idnits 2.17.1 draft-ietf-6lo-nfc-01.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 exact meaning of the all-uppercase expression 'NOT REQUIRED' is not defined in RFC 2119. If it is intended as a requirements expression, it should be rewritten using one of the combinations defined in RFC 2119; otherwise it should not be all-uppercase. == Using lowercase 'not' together with uppercase 'MUST', 'SHALL', 'SHOULD', or 'RECOMMENDED' is not an accepted usage according to RFC 2119. Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'MUST not' in this paragraph: All IPv6 multicast packets MUST be sent to NFC Destination Address, 0x3F (broadcast) and filtered at the IPv6 layer. When represented as a 16-bit address in a compressed header, it MUST be formed by padding on the left with a zero. In addition, the NFC Destination Address, 0x3F, MUST not be used as a unicast NFC address of SSAP or DSAP. -- The document date (July 5, 2015) is 3211 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) == Unused Reference: '11' is defined on line 676, but no explicit reference was found in the text -- Possible downref: Non-RFC (?) normative reference: ref. '3' ** 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-G. Hong 3 Internet-Draft Y-H. Choi 4 Intended status: Standards Track ETRI 5 Expires: January 6, 2016 J-S. Youn 6 DONG-EUI Univ 7 D-K. Kim 8 KNU 9 J-H. Choi 10 Samsung Electronics Co., 11 July 5, 2015 13 Transmission of IPv6 Packets over Near Field Communication 14 draft-ietf-6lo-nfc-01 16 Abstract 18 Near field communication (NFC) is a set of standards for smartphones 19 and portable devices to establish radio communication with each other 20 by touching them together or bringing them into proximity, usually no 21 more than 10 cm. NFC standards cover communications protocols and 22 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. The NFC technology has been widely implemented and available 26 in mobile phones, laptop computers, and many other devices. This 27 document describes how IPv6 is transmitted over NFC using 6LowPAN 28 techniques. 30 Status of This Memo 32 This Internet-Draft is submitted in full conformance with the 33 provisions of BCP 78 and BCP 79. 35 Internet-Drafts are working documents of the Internet Engineering 36 Task Force (IETF). Note that other groups may also distribute 37 working documents as Internet-Drafts. The list of current Internet- 38 Drafts is at http://datatracker.ietf.org/drafts/current/. 40 Internet-Drafts are draft documents valid for a maximum of six months 41 and may be updated, replaced, or obsoleted by other documents at any 42 time. It is inappropriate to use Internet-Drafts as reference 43 material or to cite them other than as "work in progress." 45 This Internet-Draft will expire on January 6, 2016. 47 Copyright Notice 49 Copyright (c) 2015 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 respect 57 to this document. Code Components extracted from this document must 58 include Simplified BSD License text as described in Section 4.e of 59 the Trust Legal Provisions and are provided without warranty as 60 described in the Simplified BSD License. 62 Table of Contents 64 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 65 2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4 66 3. Overview of Near Field Communication Technology . . . . . . . 4 67 3.1. Peer-to-peer Mode of NFC . . . . . . . . . . . . . . . . 4 68 3.2. Protocol Stacks of NFC . . . . . . . . . . . . . . . . . 5 69 3.3. NFC-enabled Device Addressing . . . . . . . . . . . . . . 6 70 3.4. NFC MAC PDU Size and MTU . . . . . . . . . . . . . . . . 6 71 4. Specification of IPv6 over NFC . . . . . . . . . . . . . . . 8 72 4.1. Protocol Stacks . . . . . . . . . . . . . . . . . . . . . 8 73 4.2. Link Model . . . . . . . . . . . . . . . . . . . . . . . 9 74 4.3. Stateless Address Autoconfiguration . . . . . . . . . . . 10 75 4.4. IPv6 Link Local Address . . . . . . . . . . . . . . . . . 10 76 4.5. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 11 77 4.6. Header Compression . . . . . . . . . . . . . . . . . . . 11 78 4.7. Fragmentation and Reassembly . . . . . . . . . . . . . . 12 79 4.8. Unicast Address Mapping . . . . . . . . . . . . . . . . . 12 80 4.9. Multicast Address Mapping . . . . . . . . . . . . . . . . 13 81 5. Internet Connectivity Scenarios . . . . . . . . . . . . . . . 13 82 5.1. NFC-enabled Device Connected to the Internet . . . . . . 13 83 5.2. Isolated NFC-enabled Device Network . . . . . . . . . . . 14 84 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 85 7. Security Considerations . . . . . . . . . . . . . . . . . . . 14 86 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14 87 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 88 9.1. Normative References . . . . . . . . . . . . . . . . . . 15 89 9.2. Informative References . . . . . . . . . . . . . . . . . 15 90 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 92 1. Introduction 94 NFC is a set of short-range wireless technologies, typically 95 requiring a distance of 10 cm or less. NFC operates at 13.56 MHz on 96 ISO/IEC 18000-3 air interface and at rates ranging from 106 kbit/s to 97 424 kbit/s. NFC always involves an initiator and a target; the 98 initiator actively generates an RF field that can power a passive 99 target. This enables NFC targets to take very simple form factors 100 such as tags, stickers, key fobs, or cards that do not require 101 batteries. NFC peer-to-peer communication is possible, provided both 102 devices are powered. NFC builds upon RFID systems by allowing two- 103 way communication between endpoints, where earlier systems such as 104 contactless smart cards were one-way only. It has been used in 105 devices such as mobile phones, running Android operating system, 106 named with a feature called "Android Beam". In addition, it is 107 expected for the other mobile phones, running the other operating 108 systems (e.g., iOS, etc.) to be equipped with NFC technology in the 109 near future. 111 Considering the potential for exponential growth in the number of 112 heterogeneous air interface technologies, NFC would be widely used as 113 one of the other air interface technologies, such as Bluetooth Low 114 Energy (BT-LE), Wi-Fi, and so on. Each of the heterogeneous air 115 interface technologies has its own characteristics, which cannot be 116 covered by the other technologies, so various kinds of air interface 117 technologies would be existing together. Therefore, it is required 118 for them to communicate each other. NFC also has the strongest point 119 (e.g., secure communication distance of 10 cm) to prevent the third 120 party from attacking privacy. 122 When the number of devices and things having different air interface 123 technologies communicate each other, IPv6 is an ideal internet 124 protocols owing to its large address space. Also, NFC would be one 125 of the endpoints using IPv6. Therefore, This document describes how 126 IPv6 is transmitted over NFC using 6LoWPAN techiques with following 127 scopes. 129 o Overview of NFC technologies; 131 o Specifications for IPv6 over NFC; 133 * Neighbor Discovery; 135 * Addressing and Configuration; 137 * Header Compression; 139 * Fragmentation & Reassembly for a IPv6 datagram; 141 RFC4944 [1] specifies the transmission of IPv6 over IEEE 802.15.4. 142 The NFC link also has similar characteristics to that of IEEE 143 802.15.4. Many of the mechanisms defined in the RFC4944 [1] can be 144 applied to the transmission of IPv6 on NFC links. This document 145 specifies the details of IPv6 transmission over NFC links. 147 2. Conventions and Terminology 149 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 150 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 151 document are to be interpreted as described in [2]. 153 3. Overview of Near Field Communication Technology 155 NFC technology enables simple and safe two-way interactions between 156 electronic devices, allowing consumers to perform contactless 157 transactions, access digital content, and connect electronic devices 158 with a single touch. NFC complements many popular consumer level 159 wireless technologies, by utilizing the key elements in existing 160 standards for contactless card technology (ISO/IEC 14443 A&B and 161 JIS-X 6319-4). NFC can be compatible with existing contactless card 162 infrastructure and it enables a consumer to utilize one device across 163 different systems. 165 Extending the capability of contactless card technology, NFC also 166 enables devices to share information at a distance that is less than 167 10 cm with a maximum communication speed of 424 kbps. Users can 168 share business cards, make transactions, access information from a 169 smart poster or provide credentials for access control systems with a 170 simple touch. 172 NFC's bidirectional communication ability is ideal for establishing 173 connections with other technologies by the simplicity of touch. In 174 addition to the easy connection and quick transactions, simple data 175 sharing is also available. 177 3.1. Peer-to-peer Mode of NFC 179 NFC-enabled devices are unique in that they can support three modes 180 of operation: card emulation, peer-to-peer, and reader/writer. Peer- 181 to-peer mode enables two NFC-enabled devices to communicate with each 182 other to exchange information and share files, so that users of NFC- 183 enabled devices can quickly share contact information and other files 184 with a touch. Therefore, a NFC-enabled device can securely send IPv6 185 packets to any corresponding node on the Internet when a NFC-enabled 186 gateway is linked to the Internet. 188 3.2. Protocol Stacks of NFC 190 The IP protocol can use the services provided by Logical Link Control 191 Protocol (LLCP) in the NFC stack to provide reliable, two-way 192 transport of information between the peer devices. Figure 1 depicts 193 the NFC P2P protocol stack with IPv6 bindings to the LLCP. 195 For data communication in IPv6 over NFC, an IPv6 packet SHALL be 196 received at LLCP of NFC and transported to an Information Field in 197 Protocol Data Unit (I PDU) of LLCP of the NFC-enabled peer device. 198 Since LLCP does not support fragmentation and reassembly, upper 199 layers SHOULD support fragmentation and reassembly. For IPv6 200 addressing or address configuration, LLCP SHALL provide related 201 information, such as link layer addresses, to its upper layer. LLCP 202 to IPv6 protocol Binding SHALL transfer the SSAP and DSAP value to 203 the IPv6 over NFC protocol. SSAP stands for Source Service Access 204 Point, which is 6-bit value meaning a kind of Logical Link Control 205 (LLC) address, while DSAP means a LLC address of destination NFC- 206 enabled device. 208 | | 209 | | Application Layer 210 | Upper Layer Protocols | Transport Layer 211 | | Network Layer 212 | | | 213 +----------------------------------------+ <------------------ 214 | IPv6-LLCP Binding | | 215 +----------------------------------------+ NFC 216 | | Logical Link 217 | Logical Link Control Protocol | Layer 218 | (LLCP) | | 219 +----------------------------------------+ <------------------ 220 | | | 221 | Activities | | 222 | Digital Protocol | NFC 223 | | Physical 224 +----------------------------------------+ Layer 225 | | | 226 | RF Analog | | 227 | | | 228 +----------------------------------------+ <------------------ 230 Figure 1: Protocol Stacks of NFC 232 The LLCP consists of Logical Link Control (LLC) and MAC Mapping. The 233 MAC Mapping integrates an existing RF protocol into the LLCP 234 architecture. The LLC contains three components, such as Link 235 Management, Connection-oriented Transport, and Connection-less 236 Transport. The Link Management component is responsible for 237 serializing all connection-oriented and connectionless LLC PDU 238 (Protocol Data Unit) exchanges and for aggregation and disaggregation 239 of small PDUs. This component also guarantees asynchronous balanced 240 mode communication and provides link status supervision by performing 241 the symmetry procedure. The Connection-oriented Transport component 242 is responsible for maintaining all connection-oriented data exchanges 243 including connection set-up and termination. The Connectionless 244 Transport component is responsible for handling unacknowledged data 245 exchanges. 247 3.3. NFC-enabled Device Addressing 249 NFC-enabled devices are identified by 6-bit LLC address. In other 250 words, Any address SHALL be usable as both an SSAP and a DSAP 251 address. According to NFCForum-TS-LLCP_1.1 [3], address values 252 between 0 and 31 (00h - 1Fh) SHALL be reserved for well-known service 253 access points for Service Discovery Protocol (SDP). Address values 254 between 32 and 63 (20h - 3Fh) inclusively, SHALL be assigned by the 255 local LLC as the result of an upper layer service request. 257 3.4. NFC MAC PDU Size and MTU 259 As mentioned in Section 3.2, an IPv6 packet SHALL be received at LLCP 260 of NFC and transported to an Unnumbered Information Protocol Data 261 Unit (UI PDU) and an Information Field in Protocol Data Unit (I PDU) 262 of LLCP of the NFC-enabled peer device. The format of the UI PDU and 263 I PDU SHALL be as shown in Figure 2 and Figure 3. 265 0 0 1 1 266 0 6 0 6 267 +------+----+------+-------------------------------------------+ 268 |DDDDDD|1100|SSSSSS| Service Data Unit | 269 +------+----+------+-------------------------------------------+ 270 | <-- 2 bytes ---> | | 271 | <------------------- 128 ~ 2176 bytes ---------------------> | 272 | | 274 Figure 2: Format of the UI PDU in NFC 276 0 0 1 1 2 2 277 0 6 0 6 0 4 278 +------+----+------+----+----+---------------------------------+ 279 |DDDDDD|1100|SSSSSS|N(S)|N(R)| Service Data Unit | 280 +------+----+------+----+----+---------------------------------+ 281 | <------- 3 bytes --------> | | 282 | <------------------- 128 ~ 2176 bytes ---------------------> | 283 | | 285 Figure 3: Format of the I PDU in NFC 287 The I PDU sequence field SHALL contain two sequence numbers: The send 288 sequence number N(S) and the receive sequence number N(R). The send 289 sequence number N(S) SHALL indicate the sequence number associated 290 with this I PDU. The receive sequence number N(R) value SHALL 291 indicate that I PDUs numbered up through N(R) - 1 have been received 292 correctly by the sender of this I PDU and successfully passed to the 293 senders SAP identified in the SSAP field. These I PDUs SHALL be 294 considered as acknowledged. 296 The information field of an I PDU SHALL contain a single service data 297 unit. The maximum number of octets in the information field SHALL be 298 determined by the Maximum Information Unit (MIU) for the data link 299 connection. The default value of the MIU for I PDUs SHALL be 128 300 octets. The local and remote LLCs each establish and maintain 301 distinct MIU values for each data link connection endpoint. Also, An 302 LLC MAY announce a larger MIU for a data link connection by 303 transmitting an MIUX extension parameter within the information 304 field. If no MIUX parameter is transmitted, the default MIU value of 305 128 SHALL be used. Otherwise, the MTU size in NFC LLCP SHALL 306 calculate the MIU value as follows: 308 MIU = 128 + MIUX. 310 According to NFCForum-TS-LLCP_1.1 [3], format of the MIUX parameter 311 TLV is as shown in Figure 4. 313 0 0 1 2 3 314 0 8 6 2 1 315 +--------+--------+----------------+ 316 | Type | Length | Value | 317 +--------+--------+----+-----------+ 318 |00000010|00000010|1011| MIUX | 319 +--------+--------+----+-----------+ 320 | <-------> | 321 0x000 ~ 0x7FF 323 Figure 4: Format of the MIUX Parameter TLV 325 When the MIUX parameter is encoded as a TLV, the TLV Type field SHALL 326 be 0x02 and the TLV Length field SHALL be 0x02. The MIUX parameter 327 SHALL be encoded into the least significant 11 bits of the TLV Value 328 field. The unused bits in the TLV Value field SHALL be set to zero 329 by the sender and SHALL be ignored by the receiver. However, a 330 maximun value of the TLV Value field can be 0x7FF, and a maximum size 331 of the MTU in NFC LLCP SHALL calculate 2176 bytes. 333 4. Specification of IPv6 over NFC 335 NFC technology sets also has considerations and requirements owing to 336 low power consumption and allowed protocol overhead. 6LoWPAN 337 standards RFC4944 [1], RFC6775 [4], and RFC6282 [5] provide useful 338 functionality for reducing overhead which can be applied to BT-LE. 339 This functionality comprises of link-local IPv6 addresses and 340 stateless IPv6 address auto-configuration (see Section 4.3), Neighbor 341 Discovery (see Section 4.5) and header compression (see Section 4.6). 343 One of the differences between IEEE 802.15.4 and NFC is that the 344 former supports both star and mesh topology (and requires a routing 345 protocol), whereas NFC can support direct peer-to-peer connection and 346 simple mesh-like topology depending on NFC application scenarios 347 because of very short RF distance of 10 cm or less. 349 4.1. Protocol Stacks 351 Figure 5 illustrates IPv6 over NFC. Upper layer protocols can be 352 transport protocols (TCP and UDP), application layer, and the others 353 capable running on the top of IPv6. 355 | | Transport & 356 | Upper Layer Protocols | Application Layer 357 +----------------------------------------+ <------------------ 358 | | | 359 | IPv6 | | 360 | | Network 361 +----------------------------------------+ Layer 362 | Adaptation Layer for IPv6 over NFC | | 363 +----------------------------------------+ <------------------ 364 | IPv6-LLCP Binding | 365 | Logical Link Control Protocol | NFC Link Layer 366 | (LLCP) | | 367 +----------------------------------------+ <------------------ 368 | | | 369 | Activities | NFC 370 | Digital Protocol | Physical Layer 371 | RF Analog | | 372 | | | 373 +----------------------------------------+ <------------------ 375 Figure 5: Protocol Stacks for IPv6 over NFC 377 Adaptation layer for IPv6 over NFC SHALL support neighbor discovery, 378 address auto-configuration, header compression, and fragmentation & 379 reassembly. 381 4.2. Link Model 383 In the case of BT-LE, Logical Link Control and Adaptation Protocol 384 (L2CAP) supports fragmentation and reassembly (FAR) functionality; 385 therefore, adaptation layer for IPv6 over BT-LE does not have to 386 conduct the FAR procedure. The NFC LLCP, by contrast, does not 387 support the FAR functionality, so IPv6 over NFC needs to consider the 388 FAR functionality, defined in RFC4944 [1]. However, MTU on NFC link 389 can be configured in a connection procedure and extended enough to 390 fit the MTU of IPv6 packet. 392 The NFC link between two communicating devices is considered to be a 393 point-to-point link only. Unlike in BT-LE, NFC link does not 394 consider star topology and mesh network topology but peer-to-peer 395 topology and simple multi-hop topology. Due to this characteristics, 396 6LoWPAN functionality, such as addressing and auto-configuration, and 397 header compression, is specialized into NFC. 399 4.3. Stateless Address Autoconfiguration 401 A NFC-enabled device (i.e., 6LN) performs stateless address 402 autoconfiguration as per RFC4862 [6]. A 64-bit Interface identifier 403 (IID) for a NFC interface MAY be formed by utilizing the 6-bit NFC 404 LLCP address (i.e., SSAP or DSAP) (see Section 3.3). In the 405 viewpoint of address configuration, such an IID MAY guarantee a 406 stable IPv6 address because each data link connection is uniquely 407 identified by the pair of DSAP and SSAP included in the header of 408 each LLC PDU in NFC. 410 Following the guidance of RFC7136 [10], interface Identifiers of all 411 unicast addresses for NFC-enabled devices are formed on the basis of 412 64 bits long and constructed in a modified EUI-64 format as shown in 413 Figure 6. 415 0 1 3 4 5 6 416 0 6 2 8 8 3 417 +----------------+----------------+----------------+----------+------+ 418 |0000000000000000|0000000011111111|1111111000000000|0000000000| SSAP | 419 +----------------+----------------+----------------+----------+------+ 421 Figure 6: Formation of IID from NFC-enabled device adddress 423 In addition, the "Universal/Local" bit in the case of NFC-enabled 424 device address MUST be set to 0 RFC4291 [7]. 426 4.4. IPv6 Link Local Address 428 Only if the NFC-enabled device address is known to be a public 429 address the "Universal/Local" bit can be set to 1. The IPv6 link- 430 local address for a NFC-enabled device is formed by appending the 431 IID, to the prefix FE80::/64, as depicted in Figure 7. 433 0 0 0 1 434 0 1 6 2 435 0 0 4 7 436 +----------+------------------+----------------------------+ 437 |1111111010| zeros | Interface Identifier | 438 +----------+------------------+----------------------------+ 439 | | 440 | <---------------------- 128 bits ----------------------> | 441 | | 443 Figure 7: IPv6 link-local address in NFC 445 The tool for a 6LBR to obtain an IPv6 prefix for numbering the NFC 446 network is can be accomplished via DHCPv6 Prefix Delegation (RFC3633 447 [8]). 449 4.5. Neighbor Discovery 451 Neighbor Discovery Optimization for 6LoWPANs (RFC6775 [4]) describes 452 the neighbor discovery approach in several 6LoWPAN topologies, such 453 as mesh topology. NFC does not consider complicated mesh topology 454 but simple multi-hop network topology or directly connected peer-to- 455 peer network. Therefore, the following aspects of RFC6775 are 456 applicable to NFC: 458 1. In a case that a NFC-enabled device (6LN) is directly connected 459 to 6LBR, A NFC 6LN MUST register its address with the 6LBR by 460 sending a Neighbor Solicitation (NS) message with the Address 461 Registration Option (ARO) and process the Neighbor Advertisement 462 (NA) accordingly. In addition, DHCPv6 is used to assigned an 463 address, Duplicate Address Detection (DAD) is not required. 465 2. For sending Router Solicitations and processing Router 466 Advertisements the NFC 6LNs MUST follow Sections 5.3 and 5.4 of 467 the RFC6775. 469 4.6. Header Compression 471 Header compression as defined in RFC6282 [5] , 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 NFC. All headers MUST be compressed according to RFC6282 475 encoding formats. 477 If a 16-bit address is required as a short address of IEEE 802.15.4, 478 it MUST be formed by padding the 6-bit NFC link-layer (node) address 479 to the left with zeros as shown in Figure 8. 481 0 1 482 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 483 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 484 | Padding(all zeros)| NFC Addr. | 485 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 487 Figure 8: NFC short adress format 489 4.7. Fragmentation and Reassembly 491 NFC provides fragmentation and reassembly (FAR) for payloads from 128 492 bytes up to 2176 bytes as mention in Section 3.4. The MTU of a 493 general IPv6 packet can fit into a sigle NFC link frame. Therefore, 494 the FAR functionality as defined in RFC4944, which specifies the 495 fragmentation methods for IPv6 datagrams on top of IEEE 802.15.4, is 496 NOT REQUIRED in this document as the basis for IPv6 datagram FAR on 497 top of NFC. The NFC link connection for IPv6 over NFC MUST be 498 configured with an equivalent MIU size to fit the MTU of IPv6 Packet. 499 However, the default configuration of MIUX value is 0x480 in order to 500 fit the MTU (1280 bytes) of a IPv6 packet. 502 4.8. Unicast Address Mapping 504 The address resolution procedure for mapping IPv6 non-multicast 505 addresses into NFC link-layer addresses follows the general 506 description in Section 7.2 of RFC4861 [9], unless otherwise 507 specified. 509 The Source/Target link-layer Address option has the following form 510 when the addresses are 6-bit NFC link-layer (node) addresses. 512 0 1 513 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 514 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 515 | Type | Length=1 | 516 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 517 | | 518 +- Padding (all zeros) -+ 519 | | 520 +- +-+-+-+-+-+-+ 521 | | NFC Addr. | 522 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 524 Figure 9: Unicast address mapping 526 Option fields: 528 Type: 530 1: for Source Link-layer address. 532 2: for Target Link-layer address. 534 Length: 536 This is the length of this option (including the type and 537 length fields) in units of 8 octets. The value of this field 538 is 1 for 6-bit NFC node addresses. 540 NFC address: 542 The 6-bit address in canonical bit order. This is the unicast 543 address the interface currently responds to. 545 4.9. Multicast Address Mapping 547 All IPv6 multicast packets MUST be sent to NFC Destination Address, 548 0x3F (broadcast) and filtered at the IPv6 layer. When represented as 549 a 16-bit address in a compressed header, it MUST be formed by padding 550 on the left with a zero. In addition, the NFC Destination Address, 551 0x3F, MUST not be used as a unicast NFC address of SSAP or DSAP. 553 0 1 554 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 555 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 556 | Padding(all zeros)|1 1 1 1 1 1| 557 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 559 Figure 10: Multicast address mapping 561 5. Internet Connectivity Scenarios 563 As two typical scenarios, the NFC network can be isolated and 564 connected to the Internet. 566 5.1. NFC-enabled Device Connected to the Internet 568 One of the key applications by using adaptation technology of IPv6 569 over NFC is the most securely transmitting IPv6 packets because RF 570 distance between 6LN and 6LBR SHOULD be within 10 cm. If any third 571 party wants to hack into the RF between them, it MUST come to nearly 572 touch them. Applications can choose which kinds of air interfaces 573 (e.g., BT-LE, Wi-Fi, NFC, etc.) to send data depending 574 characteristics of data. NFC SHALL be the best solution for secured 575 and private information. 577 Figure 11 illustrates an example of NFC-enabled device network 578 connected to the Internet. Distance between 6LN and 6LBR SHOULD be 579 10 cm or less. If there is any of close laptop computers to a user, 580 it SHALL becomes the 6LBR. Additionally, When the user mounts a NFC- 581 enabled air interface adapter (e.g., portable small NFC dongle) on 582 the close laptop PC, the user's NFC-enabled device (6LN) can 583 communicate the laptop PC (6LBR) within 10 cm distance. 585 ************ 586 6LN ------------------- 6LBR -----* Internet *------- CN 587 | (dis. 10 cm or less) | ************ | 588 | | | 589 | <-------- NFC -------> | <----- IPv6 packet ------> | 590 | (IPv6 over NFC packet) | | 592 Figure 11: NFC-enabled device network connected to the Internet 594 5.2. Isolated NFC-enabled Device Network 596 In some scenarios, the NFC-enabled device network may transiently be 597 a simple isolated network as shown in the Figure 12. 599 6LN ---------------------- 6LR ---------------------- 6LN 600 | (10 cm or less) | (10 cm or less) | 601 | | | 602 | <--------- NFC --------> | <--------- NFC --------> | 603 | (IPv6 over NFC packet) | (IPv6 over NFC packet) | 605 Figure 12: Isolated NFC-enabled device network 607 In mobile phone markets, applications are designed and made by user 608 developers. They may image interesting applications, where three or 609 more mobile phones touch or attach each other to accomplish 610 outstanding performance. For instance, three or more mobile phones 611 can play multi-channel sound of music together. In addition, 612 attached three or more mobile phones can make an extended banner to 613 show longer sentences in a concert hall. 615 6. IANA Considerations 617 There are no IANA considerations related to this document. 619 7. Security Considerations 621 The method of deriving Interface Identifiers from 6-bit NFC Link 622 layer addresses is intended to preserve global uniqueness when it is 623 possible. Therefore, it is to required to protect from duplication 624 through accident or forgery. 626 8. Acknowledgements 628 We are grateful to the members of the IETF 6lo working group. 630 Michael Richardson, Suresh Krishnan, Pascal Thubert, Carsten Bormann, 631 and Alexandru Petrescu have provided valuable feedback for this 632 draft. 634 9. References 636 9.1. Normative References 638 [1] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler, 639 "Transmission of IPv6 Packets over IEEE 802.15.4 640 Networks", RFC 4944, September 2007. 642 [2] Bradner, S., "Key words for use in RFCs to Indicate 643 Requirement Levels", BCP 14, RFC 2119, March 1997. 645 [3] "Logical Link Control Protocol version 1.1", NFC Forum 646 Technical Specification , June 2011. 648 [4] Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann, 649 "Neighbor Discovery Optimization for IPv6 over Low-Power 650 Wireless Personal Area Networks (6LoWPANs)", RFC 6775, 651 November 2012. 653 [5] Hui, J. and P. Thubert, "Compression Format for IPv6 654 Datagrams over IEEE 802.15.4-Based Networks", RFC 6282, 655 September 2011. 657 [6] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless 658 Address Autoconfiguration", RFC 4862, September 2007. 660 [7] Hinden, R. and S. Deering, "IP Version 6 Addressing 661 Architecture", RFC 4291, February 2006. 663 [8] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic 664 Host Configuration Protocol (DHCP) version 6", RFC 3633, 665 December 2003. 667 [9] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, 668 "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, 669 September 2007. 671 [10] Carpenter, B. and S. Jiang, "Significance of IPv6 672 Interface Identifiers", RFC 7136, February 2014. 674 9.2. Informative References 676 [11] "Near Field Communication - Interface and Protocol (NFCIP- 677 1) 3rd Ed.", ECMA-340 , June 2013. 679 Authors' Addresses 681 Yong-Geun Hong 682 ETRI 683 161 Gajeong-Dong Yuseung-Gu 684 Daejeon 305-700 685 Korea 687 Phone: +82 42 860 6557 688 Email: yghong@etri.re.kr 690 Younghwan Choi 691 ETRI 692 218 Gajeongno, Yuseong 693 Daejeon 305-700 694 Korea 696 Phone: +82 42 860 1429 697 Email: yhc@etri.re.kr 699 Joo-Sang Youn 700 DONG-EUI University 701 176 Eomgwangno Busan_jin_gu 702 Busan 614-714 703 Korea 705 Phone: +82 51 890 1993 706 Email: joosang.youn@gmail.com 708 Dongkyun Kim 709 Kyungpook National University 710 80 Daehak-ro, Buk-gu 711 Daegu 702-701 712 Korea 714 Phone: +82 53 950 7571 715 Email: dongkyun@knu.ac.kr 716 JinHyouk Choi 717 Samsung Electronics Co., 718 129 Samsung-ro, Youngdong-gu 719 Suwon 447-712 720 Korea 722 Phone: +82 2 2254 0114 723 Email: jinchoe@samsung.com