idnits 2.17.1 draft-ietf-ccamp-rsvp-te-bandwidth-availability-05.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 (August 19, 2016) is 2804 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Missing Reference: 'This ID' is mentioned on line 282, but not defined -- Obsolete informational reference (is this intentional?): RFC 5226 (Obsoleted by RFC 8126) Summary: 0 errors (**), 0 flaws (~~), 2 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 Network Working Group H. Long, M. Ye 2 Internet Draft Huawei Technologies Co., Ltd 3 Intended status: Standards Track G. Mirsky 4 Ericsson 5 A.D'Alessandro 6 Telecom Italia S.p.A 7 H. Shah 8 Ciena 9 Expires: February 2017 August 19, 2016 11 Ethernet Traffic Parameters with Availability Information 12 draft-ietf-ccamp-rsvp-te-bandwidth-availability-05.txt 14 Abstract 16 A Packet switching network may contain links with variable bandwidth, 17 e.g., copper, radio, etc. The bandwidth of such links is sensitive 18 to external environment. Availability is typically used for 19 describing the link during network planning. This document 20 introduces an optional Availability TLV in Resource ReSerVation 21 Protocol - Traffic Engineer (RSVP-TE) signaling. This extension can 22 be used to set up a Label Switched Path (LSP) in a Packet Switched 23 Network (PSN) that contains links with discretely variable bandwidth. 25 Status of this Memo 27 This Internet-Draft is submitted in full conformance with the 28 provisions of BCP 78 and BCP 79. 30 Internet-Drafts are working documents of the Internet Engineering 31 Task Force (IETF), its areas, and its working groups. Note that 32 other groups may also distribute working documents as Internet- 33 Drafts. 35 Internet-Drafts are draft documents valid for a maximum of six 36 months and may be updated, replaced, or obsoleted by other documents 37 at any time. It is inappropriate to use Internet-Drafts as 38 reference material or to cite them other than as "work in progress." 40 The list of current Internet-Drafts can be accessed at 41 http://www.ietf.org/ietf/1id-abstracts.txt 43 The list of Internet-Draft Shadow Directories can be accessed at 44 http://www.ietf.org/shadow.html 45 This Internet-Draft will expire on February 19, 2017. 47 Copyright Notice 49 Copyright (c) 2016 IETF Trust and the persons identified as the 50 document authors. All rights reserved. 52 This document is subject to BCP 78 and the IETF Trust's Legal 53 Provisions Relating to IETF Documents 54 (http://trustee.ietf.org/license-info) in effect on the date of 55 publication of this document. Please review these documents 56 carefully, as they describe your rights and restrictions with 57 respect to this document. Code Components extracted from this 58 document must include Simplified BSD License text as described in 59 Section 4.e of the Trust Legal Provisions and are provided without 60 warranty as described in the Simplified BSD License. 62 Table of Contents 64 1. Introduction ................................................ 3 65 2. Overview .................................................... 4 66 3. Extension to RSVP-TE Signaling............................... 4 67 3.1. Availability TLV........................................ 4 68 3.2. Signaling Process....................................... 5 69 4. Security Considerations...................................... 6 70 5. IANA Considerations ......................................... 6 71 5.1 Ethernet Sender TSpec TLVs ............................. 6 72 6. References .................................................. 7 73 6.1. Normative References.................................... 7 74 6.2. Informative References.................................. 7 75 7. Appendix: Bandwidth Availability Example..................... 8 76 8. Acknowledgments ............................................. 9 78 Conventions used in this document 80 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 81 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 82 document are to be interpreted as described in RFC-2119 [RFC2119]. 84 The following acronyms are used in this draft: 86 RSVP-TE Resource Reservation Protocol-Traffic Engineering 88 LSP Label Switched Path 90 PSN Packet Switched Network 91 SNR Signal-to-noise Ratio 93 TLV Type Length Value 95 LSA Link State Advertisement 97 1. Introduction 99 The RSVP-TE specification [RFC3209] and GMPLS extensions [RFC3473] 100 specify the signaling message including the bandwidth request for 101 setting up a Label Switched Path in a PSN network. 103 Some data communication technologies allow seamless change of 104 maximum physical bandwidth through a set of known discrete values. 105 The parameter availability [G.827], [F.1703], [P.530] is often used 106 to describe the link capacity during network planning. The 107 availability is a time scale, which is a proportion of the operating 108 time that the requested bandwidth is ensured. A more detailed 109 example on the bandwidth availability can be found in Appendix A. 110 Assigning different availability classes to different types of 111 service over such kind of links provides more efficient planning of 112 link capacity. To set up an LSP across these links, availability 113 information is required for the nodes to verify bandwidth 114 satisfaction and make bandwidth reservation. The availability 115 information should be inherited from the availability requirements 116 of the services expected to be carried on the LSP. For example, 117 voice service usually needs "five nines" availability, while non- 118 real time services may adequately perform at four or three nines 119 availability. Since different service types may need different 120 availabilities guarantees, multiple pairs 121 may be required when signaling. 123 If the availability requirement is not specified in the signaling 124 message, the bandwidth will be reserved as the highest availability. 125 For example, the bandwidth with 99.999% availability of a link is 126 100 Mbps; the bandwidth with 99.99% availability is 200 Mbps. When a 127 video application requests for 120 Mbps without availability 128 requirement, the system will consider the request as 120 Mbps with 129 99.999% availability, while the available bandwidth with 99.999% 130 availability is only 100 Mbps, therefore the LSP path cannot be set 131 up. But in fact, video application doesn't need 99.999% availability; 132 99.99% availability is enough. In this case, the LSP could be set up 133 if availability is specified in the signaling message. 135 To fulfill LSP setup by signaling in these scenarios, this document 136 specifies an Availability TLV. The Availability TLV can be 137 applicable to any kind of physical links with variable discrete 138 bandwidth, such as microwave or DSL. Multiple Availability TLVs 139 together with multiple Ethernet Bandwidth Profiles can be carried in 140 the Ethernet SENDER_TSPEC object. 142 2. Overview 144 A PSN tunnel may span one or more links in a network. To setup a 145 Label Switched Path (LSP), a node may collect link information which 146 is spread in routing message, e.g., OSPF TE LSA message, by network 147 nodes to get to know about the network topology, and calculate out 148 an LSP route based on the network topology, and send the calculated 149 LSP route to signaling to initiate a PATH/RESV message for setting 150 up the LSP. 152 In case that there is(are) link(s) with variable discrete bandwidth 153 in a network, a requirement list should be 154 specified for an LSP. Each pair in the 155 list means that listed bandwidth with specified availability is 156 required. The list could be inherited from the results of service 157 planning for the LSP. 159 A node which has link(s) with variable discrete bandwidth attached 160 should contain a information list in its 161 OSPF TE LSA messages. The list provides the mapping between the link 162 nominal bandwidth and its availability level. This information is 163 used for path calculation by the node(s). The routing extension for 164 availability can be found in [ARTE]. 166 When a node initiates a PATH/RESV signaling to set up an LSP, the 167 PATH message should carry the requirement 168 list as bandwidth request. Intermediate node(s) will allocate the 169 bandwidth resource for each availability requirement from the 170 remaining bandwidth with corresponding availability. An error 171 message may be returned if any request 172 cannot be satisfied. 174 3. Extension to RSVP-TE Signaling 176 3.1. Availability TLV 178 An Availability TLV is defined as a TLV of the Ethernet 179 SENDEDR_TSPEC object [RFC6003] in this document. The Ethernet 180 SENDER_TSPEC object MAY include more than one Availability TLV. The 181 Availability TLV has the following format: 183 0 1 2 3 184 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 185 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 186 | Index | Reserved | 187 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 188 | Availability | 189 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 191 Figure 1: Availability TLV 193 Index (1 octet): 195 The Availability TLV MUST come along with Ethernet Bandwidth 196 Profile TLV. If the bandwidth requirements in the multiple 197 Ethernet Bandwidth Profile TLVs have different Availability 198 requirements, multiple Availability TLVs SHOULD be carried. In 199 such a case, the Availability TLV has one to one correspondence 200 with Ethernet Bandwidth Profile TLV by having the same value of 201 Index field. If all the bandwidth requirements in the Ethernet 202 Bandwidth Profile have the same Availability requirement, one 203 Availability TLV SHOULD be carried. In this case, the Index field 204 is set to 0. 206 Reserved (3 octets): These bits SHOULD be set to zero when sent 207 and MUST be ignored when received. 209 Availability (4 octets): a 32-bit floating number describes the 210 decimal value of availability requirement for this bandwidth 211 request. The value MUST be less than 1and is usually expressed in 212 the value of 0.99/0.999/0.9999/0.99999. 214 3.2. Signaling Process 216 The source node initiates PATH messages which carry a number of 217 bandwidth request information, including one or more Ethernet 218 Bandwidth Profile TLVs and one or more Availability TLVs. Each 219 Ethernet Bandwidth Profile TLV corresponds to an availability 220 parameter in the Availability TLV. 222 The intermediate and destination nodes check whether they can 223 satisfy the bandwidth requirements by comparing each bandwidth 224 requirement inside the SENDER_TSPEC objects with the remaining link 225 sub-bandwidth resource with respective availability guarantee on the 226 local link when received the PATH message. 228 o If all requirements can be 229 satisfied (the requested bandwidth under each availability 230 parameter is smaller than or equal to the remaining bandwidth 231 under the corresponding availability parameter on its local 232 link), it SHOULD reserve the bandwidth resource from each 233 remaining sub-bandwidth portion on its local link to set up 234 this LSP. Optionally, the higher availability bandwidth can be 235 allocated to lower availability request when the lower 236 availability bandwidth cannot satisfy the request. 238 o If at least one requirement cannot 239 be satisfied, it SHOULD generate PathErr message with the error 240 code "Admission Control Error" and the error value "Requested 241 Bandwidth Unavailable" (see [RFC2205]). 243 If two LSPs request for the bandwidth with the same availability 244 requirement, a way to resolve the contention is comparing the node 245 ID, the node with the higher node ID will win the contention. More 246 details can be found in [RFC3473]. 248 If a node does not support Availability TLV, it SHOULD generate 249 PathErr message with the error code "Extended Class-Type Error" and 250 the error value "Class-Type mismatch" (see [RFC2205]). 252 4. Security Considerations 254 This document does not introduce new security considerations to the 255 existing RSVP-TE signaling protocol. [RFC5920] provides an overview 256 of security vulnerabilities and protection mechanisms for the GMPLS 257 control plane. 259 5. IANA Considerations 261 IANA maintains registries and sub-registries for RSVP-TE used by 262 GMPLS. IANA is requested to make allocations from these registries 263 as set out in the following sections. 265 5.1 Ethernet Sender TSpec TLVs 267 IANA maintains a registry of GMPLS parameters called "Generalized 268 Multi-Protocol Label Switching (GMPLS) Signaling Parameters". 270 IANA has created a sub-registry called "Ethernet Sender TSpec TLVs / 271 Ethernet Flowspec TLVs" to contain the TLV type values for TLVs 272 carried in the Ethernet SENDER_TSPEC object. The sub-registry is 273 needed to be updated to include the Availability TLV which is 274 defined as follow. This document proposes a suggested value for the 275 Availability sub-TLV; it is recommended that the suggested value be 276 granted by IANA. 278 Type Description Reference 280 ----- ----------------------------------- --------- 282 0x04 Availability [This ID] 284 The registration procedure for this registry is Standards Action as 285 defined in [RFC5226]. 287 6. References 289 6.1. Normative References 291 [RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and 292 S.Jamin, "Resource ReSerVation Protocol (RSVP) - Version 1 293 Functional Specification", RFC 2205, September 1997. 295 [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, 296 V.,and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP 297 Tunnels", RFC 3209, December 2001. 299 [RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching 300 (GMPLS) Signaling Resource ReserVation Protocol-Traffic 301 Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. 303 [RFC6003] Papadimitriou, D. "Ethernet Traffic Parameters", RFC 6003, 304 October 2010. 306 6.2. Informative References 308 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 309 Requirement Levels", RFC 2119, March 1997. 311 [RFC5226] Narten,T. and H. Alvestrand, "Guidelines for Writing an 312 IANA Considerations Section in RFCs", RFC 5226, May 2008. 314 [RFC5920] Fang, L., "Security Framework for MPLS and GMPLS Networks", 315 RFC 5920, July 2010. 317 [G.827] ITU-T Recommendation, "Availability performance parameters 318 and objectives for end-to-end international constant bit- 319 rate digital paths", September, 2003. 321 [F.1703] ITU-R Recommendation, "Availability objectives for real 322 digital fixed wireless links used in 27 500 km 323 hypothetical reference paths and connections", January, 324 2005. 326 [P.530] ITU-R Recommendation," Propagation data and prediction 327 methods required for the design of terrestrial line-of- 328 sight systems", February, 2012 330 [EN 302 217] ETSI standard, "Fixed Radio Systems; Characteristics 331 and requirements for point-to-point equipment and 332 antennas", April, 2009 334 [ARTE] H., Long, M., Ye, Mirsky, G., Alessandro, A., Shah, H., 335 "OSPF Routing Extension for Links with Variable Discrete 336 Bandwidth", Work in Progress, June, 2015 338 7. Appendix: Bandwidth Availability Example 340 In mobile backhaul network, microwave links are very popular for 341 providing connection of last hops. In case of heavy rain, to 342 maintain the link connectivity, the microwave link MAY lower the 343 modulation level since demodulating the lower modulation level needs 344 a lower Signal-to-Noise Ratio (SNR). This is called adaptive 345 modulation technology [EN 302 217]. However, a lower modulation 346 level also means lower link bandwidth. When link bandwidth is 347 reduced because of modulation down-shifting, high-priority traffic 348 can be maintained, while lower-priority traffic is dropped. 349 Similarly, the copper links MAY change their link bandwidth due to 350 external interference. 352 Presuming that a link has three discrete bandwidth levels: 354 The link bandwidth under modulation level 1, e.g., QPSK, is 100 Mbps; 356 The link bandwidth under modulation level 2, e.g., 16QAM, is 200 357 Mbps; 359 The link bandwidth under modulation level 3, e.g., 256QAM, is 400 360 Mbps. 362 In sunny day, the modulation level 3 can be used to achieve 400 Mbps 363 link bandwidth. 365 A light rain with X mm/h rate triggers the system to change the 366 modulation level from level 3 to level 2, with bandwidth changing 367 from 400 Mbps to 200 Mbps. The probability of X mm/h rain in the 368 local area is 52 minutes in a year. Then the dropped 200 Mbps 369 bandwidth has 99.99% availability. 371 A heavy rain with Y(Y>X) mm/h rate triggers the system to change the 372 modulation level from level 2 to level 1, with bandwidth changing 373 from 200 Mbps to 100 Mbps. The probability of Y mm/h rain in the 374 local area is 26 minutes in a year. Then the dropped 100 Mbps 375 bandwidth has 99.995% availability. 377 For the 100M bandwidth of the modulation level 1, only the extreme 378 weather condition can cause the whole system unavailable, which only 379 happens for 5 minutes in a year. So the 100 Mbps bandwidth of the 380 modulation level 1 owns the availability of 99.999%. 382 In a word, the maximum bandwidth is 400 Mbps. According to the 383 weather condition, the sub-bandwidth and its availability are shown 384 as follows: 386 Sub-bandwidth(Mbps) Availability 388 ------------------ ------------ 390 200 99.99% 392 100 99.995% 394 100 99.999% 396 8. Acknowledgments 398 The authors would like to thank Khuzema Pithewan, Lou Berger, Yuji 399 Tochio, Dieter Beller, and Autumn Liu for their comments on the 400 document. 402 Authors' Addresses 403 Hao Long 404 Huawei Technologies Co., Ltd. 405 No.1899, Xiyuan Avenue, Hi-tech Western District 406 Chengdu 611731, P.R.China 408 Phone: +86-18615778750 409 Email: longhao@huawei.com 411 Min Ye (editor) 412 Huawei Technologies Co., Ltd. 413 No.1899, Xiyuan Avenue, Hi-tech Western District 414 Chengdu 611731, P.R.China 416 Email: amy.yemin@huawei.com 418 Greg Mirsky (editor) 419 Ericsson 421 Email: gregory.mirsky@ericsson.com 423 Alessandro D'Alessandro 424 Telecom Italia S.p.A 426 Email: alessandro.dalessandro@telecomitalia.it 428 Himanshu Shah 429 Ciena Corp. 430 3939 North First Street 431 San Jose, CA 95134 432 US 434 Email: hshah@ciena.com