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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Unused Reference: 'RFC4941' is defined on line 665, but no explicit reference was found in the text ** Downref: Normative reference to an Informational RFC: RFC 3610 ** Obsolete normative reference: RFC 3633 (Obsoleted by RFC 8415) ** Downref: Normative reference to an Informational RFC: RFC 4541 ** Obsolete normative reference: RFC 4941 (Obsoleted by RFC 8981) == Outdated reference: A later version (-16) exists of draft-ietf-6man-default-iids-02 Summary: 4 errors (**), 0 flaws (~~), 3 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 6Lo Working Group P. Mariager 3 Internet-Draft J. Petersen, Ed. 4 Intended status: Standards Track RTX A/S 5 Expires: July 31, 2015 Z. Shelby 6 ARM 7 M. Van de Logt 8 Gigaset Communications GmbH 9 D. Barthel 10 Orange Labs 11 January 27, 2015 13 Transmission of IPv6 Packets over DECT Ultra Low Energy 14 draft-ietf-6lo-dect-ule-01 16 Abstract 18 DECT Ultra Low Energy is a low power air interface technology that is 19 defined by the DECT Forum and specified by ETSI. 21 The DECT air interface technology has been used world-wide in 22 communication devices for more than 20 years, primarily carrying 23 voice for cordless telephony but has also been deployed for data 24 centric services. 26 The DECT Ultra Low Energy is a recent addition to the DECT interface 27 primarily intended for low-bandwidth, low-power applications such as 28 sensor devices, smart meters, home automation etc. As the DECT Ultra 29 Low Energy interface inherits many of the capabilities from DECT, it 30 benefits from long range, interference free operation, world wide 31 reserved frequency band, low silicon prices and maturity. There is 32 an added value in the ability to communicate with IPv6 over DECT ULE 33 such as for Internet of Things applications. 35 This document describes how IPv6 is transported over DECT ULE using 36 6LoWPAN techniques. 38 Status of This Memo 40 This Internet-Draft is submitted in full conformance with the 41 provisions of BCP 78 and BCP 79. 43 Internet-Drafts are working documents of the Internet Engineering 44 Task Force (IETF). Note that other groups may also distribute 45 working documents as Internet-Drafts. The list of current Internet- 46 Drafts is at http://datatracker.ietf.org/drafts/current/. 48 Internet-Drafts are draft documents valid for a maximum of six months 49 and may be updated, replaced, or obsoleted by other documents at any 50 time. It is inappropriate to use Internet-Drafts as reference 51 material or to cite them other than as "work in progress." 53 This Internet-Draft will expire on July 31, 2015. 55 Copyright Notice 57 Copyright (c) 2015 IETF Trust and the persons identified as the 58 document authors. All rights reserved. 60 This document is subject to BCP 78 and the IETF Trust's Legal 61 Provisions Relating to IETF Documents 62 (http://trustee.ietf.org/license-info) in effect on the date of 63 publication of this document. Please review these documents 64 carefully, as they describe your rights and restrictions with respect 65 to this document. Code Components extracted from this document must 66 include Simplified BSD License text as described in Section 4.e of 67 the Trust Legal Provisions and are provided without warranty as 68 described in the Simplified BSD License. 70 Table of Contents 72 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 73 1.1. Requirements Notation . . . . . . . . . . . . . . . . . . 3 74 1.2. Terms Used . . . . . . . . . . . . . . . . . . . . . . . 3 75 2. DECT Ultra Low Energy . . . . . . . . . . . . . . . . . . . . 4 76 2.1. The DECT ULE Protocol Stack . . . . . . . . . . . . . . . 4 77 2.2. Link layer roles and topology . . . . . . . . . . . . . . 6 78 2.3. Addressing Model . . . . . . . . . . . . . . . . . . . . 6 79 2.4. MTU Considerations . . . . . . . . . . . . . . . . . . . 7 80 2.5. Additional Considerations . . . . . . . . . . . . . . . . 7 81 3. Specification of IPv6 over DECT ULE . . . . . . . . . . . . . 7 82 3.1. Protocol stack . . . . . . . . . . . . . . . . . . . . . 8 83 3.2. Link model . . . . . . . . . . . . . . . . . . . . . . . 8 84 3.3. Internet connectivity scenarios . . . . . . . . . . . . . 12 85 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 86 5. Security Considerations . . . . . . . . . . . . . . . . . . . 13 87 6. ETSI Considerations . . . . . . . . . . . . . . . . . . . . . 14 88 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14 89 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 14 90 8.1. Normative References . . . . . . . . . . . . . . . . . . 14 91 8.2. Informative References . . . . . . . . . . . . . . . . . 15 92 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 94 1. Introduction 96 DECT Ultra Low Energy (DECT ULE or just ULE) is an air interface 97 technology building on the key fundamentals of traditional DECT / 98 CAT-iq but with specific changes to significantly reduce the power 99 consumption on the expense of data throughput. DECT ULE devices with 100 requirements to power consumption will operate on special power 101 optimized silicon, but can connect to a DECT Gateway supporting 102 traditional DECT / CAT-iq for cordless telephony and data as well as 103 the ULE extensions. DECT terminology operates with two major role 104 definitions: The Portable Part (PP) is the power constrained device, 105 while the Fixed Part (FP) is the Gateway or base station. This FP 106 may be connected to the Internet. An example of a use case for DECT 107 ULE is a home security sensor transmitting small amounts of data (few 108 bytes) at periodic intervals through the FP, but is able to wake up 109 upon an external event (burglar) and communicate with the FP. 110 Another example incorporating both DECT ULE as well as traditional 111 CAT-iq telephony is an elderly pendant (broche) which can transmit 112 periodic status messages to a care provider using very little 113 battery, but in the event of urgency, the elderly person can 114 establish a voice connection through the pendant to an alarm service. 115 It is expected that DECT ULE will be integrated into many residential 116 gateways, as many of these already implements DECT CAT-iq for 117 cordless telephony. DECT ULE can be added as a software option for 118 the FP. It is desirable to consider IPv6 for DECT ULE devices due to 119 the large address space and well-known infrastructure. This document 120 describes how IPv6 is used on DECT ULE links to optimize power while 121 maintaining the many benefits of IPv6 transmission. [RFC4944] 122 specifies the transmission of IPv6 over IEEE 802.15.4. DECT ULE has 123 in many ways similar characteristics of IEEE 802.15.4, but also 124 differences. Many of the mechanisms defined in [RFC4944] can be 125 applied to the transmission of IPv6 on DECT ULE links. 127 This document specifies how to map IPv6 over DECT ULE inspired by 128 [RFC4944]. 130 1.1. Requirements Notation 132 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 133 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 134 document are to be interpreted as described in [RFC2119]. 136 1.2. Terms Used 138 PP: DECT Portable Part, typically the sensor node 140 FP: DECT Fixed Part, the gateway 141 LLME: Lower Layer Management Entity 143 NWK: Network 145 PVC: Permanent Virtual Circuit 147 6LN: DECT Portable part having a role as defined in [RFC6775] 149 6LBR: DECT Fixed Part having a role as defined in [RFC6775] 151 2. DECT Ultra Low Energy 153 DECT ULE is a low power air interface technology that is designed to 154 support both circuit switched for service, such as voice 155 communication, and for packet mode data services at modest data rate. 156 This draft is only addressing the packet mode data service of DECT 157 ULE. 159 2.1. The DECT ULE Protocol Stack 161 The DECT ULE protocol stack consists of the PHY layer operating at 162 frequencies in the 1880 - 1920 MHz frequency band depending on the 163 region and uses a symbol rate of 1.152 Mbps. Radio bearers are 164 allocated by use of FDMA/TDMA/TDD technics. 166 In its generic network topology, DECT is defined as a cellular 167 network technology. However, the most common configuration is a star 168 network with a single FP defining the network with a number of PP 169 attached. The MAC layer supports both traditional DECT as this is 170 used for services like discovery, pairing, security features etc. 171 All these features have been reused from DECT. 173 The DECT ULE device can switch to the ULE mode of operation, 174 utilizing the new ULE MAC layer features. The DECT ULE Data Link 175 Control (DLC) provides multiplexing as well as segmentation and re- 176 assembly for larger packets from layers above. The DECT ULE layer 177 also implements per-message authentication and encryption. The DLC 178 layer ensures packet integrity and preserves packet order, but 179 delivery is based on best effort. 181 The current DECT ULE MAC layer standard supports low bandwidth data 182 broadcast. However the usage of this broadcast service has not yet 183 been standardized for higher layers. This document is not 184 considering usage of this DECT ULE MAC broadcast service in current 185 version. 187 In general, communication sessions can be initiated from both FP and 188 PP side. Depending on power down modes employed in the PP, latency 189 may occur when initiating sessions from FP side. MAC layer 190 communication can either take place using connection oriented packet 191 transfer with low overhead for short sessions or take place using 192 connection oriented bearers including media reservation. The MAC 193 layer autonomously selects the radio spectrum positions that are 194 available within the band and can rearrange these to avoid 195 interference. The MAC layer has built-in retransmission procedures 196 in order to improve transmission reliability. 198 The DECT ULE device will typically incorporate an Application 199 Programmers Interface (API) as well as common elements known as 200 Generic Access Profile (GAP) for enrolling into the network. The 201 DECT ULE stack establishes a permanent virtual circuit (PVC) for the 202 application layers and provides support for a range of different 203 application protocols. The used application protocol is negotiated 204 between the PP and FP when the PVC communication service is 205 established. This draft defines 6LoWPAN as one of the possible 206 protocols to negotiate. 208 +----------------------------------------+ 209 | Applications | 210 +----------------------------------------+ 211 | Generic Access | ULE Profile | 212 | Profile | | 213 +----------------------------------------+ 214 | DECT/Service API | ULE Data API | 215 +--------------------+-------------------+ 216 | LLME | NWK (MM,CC)| | 217 +--------------------+-------------------+ 218 | DECT DLC | DECT ULE DLC | 219 +--------------------+-------------------+ 220 | MAC Layer | 221 +--------------------+-------------------+ 222 | Physical Layer | 223 +--------------------+-------------------+ 224 (C-plane) (U-plane) 226 Figure 1: DECT ULE Protocol Stack 228 The DECT ULE stack can be divided into control (C-plane) and user- 229 data (U-plane) parts shown to the left and to the right in figure 1, 230 respectively. 232 2.2. Link layer roles and topology 234 A FP is assumed to be less constrained than a PP. Hence, in the 235 primary scenario FP and PP will act as 6LBR and a 6LN, respectively. 236 This document does only address this primary scenario. 238 In DECT ULE, at link layer the communication only takes place between 239 a FP and a PP. A FP is able to handle multiple simultaneous 240 connections with a number of PP. Hence, in a DECT ULE network using 241 IPv6, a radio hop is equivalent to an IPv6 link and vice versa. 243 [DECT ULE PP]-----\ /-----[DECT ULE PP] 244 \ / 245 [DECT ULE PP]-------+[DECT ULE FP]+-------[DECT ULE PP] 246 / \ 247 [DECT ULE PP]-----/ \-----[DECT ULE PP] 249 Figure 2: DECT ULE star topology 251 DECT ULE repeaters are not considered in this document. 253 2.3. Addressing Model 255 Each DECT PP is assigned an (International Portable Equipment 256 Identity) during manufacturing. This identity has the size of 40 257 bits and is DECT globally unique for the PP and can be used to 258 constitute the MAC address. However, it cannot be used to derive a 259 globally unique IID. 261 When bound to a FP, a PP is assigned a 20 bit TPUI (Temporary 262 Portable User Identity) which is unique within the FP. This TPUI is 263 used for addressing (layer 2) in messages between FP and PP. 265 Each DECT FP is assigned a (Radio Fixed Part Identity) during 266 manufacturing. This identity has the size of 40 bits and is globally 267 unique for a FP and can be used to constitute the MAC address. 268 However, it cannot be used to derive a globally unique IID. 270 Alternatively each DECT PP and DECT FP can be assigned a unique 271 (IEEE) MAC-48 address additionally to the DECT identities to be used 272 by the 6LoWPAN. With such an approach, the FP and PP have to 273 implement a mapping between used MAC-48 addresses and DECT 274 identities. 276 2.4. MTU Considerations 278 Generally the DECT ULE FP and PP may be generating data that fits 279 into a single MAC Layer packet (38 bytes) for periodically 280 transferred information, depending on application. IP data packets 281 may be much larger and hence MTU size should be the size of the IP 282 data packet. The DECT ULE DLC procedures supports segmentation and 283 reassembly of any MTU size below 65536 bytes, but most 284 implementations do only support smaller values. The default MTU size 285 in DECT ULE is 500 octets, but it is assumed it is configured to fit 286 the requirements from IPv6 data packets, hence [RFC4944] 287 fragmentation/reassembly is not required. 289 It is expected that the LOWPAN_IPHC packet will fulfill all the 290 requirements for header compression without spending unnecessary 291 overhead for mesh addressing. 293 It is important to realize that the usage of larger packets will be 294 on the expense of battery life, as a large packet inside the DECT ULE 295 stack will be fragmented into several or many MAC layer packets, each 296 consuming power to transmit / receive. 298 2.5. Additional Considerations 300 The DECT ULE standard allows PP to be registered (bind) to multiple 301 FP and roaming between these FP. This draft does not consider the 302 scenarios of PP roaming between multiple FP. The use of repeater 303 functionality is also not considered in this draft. 305 3. Specification of IPv6 over DECT ULE 307 Before any IP-layer communications can take place over DECT ULE, DECT 308 ULE enabled nodes such as 6LNs and 6LBRs have to find each other and 309 establish a suitable link-layer connection. The obtain-access-rights 310 registration and location registration procedures are documented by 311 ETSI in the specifications [EN300.175-part1-7] and [TS102.939-1]. 313 DECT ULE technology sets strict requirements for low power 314 consumption and thus limits the allowed protocol overhead. 6LoWPAN 315 standards [RFC4944], [RFC6775], and [RFC6282] provide useful 316 functionality for reducing overhead which can be applied to DECT ULE. 317 This functionality comprises link-local IPv6 addresses and stateless 318 IPv6 address autoconfiguration, Neighbor Discovery and header 319 compression. 321 The ULE 6LoWPAN adaptation layer can run directly on this U-plane DLC 322 layer. Figure 3 illustrates IPv6 over DECT ULE stack. 324 A significant difference between IEEE 802.15.4 and DECT ULE is that 325 the former supports both star and mesh topology (and requires a 326 routing protocol), whereas DECT ULE in it's primary configuration 327 does not support the formation of multihop networks at the link 328 layer. In consequence, the mesh header defined in [RFC4944] for mesh 329 under routing MUST NOT be used in DECT ULE networks. In addition, a 330 DECT ULE PP node MUST NOT play the role of a 6LoWPAN Router (6LR). 332 3.1. Protocol stack 334 In order to enable transmission of IPv6 packets over DECT ULE, a 335 Permanent Virtual Circuit (PVC) has to be opened between FP and PP. 336 This MUST be done by setting up a service call from PP to FP. The PP 337 SHALL specify the <> in a service-change (other) 338 message before sending a service-change (resume) message as defined 339 in [TS102.939-1]. The <> SHALL define the ULE 340 Application Protocol Identifier to 0x06 and the MTU size to 1280 341 octets or larger. The FP MUST send a service-change-accept (resume) 342 containing a valid paging descriptor. The PP MUST be pageable. 344 +-------------------+ 345 | UDP/TCP/other | 346 +-------------------+ 347 | IPv6 | 348 +-------------------+ 349 |6LoWPAN adapted to | 350 | DECT ULE | 351 +-------------------+ 352 | DECT ULE DLC | 353 +-------------------+ 354 | DECT ULE MAC | 355 +-------------------+ 356 | DECT ULE PHY | 357 +-------------------+ 359 Figure 3: IPv6 over DECT ULE Stack 361 3.2. Link model 363 The general model is that IPv6 is layer 3 and DECT ULE MAC+DLC is 364 layer 2. The DECT ULE implements fragmentation and reassembly 365 functionality and [RFC4944] fragmentation and reassembly function 366 MUST NOT be used. Since IPv6 requires MTU size of at least 1280 367 octets, the DECT ULE connection (PVC) MUST be configured with 368 equivalent MTU size. 370 This specification also assumes the IPv6 header compression format 371 specified in [RFC6282]. It is also assumed that the IPv6 payload 372 length can be inferred from the ULE DLC packet length and the IID 373 value inferred from the link-layer address. 375 Due to DECT ULE star topology, each branch of the star is considered 376 to be an individual link and thus the PPs cannot directly hear one 377 another and cannot talk to one another with link-local addresses. 378 However, the FP acts as a 6LBR for communication between the PPs. 379 After the FP and PPs have connected at the DECT ULE level, the link 380 can be considered up and IPv6 address configuration and transmission 381 can begin. The FP ensures address collisions do not occur. 383 3.2.1. Stateless address autoconfiguration 385 A DECT ULE 6LN performs stateless address autoconfiguration as per 386 [RFC4862]. A 64-bit Interface identifier (IID) for a DECT ULE 387 interface MAY be formed by utilizing a MAC-48 device address as 388 defined in [RFC2464] "IPv6 over Ethernet" specification. 389 Alternatively, the DECT device addresses IPEI, RFPI or TPUI, MAY be 390 used instead to derive the IID. 392 As defined in [RFC4291], the IPv6 link-local address for a DECT ULE 393 node is formed by appending the IID, to the prefix FE80::/64, as 394 shown in Figure 4. 396 10 bits 54 bits 64 bits 397 +----------+-----------------+----------------------+ 398 |1111111010| zeros | Interface Identifier | 399 +----------+-----------------+----------------------+ 401 Figure 4: IPv6 link-local address in DECT ULE 403 A 6LN MUST join the all-nodes multicast address. 405 After link-local address configuration, 6LN sends Router Solicitation 406 messages as described in [RFC4861] Section 6.3.7. 408 For non-link-local addresses a 64-bit IID MAY be formed by utilizing 409 a MAC-48 device address. Alternatively, a randomly generated IID 410 (see Section 3.2.2) can be used instead, for example, as discussed in 411 [I-D.ietf-6man-default-iids]. The non-link-local addresses 6LN 412 generates must be registered with 6LBR as described in Section 3.2.2. 414 Only if the device address is known to be a public address the 415 "Universal/Local" bit can be set to 1 [RFC4291]. 417 The means for a 6LBR to obtain an IPv6 prefix for numbering the DECT 418 ULE network is out of scope of this document, but can be, for 419 example, accomplished via DHCPv6 Prefix Delegation [RFC3633] or by 420 using Unique Local IPv6 Unicast Addresses (ULA) [RFC4193]. Due to 421 the link model of the DECT ULE the 6LBR MUST set the "on-link" flag 422 (L) to zero in the Prefix Information Option [RFC4861]. This will 423 cause 6LNs to always send packets to the 6LBR, including the case 424 when the destination is another 6LN using the same prefix. 426 3.2.2. Neighbor discovery 428 'Neighbor Discovery Optimization for IPv6 over Low-Power Wireless 429 Personal Area Networks (6LoWPANs)' [RFC6775] describes the neighbor 430 discovery approach as adapted for use in several 6LoWPAN topologies, 431 including the mesh topology. As DECT ULE is considered not to 432 support mesh networks, hence only those aspects that apply to a star 433 topology are considered. 435 The following aspects of the Neighbor Discovery optimizations 436 [RFC6775] are applicable to DECT ULE 6LNs: 438 1. For sending Router Solicitations and processing Router 439 Advertisements the DECT ULE 6LNs MUST, respectively, follow Sections 440 5.3 and 5.4 of the [RFC6775]. 442 2. A DECT ULE 6LN SHOULD NOT register its link-local address. A 443 DECT ULE 6LN MUST register its non-link-local addresses with the 6LBR 444 by sending a Neighbor Solicitation (NS) message with the Address 445 Registration Option (ARO) and process the Neighbor Advertisement (NA) 446 accordingly. The NS with the ARO option MUST be sent irrespective of 447 the method used to generate the IID. The 6LN MUST register only one 448 IPv6 address per available IPv6 prefix. 450 3.2.3. Unicast and Multicast address mapping 452 The DECT MAC layer broadcast service is considered inadequate for IP 453 multicast. 455 Hence traffic is always unicast between two DECT ULE nodes. Even in 456 the case where a 6LBR is attached to multiple 6LNs, the 6LBR cannot 457 do a multicast to all the connected 6LNs. If the 6LBR needs to send 458 a multicast packet to all its 6LNs, it has to replicate the packet 459 and unicast it on each link. However, this may not be energy- 460 efficient and particular care must be taken if the FP is battery- 461 powered. In the opposite direction, a 6LN can only transmit data to 462 or through the 6LBR. Hence, when a 6LN needs to transmit an IPv6 463 multicast packet, the 6LN will unicast the corresponding DECT ULE 464 packet to the 6LBR. The 6LBR will then forward the multicast packet 465 to other 6LNs. To avoid excess of unwanted multicast traffic being 466 sent to 6LNs, the 6LBR SHOULD implement MLD Snooping feature 467 [RFC4541]. 469 3.2.4. Header Compression 471 Header compression as defined in [RFC6282], which specifies the 472 compression format for IPv6 datagrams on top of IEEE 802.15.4, is 473 REQUIRED in this document as the basis for IPv6 header compression on 474 top of DECT ULE. All headers MUST be compressed according to 475 [RFC6282] encoding formats. The DECT ULE's star topology structure 476 and ARO can be exploited in order to provide a mechanism for IID 477 compression. The following text describes the principles of IPv6 478 address compression on top of DECT ULE. 480 3.2.4.1. Link-local Header Compression 482 In a link-local communication terminated at 6LN and 6LBR, both the 483 IPv6 source and destination addresses MUST be elided, since the node 484 knows that the packet is destined for it even if the packet does not 485 have destination IPv6 address. A node SHALL learn the IID of the 486 other endpoint of each DECT ULE connection it participates in. By 487 exploiting this information, a node that receives a PDU containing an 488 IPv6 packet can infer the corresponding IPv6 source address. A node 489 MUST maintain a Neighbor Cache, in which the entries include both the 490 IID of the neighbor and the Device Address that identifies the 491 neighbor. For the type of communication considered in this 492 paragraph, the following settings MUST be used in the IPv6 compressed 493 header: CID=0, SAC=0, SAM=11, DAC=0, DAM=11. 495 3.2.4.2. Non-link-local Header Compression 497 To enable efficient header compression, the 6LBR MUST include 6LoWPAN 498 Context Option (6CO) [RFC6775] for all prefixes the 6LBR advertises 499 in Router Advertisements for use in stateless address 500 autoconfiguration. 502 When a 6LN transmits an IPv6 packet to a destination using global 503 Unicast IPv6 addresses, if a context is defined for the prefix of the 504 6LNs global IPv6 address, the 6LN MUST indicate this context in the 505 corresponding source fields of the compressed IPv6 header as per 506 Section 3.1 of [RFC6282], and MUST elide the IPv6 source address. 507 For this, the 6LN MUST use the following settings in the IPv6 508 compressed header: CID=1, SAC=1, SAM=11. In this case, the 6LBR can 509 infer the elided IPv6 source address since 1) the 6LBR has previously 510 assigned the prefix to the 6LNs; and 2) the 6LBR maintains a Neighbor 511 Cache that relates the Device Address and the IID of the 512 corresponding PP. If a context is defined for the IPv6 destination 513 address, the 6LN MUST also indicate this context in the corresponding 514 destination fields of the compressed IPv6 header, and MUST elide the 515 prefix of the destination IPv6 address. For this, the 6LN MUST set 516 the DAM field of the compressed IPv6 header as CID=1, DAC=1 and 517 DAM=01 or DAM=11. Note that when a context is defined for the IPv6 518 destination address, the 6LBR can infer the elided destination prefix 519 by using the context. 521 When a 6LBR receives a IPv6 packet having a global Unicast IPv6 522 address, and the destination of the packet is a 6LN, if a context is 523 defined for the prefix of the 6LN's global IPv6 address, the 6LBR 524 MUST indicate this context in the corresponding destination fields of 525 the compressed IPv6 header, and MUST elide the IPv6 destination 526 address of the packet before forwarding it to the 6LN. For this, the 527 6LBR MUST set the DAM field of the IPv6 compressed header as DAM=11. 528 CID and DAC MUST be set to CID=1 and DAC=1. If a context is defined 529 for the prefix of the IPv6 source address, the 6LBR MUST indicate 530 this context in the source fields of the compressed IPv6 header, and 531 MUST elide that prefix as well. For this, the 6LBR MUST set the SAM 532 field of the IPv6 compressed header as CID=1, SAC=1 and SAM=01 or 533 SAM=11. 535 3.3. Internet connectivity scenarios 537 In a typical scenario, the DECT ULE network is connected to the 538 Internet as shown in the Figure 5. 540 A degenerate scenario can be imagined where a PP is acting as 6LBR 541 and providing Internet connectivity for the FP. How the FP could 542 then further provide Internet connectivity to other PP, possibly 543 connected to the FP, is out of the scope of this document. 545 6LN 546 \ ____________ 547 \ / \ 548 6LN ---- 6LBR --- | Internet | 549 / \____________/ 550 / 551 6LN 553 <-- DECT ULE --> 555 Figure 5: DECT ULE network connected to the Internet 557 In some scenarios, the DECT ULE network may transiently or 558 permanently be an isolated network as shown in the Figure 6. 560 6LN 6LN 561 \ / 562 \ / 563 6LN --- 6LBR --- 6LN 564 / \ 565 / \ 566 6LN 6LN 568 <------ DECT ULE -----> 570 Figure 6: Isolated DECT ULE network 572 In the isolated network scenario, communications between 6LN and 6LBR 573 can use IPv6 link-local methodology, but for communications between 574 different PP, the FP has to act as 6LBR, number the network with ULA 575 prefix [RFC4193], and route packets between PP. 577 4. IANA Considerations 579 There are no IANA considerations related to this document. 581 5. Security Considerations 583 The secure transmission of speech over DECT will be based on the 584 DSAA2 and DSC2 work developed by the DF Security group / ETSI TC DECT 585 and the ETSI SAGE Security expert group. 587 DECT ULE communications are secured at the link-layer (DLC) by 588 encryption and per-message authentication through CCM mode (Counter 589 with CBC-MAC) similar to [RFC3610]. The underlying algorithm for 590 providing encryption and authentication is AES128. 592 The DECT ULE pairing procedure generates a master authentication key 593 (UAK) and during location registration procedure or when the 594 permanent virtual circuit are established, the session security keys 595 are generated. Session security keys may be renewed regularly. The 596 generated security keys (UAK and session security keys) are 597 individual for each FP-PP binding, hence all PP in a system have 598 different security keys. DECT ULE PPs do not use any shared 599 encryption key. 601 The IPv6 address configuration as described in Section 3.2.1 allows 602 implementations the choice to support [I-D.ietf-6man-default-iids] 603 for non-link addresses. 605 6. ETSI Considerations 607 ETSI is standardizing a list of known application layer protocols 608 that can use the DECT ULE permanent virtual circuit packet data 609 service. Each protocol is identified by a unique known identifier, 610 which is exchanged in the service-change procedure as defined in 611 [TS102.939-1]. The IPv6/6LoWPAN as described in this document is 612 considered as an application layer protocol on top of DECT ULE. In 613 order to provide interoperability between 6LoWPAN / DECT ULE devices 614 a common protocol identifier for 6LoWPAN is standardized by ETSI. 616 The ETSI DECT ULE Application Protocol Identifier is specified to 617 0x06 for 6LoWPAN. 619 7. Acknowledgements 621 We are grateful to the members of the IETF 6lo working group; this 622 document borrows liberally from their work. 624 Ralph Droms has provided valuable feedback for this draft. 626 8. References 628 8.1. Normative References 630 [EN300.175-part1-7] 631 ETSI, "Digital Enhanced Cordless Telecommunications 632 (DECT); Common Interface (CI);", August 2013. 634 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 635 Requirement Levels", BCP 14, RFC 2119, March 1997. 637 [RFC2464] Crawford, M., "Transmission of IPv6 Packets over Ethernet 638 Networks", RFC 2464, December 1998. 640 [RFC3610] Whiting, D., Housley, R., and N. Ferguson, "Counter with 641 CBC-MAC (CCM)", RFC 3610, September 2003. 643 [RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic 644 Host Configuration Protocol (DHCP) version 6", RFC 3633, 645 December 2003. 647 [RFC4193] Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast 648 Addresses", RFC 4193, October 2005. 650 [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing 651 Architecture", RFC 4291, February 2006. 653 [RFC4541] Christensen, M., Kimball, K., and F. Solensky, 654 "Considerations for Internet Group Management Protocol 655 (IGMP) and Multicast Listener Discovery (MLD) Snooping 656 Switches", RFC 4541, May 2006. 658 [RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, 659 "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, 660 September 2007. 662 [RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless 663 Address Autoconfiguration", RFC 4862, September 2007. 665 [RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy 666 Extensions for Stateless Address Autoconfiguration in 667 IPv6", RFC 4941, September 2007. 669 [RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler, 670 "Transmission of IPv6 Packets over IEEE 802.15.4 671 Networks", RFC 4944, September 2007. 673 [RFC6282] Hui, J. and P. Thubert, "Compression Format for IPv6 674 Datagrams over IEEE 802.15.4-Based Networks", RFC 6282, 675 September 2011. 677 [RFC6775] Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann, 678 "Neighbor Discovery Optimization for IPv6 over Low-Power 679 Wireless Personal Area Networks (6LoWPANs)", RFC 6775, 680 November 2012. 682 [TS102.939-1] 683 ETSI, "Digital Enhanced Cordless Telecommunications 684 (DECT); Ultra Low Energy (ULE); Machine to Machine 685 Communications; Part 1: Home Automation Network (phase 686 1)", April 2013. 688 8.2. Informative References 690 [I-D.ietf-6man-default-iids] 691 Gont, F., Cooper, A., Thaler, D., and W. Will, 692 "Recommendation on Stable IPv6 Interface Identifiers", 693 draft-ietf-6man-default-iids-02 (work in progress), 694 January 2015. 696 Authors' Addresses 698 Peter B. Mariager 699 RTX A/S 700 Stroemmen 6 701 DK-9400 Noerresundby 702 Denmark 704 Email: pm@rtx.dk 706 Jens Toftgaard Petersen (editor) 707 RTX A/S 708 Stroemmen 6 709 DK-9400 Noerresundby 710 Denmark 712 Email: jtp@rtx.dk 714 Zach Shelby 715 Sensinode 716 150 Rose Orchard 717 San Jose, CA 95134 718 USA 720 Email: zach.shelby@arm.com 722 Marco van de Logt 723 Gigaset Communications GmbH 724 Frankenstrasse 2 725 D-46395 Bocholt 726 Germany 728 Email: marco.van-de-logt@gigaset.com 730 Dominique Barthel 731 Orange Labs 733 Email: dominique.barthel@orange.com