] describes Stored Data Compromise as 2054 resulting from inadequate measures to secure stored data from 2055 unauthorised or inappropriate access. For LMAP systems this includes 2056 deleting or modifying collected measurement records, as well as data 2057 theft. 2059 The primary LMAP entity subject to compromise is the repository, 2060 which stores the Measurement Results; extensive security and privacy 2061 threat mitigations are warranted. The Collector and MA also store 2062 sensitive information temporarily, and need protection. The 2063 communications between the local storage of the Collector and the 2064 repository is beyond the scope of the initial LMAP work, though this 2065 communications channel will certainly need protection as well as the 2066 mass storage itself. 2068 The LMAP Controller may have direct access to storage of Subscriber 2069 information (location, billing, service parameters, etc.) and other 2070 information which the controlling organisation considers private, and 2071 again needs protection. 2073 Note that there is tension between the desire to store all raw 2074 results in the LMAP Collector (for reproducibility and custom 2075 analysis), and the need to protect the privacy of measurement 2076 participants. Many of the compromise mitigations described in 2077 section 8.6 below are most efficient when deployed at the MA, 2078 therefore minimising the risks with stored results. 2080 8.5.3. Correlation and identification 2082 Sections 5.2.1 and 5.2.2 of [RFC6973] describe Correlation as 2083 combining various pieces of information to obtain desired 2084 characteristics of an individual, and Identification as using this 2085 combination to infer identity. 2087 The main risk is that the LMAP system could unwittingly provide a key 2088 piece of the correlation chain, starting with an unknown Subscriber's 2089 IP address and another piece of information. For example, a 2090 Subscriber utilised Internet access from 2000 to 2310 UTC, because 2091 the Measurement Tasks were deferred, or sent a name resolution for 2092 www.example.com at 2300 UTC. 2094 8.5.4. Secondary use and disclosure 2096 Sections 5.2.3 and 5.2.4 of [RFC6973] describes Secondary Use as 2097 unauthorised utilisation of an individual's information for a purpose 2098 the individual did not intend, and Disclosure is when such 2099 information is revealed causing other's notions of the individual to 2100 change, or confidentiality to be violated. 2102 Measurement Methods that measure user traffic are a form of Secondary 2103 Use, and the Subscribers' permission should be obtained beforehand. 2104 It may be necessary to obtain the measured ISP's permission to 2105 conduct measurements, for example when required by the terms and 2106 conditions of the service agreement, and notification is considered 2107 good measurement practice. 2109 For Measurement Methods that measure Measurement Traffic the 2110 Measurement Results provide some limited information about the 2111 Subscriber or ISP and could result in Secondary Uses. For example, 2112 the use of the Results in unauthorised marketing campaigns would 2113 qualify as Secondary Use. Secondary use may break national laws and 2114 regulations, and may violate individual's expectations or desires. 2116 8.6. Mitigations 2118 This section examines the mitigations listed in section 6 of 2119 [RFC6973] and their applicability to LMAP systems. Note that each 2120 section in [RFC6973] identifies the threat categories that each 2121 technique mitigates. 2123 8.6.1. Data minimisation 2125 Section 6.1 of [RFC6973] encourages collecting and storing the 2126 minimal information needed to perform a task. 2128 LMAP results can be useful for general reporting about performance 2129 and for specific troubleshooting. They need different levels of 2130 information detail, as explained in the paragraphs below. 2132 For general results, the results can be aggregated into large 2133 categories (the month of March, all subscribers West of the 2134 Mississippi River). In this case, all individual identifications 2135 (including IP address of the MA) can be excluded, and only relevant 2136 results are provided. However, this implies a filtering process to 2137 reduce the information fields, because greater detail was needed to 2138 conduct the Measurement Tasks in the first place. 2140 For troubleshooting, so that a network operator or end user can 2141 identify a performance issue or failure, potentially all the network 2142 information (IP addresses, equipment IDs, location), Measurement 2143 Schedule, service configuration, Measurement Results, and other 2144 information may assist in the process. This includes the information 2145 needed to conduct the Measurements Tasks, and represents a need where 2146 the maximum relevant information is desirable, therefore the greatest 2147 protections should be applied. This level of detail is greater than 2148 needed for general performance monitoring. 2150 As regards Measurement Methods that measure user traffic, we note 2151 that a user may give temporary permission (to enable detailed 2152 troubleshooting), but withhold permission for them in general. Here 2153 the greatest breadth of sensitive information is potentially exposed, 2154 and the maximum privacy protection must be provided. The Collector 2155 may perform pre-storage minimisation and other mitigations (below) to 2156 help preserve privacy. 2158 For MAs with access to the sensitive information of users (e.g., 2159 within a home or a personal host/handset), it is desirable for the 2160 results collection to minimise the data reported, but also to balance 2161 this desire with the needs of troubleshooting when a service 2162 subscription exists between the user and organisation operating the 2163 measurements. 2165 8.6.2. Anonymity 2167 Section 6.1.1 of [RFC6973] describes a way in which anonymity is 2168 achieved: "there must exist a set of individuals that appear to have 2169 the same attributes as the individual", defined as an "anonymity 2170 set". 2172 Experimental methods for anonymisation of user identifiable data (and 2173 so particularly applicable to Measurement Methods that measure user 2174 traffic) have been identified in [RFC6235]. However, the findings of 2175 several of the same authors is that "there is increasing evidence 2176 that anonymisation applied to network trace or flow data on its own 2177 is insufficient for many data protection applications as in [Bur10]." 2178 Essentially, the details of such Measurement Methods can only be 2179 accessed by closed organisations, and unknown injection attacks are 2180 always less expensive than the protections from them. However, some 2181 forms of summary may protect the user's sensitive information 2182 sufficiently well, and so each Metric must be evaluated in the light 2183 of privacy. 2185 The techniques in [RFC6235] could be applied more successfully in 2186 Measurement Methods that generate Measurement Traffic, where there 2187 are protections from injection attack. The successful attack would 2188 require breaking the integrity protection of the LMAP Reporting 2189 Protocol and injecting Measurement Results (known fingerprint, see 2190 section 3.2 of [RFC6973]) for inclusion with the shared and 2191 anonymised results, then fingerprinting those records to ascertain 2192 the anonymisation process. 2194 Beside anonymisation of measured Results for a specific user or 2195 provider, the value of sensitive information can be further diluted 2196 by summarising the results over many individuals or areas served by 2197 the provider. There is an opportunity enabled by forming anonymity 2198 sets [RFC6973] based on the reference path measurement points in 2199 [I-D.ietf-ippm-lmap-path]. For example, all measurements from the 2200 Subscriber device can be identified as "mp000", instead of using the 2201 IP address or other device information. The same anonymisation 2202 applies to the Internet Service Provider, where their Internet 2203 gateway would be referred to as "mp190". 2205 Another anonymisation technique is for the MA to include its Group-ID 2206 instead of its MA-ID in its Measurement Reports, with several MAs 2207 sharing the same Group-ID. 2209 8.6.3. Pseudonymity 2211 Section 6.1.2 of [RFC6973] indicates that pseudonyms, or nicknames, 2212 are a possible mitigation to revealing one's true identity, since 2213 there is no requirement to use real names in almost all protocols. 2215 A pseudonym for a measurement device's IP address could be an LMAP- 2216 unique equipment ID. However, this would likely be a permanent 2217 handle for the device, and long-term use weakens a pseudonym's power 2218 to obscure identity. 2220 8.6.4. Other mitigations 2222 Data can be de-personalised by blurring it, for example by adding 2223 synthetic data, data-swapping, or perturbing the values in ways that 2224 can be reversed or corrected. 2226 Sections 6.2 and 6.3 of [RFC6973] describe User Participation and 2227 Security, respectively. 2229 Where LMAP measurements involve devices on the Subscriber's premises 2230 or Subscriber-owned equipment, it is essential to secure the 2231 Subscriber's permission with regard to the specific information that 2232 will be collected. The informed consent of the Subscriber (and, if 2233 different, the end user) may be needed, including the specific 2234 purpose of the measurements. The approval process could involve 2235 showing the Subscriber their measured information and results before 2236 instituting periodic collection, or before all instances of 2237 collection, with the option to cancel collection temporarily or 2238 permanently. 2240 It should also be clear who is legally responsible for data 2241 protection (privacy); in some jurisdictions this role is called the 2242 'data controller'. It is always good practice to limit the time of 2243 personal information storage. 2245 Although the details of verification would be impenetrable to most 2246 subscribers, the MA could be architected as an "app" with open 2247 source-code, pre-download and embedded terms of use and agreement on 2248 measurements, and protection from code modifications usually provided 2249 by the app-stores. Further, the app itself could provide data 2250 reduction and temporary storage mitigations as appropriate and 2251 certified through code review. 2253 LMAP protocols, devices, and the information they store clearly need 2254 to be secure from unauthorised access. This is the hand-off between 2255 privacy and security considerations (Section 7). The Data Controller 2256 has the (legal) responsibility to maintain data protections described 2257 in the Subscriber's agreement and agreements with other 2258 organisations. 2260 9. IANA considerations 2262 There are no IANA considerations in this memo. 2264 10. Acknowledgments 2266 This document originated as a merger of three individual drafts: 2267 draft-eardley-lmap-terminology-02, draft-akhter-lmap-framework-00, 2268 and draft-eardley-lmap-framework-02. 2270 Thanks to Juergen Schoenwaelder for his detailed review of the 2271 terminology. Thanks to Charles Cook for a very detailed review of 2272 -02. Thanks to Barbara Stark and Ken Ko for many helpful comments 2273 about later versions. 2275 Thanks to numerous people for much discussion, directly and on the 2276 LMAP list (apologies to those unintentionally omitted): Alan Clark, 2277 Alissa Cooper, Andrea Soppera, Barbara Stark, Benoit Claise, Brian 2278 Trammell, Charles Cook, Dan Romascanu, Dave Thorne, Frode Soerensen, 2279 Greg Mirsky, Guangqing Deng, Jason Weil, Jean-Francois Tremblay, 2280 Jerome Benoit, Joachim Fabini, Juergen Schoenwaelder, Jukka Manner, 2281 Ken Ko, Lingli Deng, Mach Chen, Matt Mathis, Marc Ibrahim, Michael 2282 Bugenhagen, Michael Faath, Nalini Elkins, Radia Perlman, Rolf Winter, 2283 Sam Crawford, Sharam Hakimi, Steve Miller, Ted Lemon, Timothy Carey, 2284 Vaibhav Bajpai, Vero Zheng, William Lupton. 2286 Philip Eardley, Trevor Burbridge and Marcelo Bagnulo work in part on 2287 the Leone research project, which receives funding from the European 2288 Union Seventh Framework Programme [FP7/2007-2013] under grant 2289 agreement number 317647. 2291 11. History 2293 First WG version, copy of draft-folks-lmap-framework-00. 2295 11.1. From -00 to -01 2297 o new sub-section of possible use of Group-IDs for privacy 2299 o tweak to definition of Control protocol 2300 o fix typo in figure in S5.4 2302 11.2. From -01 to -02 2304 o change to INFORMATIONAL track (previous version had typo'd 2305 Standards track) 2307 o new definitions for Capabilities Information and Failure 2308 Information 2310 o clarify that diagrams show LMAP-level information flows. 2311 Underlying protocol could do other interactions, eg to get through 2312 NAT or for Collector to pull a Report 2314 o add hint that after a re-boot should pause random time before re- 2315 register (to avoid mass calling event) 2317 o delete the open issue "what happens if a Controller fails" (normal 2318 methods can handle) 2320 o add some extra words about multiple Tasks in one Schedule 2322 o clarify that new Schedule replaces (rather than adds to) and old 2323 one. Similarly for new configuration of Measurement Tasks or 2324 Report Channels. 2326 o clarify suppression is temporary stop; send a new Schedule to 2327 permanently stop Tasks 2329 o alter suppression so it is ACKed 2331 o add un-suppress message 2333 o expand the text on error reporting, to mention Reporting failures 2334 (as well as failures to action or execute Measurement Task & 2335 Schedule) 2337 o add some text about how to have Tasks running indefinitely 2339 o add that optionally a Report is not sent when there are no 2340 Measurement Results 2342 o add that a Measurement Task may create more than one Measurement 2343 Result 2345 o clarify /amend /expand that Reports include the "raw" Measurement 2346 Results - any pre-processing is left for lmap2.0 2348 o add some cautionary words about what if the Collector unexpectedly 2349 doesn't hear from a MA 2351 o add some extra words about the potential impact of Measurement 2352 Tasks 2354 o clarified various aspects of the privacy section 2356 o updated references 2358 o minor tweaks 2360 11.3. From -02 to -03 2362 o alignment with the Information Model [burbridge-lmap-information- 2363 model] as this is agreed as a WG document 2365 o One-off and periodic Measurement Schedules are kept separate, so 2366 that they can be updated independently 2368 o Measurement Suppression in a separate sub-section. Can now 2369 optionally include particular Measurement Tasks &/or Schedules to 2370 suppress, and start/stop time 2372 o for clarity, concept of Channel split into Control, Report and MA- 2373 to-Controller Channels 2375 o numerous editorial changes, mainly arising from a very detailed 2376 review by Charles Cook 2378 o 2380 11.4. From -03 to -04 2382 o updates following the WG Last Call, with the proposed consensus on 2383 the various issues as detailed in 2384 http://tools.ietf.org/agenda/89/slides/slides-89-lmap-2.pdf. In 2385 particular: 2387 o tweaked definitions, especially of Measurement Agent and 2388 Measurement Peer 2390 o Instruction - left to each implementation & deployment of LMAP to 2391 decide on the granularity at which an Instruction Message works 2393 o words added about overlapping Measurement Tasks (Measurement 2394 System can handle any way they choose; Report should mention if 2395 the Task overlapped with another) 2397 o Suppression: no defined impact on Passive Measurement Task; extra 2398 option to suppress on-going Active Measurement Tasks; suppression 2399 doesn't go to Measurement Peer, since they don't understand 2400 Instructions 2402 o new concept of Data Transfer Task (and therefore adjustment of the 2403 Channel concept) 2405 o enhancement of Results with Subscriber's service parameters - 2406 could be useful, don't define how but can be included in Report to 2407 various other sections 2409 o various other smaller improvements, arising from the WGLC 2411 o Appendix added with examples of Measurement Agents and Peers in 2412 various deployment scenarios. To help clarify what these terms 2413 mean. 2415 11.5. From -04 to -05 2417 o clarified various scoping comments by using the phrase "scope of 2418 initial LMAP work" (avoiding "scope of LMAP WG" since this may 2419 change in the future) 2421 o added a Configuration Protocol - allows the Controller to update 2422 the MA about information that it obtained during the bootstrapping 2423 process (for consistency with Information Model) 2425 o Removed over-detailed information about the relationship between 2426 the different items in Instruction, as this seems more appropriate 2427 for the information model. Clarified that the lists given are 2428 about the aims and not a list of information elements (these will 2429 be defined in draft-ietf-information-model). 2431 o the Measurement Method, specified as a URI to a registry entry - 2432 rather than a URN 2434 o MA configured with time limit after which, if it hasn't heard from 2435 Controller, then it stops running Measurement Tasks (rather than 2436 this being part of a Schedule) 2438 o clarified there is no distinction between how capabilities, 2439 failure and logging information are transferred (all can be when 2440 requested by Controller or by MA on its own initiative). 2442 o removed mention of Data Transfer Tasks. This abstraction is left 2443 to the information model i-d 2445 o added Deployment sub-section about Measurement Agent embedded in 2446 ISP Network 2448 o various other smaller improvements, arising from the 2nd WGLC 2450 11.6. From -05 to -06 2452 o clarified terminlogy around Measurement Methods and Tasks. Since 2453 within a Method there may be several different roles (requester 2454 and responder, for instance) 2456 o Suppression: there is now the concept of a flag (boolean) which 2457 indicates whether a Task is by default gets suppressed or not. 2458 The optional suppression message (with list of specific tasks 2459 /schedules to suppress) over-rides this flag. 2461 o The previous bullet also means there is no need to make a 2462 distinction between active and passive Measurement Tasks, so this 2463 distinction is removed. 2465 o removed Configuration Protocol - Configuration is part of the 2466 Instruction and so uses the Control Protocol. 2468 11.7. From -06 to -07 2470 o Clarifications and nits 2472 11.8. From -07 to -08 2474 o Clarifications resulting from WG 3rd LC, as discussed in 2475 https://tools.ietf.org/agenda/90/slides/slides-90-lmap-0.pdf, plus 2476 comments made in the IETF-90 meeting. 2478 o added mention of "measurement point designations" in Measurement 2479 Task configuration and Report Protocol. 2481 11.9. From -08 to -09 2483 o Clarifications and changes from the AD review (Benoit Claise) and 2484 security directorate review (Radia Perlman). 2486 11.10. From -09 to -10 2488 o More changes from the AD review (Benoit Claise). 2490 11.11. From -10 to -11 2492 o More changes from the AD review (Benoit Claise). 2494 12. Informative References 2496 [Bur10] Burkhart, M., Schatzmann, D., Trammell, B., and E. Boschi, 2497 "The Role of Network Trace anonymisation Under Attack", 2498 January 2010. 2500 [TR-069] TR-069, , "CPE WAN Management Protocol", 2501 http://www.broadband-forum.org/technical/trlist.php, 2502 November 2013. 2504 [UPnP] ISO/IEC 29341-x, , "UPnP Device Architecture and UPnP 2505 Device Control Protocols specifications", 2506 http://upnp.org/sdcps-and-certification/standards/, 2011. 2508 [RFC1035] Mockapetris, P., "Domain names - implementation and 2509 specification", STD 13, RFC 1035, November 1987. 2511 [RFC4101] Rescorla, E. and IAB, "Writing Protocol Models", RFC 4101, 2512 June 2005. 2514 [RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally 2515 Unique IDentifier (UUID) URN Namespace", RFC 4122, July 2516 2005. 2518 [RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. 2519 Bierman, "Network Configuration Protocol (NETCONF)", RFC 2520 6241, June 2011. 2522 [RFC7011] Claise, B., Trammell, B., and P. Aitken, "Specification of 2523 the IP Flow Information Export (IPFIX) Protocol for the 2524 Exchange of Flow Information", STD 77, RFC 7011, September 2525 2013. 2527 [RFC7368] Chown, T., Arkko, J., Brandt, A., Troan, O., and J. Weil, 2528 "IPv6 Home Networking Architecture Principles", RFC 7368, 2529 October 2014. 2531 [RFC7258] Farrell, S. and H. Tschofenig, "Pervasive Monitoring Is an 2532 Attack", BCP 188, RFC 7258, May 2014. 2534 [I-D.ietf-lmap-use-cases] 2535 Linsner, M., Eardley, P., Burbridge, T., and F. Sorensen, 2536 "Large-Scale Broadband Measurement Use Cases", draft-ietf- 2537 lmap-use-cases-06 (work in progress), February 2015. 2539 [I-D.ietf-ippm-metric-registry] 2540 Bagnulo, M., Claise, B., Eardley, P., Morton, A., and A. 2541 Akhter, "Registry for Performance Metrics", draft-ietf- 2542 ippm-metric-registry-02 (work in progress), February 2015. 2544 [RFC6419] Wasserman, M. and P. Seite, "Current Practices for 2545 Multiple-Interface Hosts", RFC 6419, November 2011. 2547 [RFC6887] Wing, D., Cheshire, S., Boucadair, M., Penno, R., and P. 2548 Selkirk, "Port Control Protocol (PCP)", RFC 6887, April 2549 2013. 2551 [I-D.ietf-lmap-information-model] 2552 Burbridge, T., Eardley, P., Bagnulo, M., and J. 2553 Schoenwaelder, "Information Model for Large-Scale 2554 Measurement Platforms (LMAP)", draft-ietf-lmap- 2555 information-model-03 (work in progress), January 2015. 2557 [RFC6235] Boschi, E. and B. Trammell, "IP Flow Anonymization 2558 Support", RFC 6235, May 2011. 2560 [RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J., 2561 Morris, J., Hansen, M., and R. Smith, "Privacy 2562 Considerations for Internet Protocols", RFC 6973, July 2563 2013. 2565 [I-D.ietf-ippm-lmap-path] 2566 Bagnulo, M., Burbridge, T., Crawford, S., Eardley, P., and 2567 A. Morton, "A Reference Path and Measurement Points for 2568 Large-Scale Measurement of Broadband Performance", draft- 2569 ietf-ippm-lmap-path-07 (work in progress), October 2014. 2571 [RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M. 2572 Zekauskas, "A One-way Active Measurement Protocol 2573 (OWAMP)", RFC 4656, September 2006. 2575 [RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J. 2576 Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)", 2577 RFC 5357, October 2008. 2579 [RFC3444] Pras, A. and J. Schoenwaelder, "On the Difference between 2580 Information Models and Data Models", RFC 3444, January 2581 2003. 2583 Authors' Addresses 2585 Philip Eardley 2586 BT 2587 Adastral Park, Martlesham Heath 2588 Ipswich 2589 ENGLAND 2591 Email: philip.eardley@bt.com 2593 Al Morton 2594 AT&T Labs 2595 200 Laurel Avenue South 2596 Middletown, NJ 2597 USA 2599 Email: acmorton@att.com 2601 Marcelo Bagnulo 2602 Universidad Carlos III de Madrid 2603 Av. Universidad 30 2604 Leganes, Madrid 28911 2605 SPAIN 2607 Phone: 34 91 6249500 2608 Email: marcelo@it.uc3m.es 2609 URI: http://www.it.uc3m.es 2611 Trevor Burbridge 2612 BT 2613 Adastral Park, Martlesham Heath 2614 Ipswich 2615 ENGLAND 2617 Email: trevor.burbridge@bt.com 2619 Paul Aitken 2620 Brocade 2621 Edinburgh, Scotland EH6 6LX 2622 UK 2624 Email: paitken@brocade.com 2625 Aamer Akhter 2626 LiveAction 2627 118 Timber Hitch 2628 Cary, NC 2629 USA 2631 Email: aakhter@gmail.com