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Checking references for intended status: Informational ---------------------------------------------------------------------------- -- Looks like a reference, but probably isn't: 'TBD' on line 489 -- Looks like a reference, but probably isn't: 'RFC6775' on line 394 == Unused Reference: '9' is defined on line 524, but no explicit reference was found in the text == Unused Reference: '10' is defined on line 530, but no explicit reference was found in the text ** Obsolete normative reference: RFC 3633 (ref. '8') (Obsoleted by RFC 8415) Summary: 1 error (**), 0 flaws (~~), 3 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 6Lo Working Group Y. Hong 3 Internet-Draft Y. Choi 4 Intended status: Informational ETRI 5 Expires: January 5, 2015 J. Youn 6 DONG-EUI Univ 7 D. Kim 8 KNU 9 JH. Choi 10 Samsung Electronics Co., 11 July 4, 2014 13 Transmission of IPv6 Packets over Near Field Communication 14 draft-hong-6lo-ipv6-over-nfc-00.txt 16 Abstract 18 Near field communication (NFC) is a set of standards for smartphones 19 and similar devices to establish radio communication with each other 20 by touching them together or bringing them into proximity, usually no 21 more than a few inches. NFC standards cover communications protocols 22 and data exchange formats, and are based on existing radio-frequency 23 identification (RFID) standards including ISO/IEC 14443 and FeliCa. 24 The standards include ISO/IEC 18092 and those defined by the NFC 25 Forum, which was founded in 2004 by Nokia, Philips Semiconductors. 26 The NFC technology has been widely implemented and available in 27 mobile phones, laptop computers, and many other devices. This 28 document describes how IPv6 is transforted over NFC using 6LowPAN 29 techiques. 31 Status of This Memo 33 This Internet-Draft is submitted in full conformance with the 34 provisions of BCP 78 and BCP 79. 36 Internet-Drafts are working documents of the Internet Engineering 37 Task Force (IETF). Note that other groups may also distribute 38 working documents as Internet-Drafts. The list of current Internet- 39 Drafts is at http://datatracker.ietf.org/drafts/current/. 41 Internet-Drafts are draft documents valid for a maximum of six months 42 and may be updated, replaced, or obsoleted by other documents at any 43 time. It is inappropriate to use Internet-Drafts as reference 44 material or to cite them other than as "work in progress." 46 This Internet-Draft will expire on January 5, 2015. 48 Copyright Notice 50 Copyright (c) 2014 IETF Trust and the persons identified as the 51 document authors. All rights reserved. 53 This document is subject to BCP 78 and the IETF Trust's Legal 54 Provisions Relating to IETF Documents 55 (http://trustee.ietf.org/license-info) in effect on the date of 56 publication of this document. Please review these documents 57 carefully, as they describe your rights and restrictions with respect 58 to this document. Code Components extracted from this document must 59 include Simplified BSD License text as described in Section 4.e of 60 the Trust Legal Provisions and are provided without warranty as 61 described in the Simplified BSD License. 63 Table of Contents 65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 66 2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4 67 3. Overview of Near Field Communication technology . . . . . . . 4 68 3.1. Peer-to-peer Mode for IPv6 over NFC . . . . . . . . . . . 4 69 3.2. Protocol Stacks in IPv6 over NFC . . . . . . . . . . . . 4 70 3.3. NFC-enabled device addressing . . . . . . . . . . . . . . 5 71 3.4. NFC packet size and MTU . . . . . . . . . . . . . . . . . 6 72 4. Specification of IPv6 over NFC . . . . . . . . . . . . . . . 6 73 4.1. Protocol Stack . . . . . . . . . . . . . . . . . . . . . 7 74 4.2. Link Model . . . . . . . . . . . . . . . . . . . . . . . 7 75 4.3. Stateless adress autoconfiguration . . . . . . . . . . . 8 76 4.4. Neighbor discovery . . . . . . . . . . . . . . . . . . . 8 77 4.5. Header compression . . . . . . . . . . . . . . . . . . . 9 78 4.6. Fragmentation and Reassembly . . . . . . . . . . . . . . 9 79 4.7. Unicast and Multicast address Mapping . . . . . . . . . . 9 80 5. Internet connectivity scenarios . . . . . . . . . . . . . . . 9 81 5.1. NFC-enabled device connected to the Internet . . . . . . 10 82 5.2. Isolated NFC-enabled device network . . . . . . . . . . . 10 83 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 84 7. Security Considerations . . . . . . . . . . . . . . . . . . . 11 85 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 86 8.1. Normative References . . . . . . . . . . . . . . . . . . 11 87 8.2. Informative References . . . . . . . . . . . . . . . . . 12 88 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 90 1. Introduction 92 NFC is a set of short-range wireless technologies, typically 93 requiring a distance of 10 cm or less. NFC operates at 13.56 MHz on 94 ISO/IEC 18000-3 air interface and at rates ranging from 106 kbit/s to 95 424 kbit/s. NFC always involves an initiator and a target; the 96 initiator actively generates an RF field that can power a passive 97 target. This enables NFC targets to take very simple form factors 98 such as tags, stickers, key fobs, or cards that do not require 99 batteries. NFC peer-to-peer communication is possible, provided both 100 devices are powered. NFC builds upon RFID systems by allowing two- 101 way communication between endpoints, where earlier systems such as 102 contactless smart cards were one-way only. It has been used in 103 devices such as mobile phones, running Android operating system, 104 named with a feature called "Android Beam". In addition, it is 105 expected for the other mobile phones, running the other operating 106 systems (e.g., iOS, etc.) to be equipped with NFC technology in the 107 near future. 109 Considering the potential for exponential growth in the number of 110 heterogeneous air interface technologies, NFC would be widely used as 111 one of the other air interface technologies, such as Bluetooth Low 112 Energy (BT-LE), WiFi, and so on. Each of the heterogeneous air 113 interface technologies has its own characteristics, which cannot be 114 covered by the other technologies, so various kinds of aire interface 115 technologies would be existing together. therefore, it is required 116 for them to communicate each other. NFC also has the strongest point 117 (e.g., secure communication distance of 10 cm) to prevent the third 118 party from attacking privacy. 120 When the number of devices and things having different air interface 121 technologies communicate each other, IPv6 is an ideal internet 122 protocols owing to its large address space. Also, NFC would be one 123 of the endpoints using IPV6. Therefore, This document describes how 124 IPv6 is transforted over NFC using 6LoWPAN techiques with following 125 scopes. 127 o Overview of NFC technologies; 129 o Specifications for IPv6 over NFC; 131 * Neighbor Discovery; 133 * Addressing and Configuration; 135 * Header Compression; 137 * Fragmentation for a IPv6 datagram; 139 RFC4944 [1] specifies the transmission of IPv6 over IEEE 802.15.4. 140 The NFC link also has similar characteristics to that of IEEE 141 802.15.4. Many of the mechanisms defined in the RFC4944 [1] can be 142 applied to the transmission of IPv6 on NFC links. This document 143 specifies the details of IPv6 transmission over NFC links. 145 2. Conventions and Terminology 147 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 148 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 149 document are to be interpreted as described in [2]. 151 3. Overview of Near Field Communication technology 153 NFC technology enables simple and safe two-way interactions between 154 electronic devices, allowing consumers to perform contactless 155 transactions, access digital content, and connect electronic devices 156 with a single touch. NFC complements many popular consumer level 157 wireless technologies, by utilizing the key elements in existing 158 standards for contactless card technology (ISO/IEC 14443 A&B and 159 JIS-X 6319-4). NFC can be compatible with existing contactless card 160 infrastructure and it enables a consumer to utilize one device across 161 different systems. 163 Extending the capability of contactless card technology, NFC also 164 enables devices to share information at a distance that is less than 165 4 centimeters with a maximum communication speed of 424 kbps. Users 166 can share business cards, make transactions, access information from 167 a smart poster or provide credentials for access control systems with 168 a simple touch. 170 NFC's bidirectional communication ability is ideal for establishing 171 connections with other technologies by the simplicity of touch. In 172 addition to the easy connection and quick transactions, simple data 173 sharing is also available. 175 3.1. Peer-to-peer Mode for IPv6 over NFC 177 NFC-enabled devices are unique in that they can support three modes 178 of operation: card emulation, peer-to-peer, and reader/writer. Peer- 179 to-peer mode enables two NFC-enabled devices to communicate with each 180 other to exchange information and share files, so that users of NFC- 181 enabled devices can quickly share contact information and other files 182 with a touch. Therefore, a NFC-enabled device can securely send IPv6 183 packets to any corresponding node on the Internet when a NFC-enabled 184 gateway is linked to the Internet. 186 3.2. Protocol Stacks in IPv6 over NFC 188 The IP protocol can use the services provided by Logical Link Control 189 Protocol (LLCP) in the NFC stack to provide reliable, two-way 190 transport of information between the peer devices. Figure 1 depicts 191 the NFC P2P protocol stack with IPv6 bindings to the LLCP. 193 For data communication in IPv6 over NFC, an IPv6 packet SHALL be 194 received at LLCP of NFC and transported to an Information Field in 195 Protocol Data Unit (I PDU) of LLCP of the NFC-enabled peer device. 196 Since LLCP does not support fragmentation and reassembly, Upper 197 Layers SHOULD support fragmentation and reassembly. For IPv6 198 addressing or address configuration, LLCP SHALL provide related 199 information, such as link layer addresses, to its upper layer. LLCP 200 to IPv6 protocol Binding SHALL transfer the SSAP and DSAP value to 201 the IPv6 over NFC protocol. SSAP stands for Source Service Access 202 Point, which is 6-bit value meaning a kind of LLC address, while DSAP 203 means a Logical Link Control (LLC) address of destination NFC-enabled 204 device. 206 | | 207 | | Application Layer 208 | Upper Layer Protocols | Transport Layer 209 | | Network Layer 210 | | | 211 +----------------------------------------+ <------------------ 212 | IPv6-LLCP Binding | | 213 +----------------------------------------+ NFC 214 | | Logical Link 215 | Logical Link Control Protocol | Layer 216 | (LLCP) | | 217 +----------------------------------------+ <------------------ 218 | | | 219 | Activities | | 220 | Digital Protocol | NFC 221 | | Physical 222 +----------------------------------------+ Layer 223 | | | 224 | RF Analog | | 225 | | | 226 +----------------------------------------+ <------------------ 228 Figure 1: Protocol Stack of NFC 230 3.3. NFC-enabled device addressing 232 NFC-enabled devices are identified by 6-bit LLC address. In other 233 words, Any address SHALL be usable as both an SSAP and a DSAP 234 address. According to NFCForum-TS-LLCP_1.1 [3], address values 235 between 0 and 31 (00h - 1Fh) SHALL be reserved for well-known service 236 access points for Service Discovery Protocol (SDP). Address values 237 between 32 and 63 (20h - 3Fh) inclusively, SHALL be assigned by the 238 local LLC as the result of an upper layer service request. 240 3.4. NFC packet size and MTU 242 As mentioned in Section 3.2, an IPv6 packet SHALL be received at LLCP 243 of NFC and transported to an Information Field in Protocol Data Unit 244 (I PDU) of LLCP of the NFC-enabled peer device. The format of the I 245 PDU SHALL be as shown in Figure 2. 247 0 0 1 1 2 2 248 0 6 0 6 0 4 249 +------+----+------+----+----+---------------------------------+ 250 |DDDDDD|1100|SSSSSS|N(S)|N(R)| Service Data Unit | 251 +------+----+------+----+----+---------------------------------+ 252 | <------- 3 bytes --------> | | 253 | <------------------- 128 bytes (default) ------------------> | 254 | | 256 Figure 2: Format of the I PDU in NFC 258 The I PDU sequence field SHALL contain two sequence numbers: The send 259 sequence number N(S) and the receive sequence number N(R). The send 260 sequence number N(S) SHALL indicate the sequence number associated 261 with this I PDU. The receive sequence number N(R) value SHALL 262 indicate that I PDUs numbered up through N(R) - 1 have been received 263 correctly by the sender of this I PDU and successfully passed to the 264 senders SAP identified in the SSAP field. These I PDUs SHALL be 265 considered as acknowledged. 267 The information field of an I PDU SHALL contain a single service data 268 unit. The maximum number of octets in the information field SHALL be 269 determined by the Maximum Information Unit (MIU) for the data link 270 connection. The default value of the MIU for I PDUs SHALL be 128 271 octets. The local and remote LLCs each establish and maintain 272 distinct MIU values for each data link connection endpoint. Also, An 273 LLC MAY announce a larger MIU for a data link connection by 274 transmitting an MIUX extension parameter within the information 275 field. 277 4. Specification of IPv6 over NFC 279 NFC technology sets also has considerations and requirements owing to 280 low power consumption and allowed protocol overhead. 6LoWPAN 281 standards RFC4944 [1], RFC6775 [4], and RFC6282 [5] provide useful 282 functionality for reducing overhead which can be applied to BT-LE. 283 This functionality comprises of link-local IPv6 addresses and 284 stateless IPv6 address auto-configuration (see Section 4.3), Neighbor 285 Discovery (see Section 3.2.2) and header compression (see 286 Section 3.2.3). 288 One of the differences between IEEE 802.15.4 and NFC is that the 289 former supports both star and mesh topology (and requires a routing 290 protocol), whereas NFC can support direct peer-to-peer connection and 291 simple mech-like topology depending on NFC application scenarios 292 because of very short RF distance of 10 cm or less. 294 4.1. Protocol Stack 296 Figure 3 illustrates IPv6 over NFC. Upper layer protocols can be 297 transport protocols (TCP and UDP), application layer, and the others 298 capable running on the top of IPv6. 300 | | Transport & 301 | Upper Layer Protocols | Application Layer 302 +----------------------------------------+ <------------------ 303 | | | 304 | IPv6 | | 305 | | Network 306 +----------------------------------------+ Layer 307 | Adaptation Layer for IPv6 over NFC | | 308 +----------------------------------------+ <------------------ 309 | IPv6-LLCP Binding | 310 | Logical Link Control Protocol | NFC Link Layer 311 | (LLCP) | | 312 +----------------------------------------+ <------------------ 313 | | | 314 | Activities | NFC 315 | Digital Protocol | Physical Layer 316 | RF Analog | | 317 | | | 318 +----------------------------------------+ <------------------ 320 Figure 3: Protocol Stack for IPv6 over NFC 322 Adaptation layer for IPv6 over NFC SHALL support neighbor discovery, 323 address auto-configuration, header compression, and fragmentation. 325 [TBD] 327 4.2. Link Model 329 In the case of BT-LE, L2CAP supports fragmentation and reassembly 330 (FAR) functionality; therefore, adaptation layer for IPv6 over BT-LE 331 do not have to conduct the FAR procedure. However, NFC link layer is 332 similar to IEEE 802.15.4. Adaptation layer for IPv6 over NFC SHOULD 333 support FAR functionality. Therefore, fragmentation functionality as 334 defined in RFC4944 [1] SHALL be used in NFC-enabled device networks. 336 The NFC link between two communicating devices is considered to be a 337 point-to-point link only. Unlike in BT-LE, NFC link does not 338 consider star topology and mesh network topology but peer-to-peer 339 topology and simple multi-hop topology. Due to this characteristics, 340 6LoWPAN functionality, such as addressing and auto-configuration, and 341 header compression, is specialized into NFC. 343 [TBD] 345 4.3. Stateless adress autoconfiguration 347 A NFC-enabled device (i.e., 6LN) performs stateless address 348 autoconfiguration as per RFC4862 [6]. A 64-bit Interface identifier 349 (IID) for a NFC interface MAY be formed by utilizing the 6-bit NFC 350 LLCP address (i.e., SSAP or DSAP) (see Section 3.3). In the case of 351 NFC-enabled device address, the "Universal/Local" bit MUST be set to 352 0 RFC4291 [7]. Only if the NFC-enabled device address is known to be 353 a public address the "Universal/Local" bit can be set to 1. As 354 defined in RFC 4291, the IPv6 link-local address for a NFC-enabled 355 device is formed by appending the IID, to the prefix FE80::/64, as 356 depicted in Figure 4. 358 0 0 0 1 1 359 0 1 6 2 2 360 0 0 4 2 7 361 +----------+------------------+---------------------+------+ 362 |1111111010| zeros | zeros | SSAP | 363 +----------+------------------+---------------------+------+ 364 | | 365 | <---------------------- 128 bits ----------------------> | 366 | | 368 Figure 4: IPv6 link-local address in NFC 370 The tool for a 6LBR to obtain an IPv6 prefix for numbering the NFC 371 network is can be accomplished via DHCPv6 Prefix Delegation RFC3633 372 [8]. 374 [TBD] 376 4.4. Neighbor discovery 378 Neighbor Discovery Optimization for 6LoWPANs [RFC6775] [4] describes 379 the neighbor discovery approach in several 6LoWPAN topologies, such 380 as mesh topology. NFC does not consider complicated mesh topology 381 but simple multi-hop network topology or directly connected peer-to- 382 peer network. Therefore, the following aspects of the Neighbor 383 Discovery optimizations [RFC6775] are applicable to NFC: 385 1. In a case that a NFC-enabled device (6LN) is directly connected 386 to 6LBR, A NFC 6LN MUST register its address with the 6LBR by 387 sending a Neighbor Solicitation (NS) message with the ARO option 388 and process the Neighbor Advertisement (NA) accordingly. In 389 addition, DHCPv6 is used to assigned an address, Duplicate 390 Address Detection (DAD) is not required. 392 2. For sending Router Solicitations and processing Router 393 Advertisements the NFC 6LNs MUST follow Sections 5.3 and 5.4 of 394 the [RFC6775]. 396 [TBD] 398 4.5. Header compression 400 Header compression as defined in RFC 6282 [5] , which specifies the 401 compression format for IPv6 datagrams on top of IEEE 802.15.4, is 402 REQUIRED in this document as the basis for IPv6 header compression on 403 top of NFC. All headers MUST be compressed according to RFC 6282 404 encoding formats. 406 [TBD] 408 4.6. Fragmentation and Reassembly 410 Fragmentation and reassembly (FAR) as defined in RFC 4944, which 411 specifies the fragmentation methods for IPv6 datagrams on top of IEEE 412 802.15.4, is REQUIRED in this document as the basis for IPv6 datagram 413 FAR on top of NFC. All headers MUST be compressed according to RFC 414 4944 encoding formats, but the default MTU of NFC is 128 bytes. This 415 MUST be considered. 417 [TBD] 419 4.7. Unicast and Multicast address Mapping 421 [TBD] 423 5. Internet connectivity scenarios 425 As two typical scenarios, the NFC network can be isolated and 426 connected to the Internet. 428 [TBD] 430 5.1. NFC-enabled device connected to the Internet 432 One of the key applications by using adaptation technology of IPv6 433 over NFC is the most securely transmitting IPv6 packets because RF 434 distance between 6LN and 6LBR SHOULD be within 10 cm. If any third 435 party wants to hack into the RF between them, it MUST come to nearly 436 touch them. Applications can choose which kinds of air interfaces 437 (e.g., Bluetooth LE, WiFi, NFC, etc.) to send data depending 438 characteristics of data. NFC SHALL be the best solution for secured 439 and private information. 441 Figure 5 illustrates an example of NFC-enabled device network 442 connected to the Internet. Distance between 6LN and 6LBR SHOULD be 443 10 cm or less. If there is any of close laptop computers to a user, 444 it SHALL becomes the 6LBR. Additionally, When the user mounts a NFC- 445 enabled air interface adapter (e.g., portable small NFC dongle) on 446 the close laptop PC, the user's NFC-enabled device (6LN) can 447 communicate the laptop PC (6LBR) within 10 cm distance. 449 ************ 450 6LN ------------------- 6LBR -----* Internet *------- CN 451 | (dis. 10 cm or less) | ************ | 452 | | | 453 | <-------- NFC -------> | <----- IPv6 packet ------> | 454 | (IPv6 over NFC packet) | | 456 Figure 5: NFC-enabled device network connected to the Internet 458 [TBD] 460 5.2. Isolated NFC-enabled device network 462 In some scenarios, the NFC-enabled device network may transiently be 463 a simple isolated network as shown in the Figure 6. 465 6LN ---------------------- 6LR ---------------------- 6LN 466 | (10 cm or less) | (10 cm or less) | 467 | | | 468 | <--------- NFC --------> | <--------- NFC --------> | 469 | (IPv6 over NFC packet) | (IPv6 over NFC packet) | 471 Figure 6: Isolated NFC-enabled device network 473 In mobile phone markets, applications are designed and made by user 474 developers. They may image interesting applications, where three or 475 more mobile phones touch or attach each other to accomplish 476 outstanding performance. For instance, three or more mobile phones 477 can play multi-channel sound of music together. In addition, 478 attached three or more mobile phones can make an extended banner to 479 show longer sentences in a concert hall. 481 [TBD] 483 6. IANA Considerations 485 [TBD] 487 7. Security Considerations 489 [TBD] 491 8. References 493 8.1. Normative References 495 [1] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler, 496 "Transmission of IPv6 Packets over IEEE 802.15.4 497 Networks", RFC 4944, September 2007. 499 [2] Bradner, S., "Key words for use in RFCs to Indicate 500 Requirement Levels", BCP 14, RFC 2119, March 1997. 502 [3] "Logical Link Control Protocol version 1.1", NFC Forum 503 Technical Specification , June 2011. 505 [4] Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann, 506 "Neighbor Discovery Optimization for IPv6 over Low-Power 507 Wireless Personal Area Networks (6LoWPANs)", RFC 6775, 508 November 2012. 510 [5] Hui, J. and P. Thubert, "Compression Format for IPv6 511 Datagrams over IEEE 802.15.4-Based Networks", RFC 6282, 512 September 2011. 514 [6] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless 515 Address Autoconfiguration", RFC 4862, September 2007. 517 [7] Hinden, R. and S. Deering, "IP Version 6 Addressing 518 Architecture", RFC 4291, February 2006. 520 [8] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic 521 Host Configuration Protocol (DHCP) version 6", RFC 3633, 522 December 2003. 524 [9] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, 525 "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, 526 September 2007. 528 8.2. Informative References 530 [10] "Near Field Communication - Interface and Protocol (NFCIP- 531 1) 3rd Ed.", ECMA-340 , June 2013. 533 Authors' Addresses 535 Yong-Geun Hong 536 ETRI 537 161 Gajeong-Dong Yuseung-Gu 538 Daejeon 305-700 539 Korea 541 Phone: +82 42 860 6557 542 Email: yghong@etri.re.kr 544 Younghwan Choi 545 ETRI 546 218 Gajeongno, Yuseong 547 Daejeon 305-700 548 Korea 550 Phone: +82 42 860 1429 551 Email: yhc@etri.re.kr 553 Joo-Sang Youn 554 DONG-EUI University 555 176 Eomgwangno Busan_jin_gu 556 Busan 614-714 557 Korea 559 Phone: +82 51 890 1993 560 Email: joosang.youn@gmail.com 561 Dongkyun Kim 562 Kyungpook National University 563 80 Daehak-ro, Buk-gu 564 Daegu 702-701 565 Korea 567 Phone: +82 53 950 7571 568 Email: dongkyun@knu.ac.kr 570 JinHyouk Choi 571 Samsung Electronics Co., 572 129 Samsung-ro, Youngdong-gu 573 Suwon 447-712 574 Korea 576 Phone: +82 2 2254 0114 577 Email: jinchoe@samsung.com