idnits 2.17.1 draft-thubert-6man-flow-label-for-rpl-02.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 'MAY NOT' 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. == The expression 'MAY NOT', while looking like RFC 2119 requirements text, is not defined in RFC 2119, and should not be used. Consider using 'MUST NOT' instead (if that is what you mean). Found 'MAY NOT' in this paragraph: This specification also allows that regardless of its original setting, a a root of a RPL domain MAY set low Label of IPv6 packets that exits the RPL domain MAY be set by the RPL, in a manner that SHOULD conform the prescriptions in [RFC6437], and that a source in the RPL domain MAY NOT expect that its setting of the Flow Label be preserved end-to-end. From there, the capability by RPL routers inside the LLN to alter a non-zero Flow Label between the source and the root is another minor deviation to [RFC6437] that is also acceptable since it is transparent to the core of the Internet. -- The document date (May 13, 2014) is 3635 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) -- Possible downref: Non-RFC (?) normative reference: ref. 'IEEE802154' ** Obsolete normative reference: RFC 2460 (Obsoleted by RFC 8200) == Outdated reference: A later version (-30) exists of draft-ietf-6tisch-architecture-01 == Outdated reference: A later version (-06) exists of draft-ietf-6tisch-tsch-00 == Outdated reference: A later version (-08) exists of draft-thubert-6lo-forwarding-fragments-01 Summary: 1 error (**), 0 flaws (~~), 5 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 6MAN P. Thubert, Ed. 3 Internet-Draft Cisco 4 Intended status: Standards Track May 13, 2014 5 Expires: November 14, 2014 7 The IPv6 Flow Label within a RPL domain 8 draft-thubert-6man-flow-label-for-rpl-02 10 Abstract 12 This document present how the Flow Label can be used inside a RPL 13 domain as a replacement to the RPL option and provides rules for the 14 root to set and reset the Flow Label when forwarding between the 15 inside of RPL domain and the larger Internet, in both direction. 16 This new operation saves 44 bits in each frame, and an eventual IP- 17 in-IP encapsulation within the RPL domain that is required for all 18 packets that reach outside of the RPL domain. 20 Status of This Memo 22 This Internet-Draft is submitted in full conformance with the 23 provisions of BCP 78 and BCP 79. 25 Internet-Drafts are working documents of the Internet Engineering 26 Task Force (IETF). Note that other groups may also distribute 27 working documents as Internet-Drafts. The list of current Internet- 28 Drafts is at http://datatracker.ietf.org/drafts/current/. 30 Internet-Drafts are draft documents valid for a maximum of six months 31 and may be updated, replaced, or obsoleted by other documents at any 32 time. It is inappropriate to use Internet-Drafts as reference 33 material or to cite them other than as "work in progress." 35 This Internet-Draft will expire on November 14, 2014. 37 Copyright Notice 39 Copyright (c) 2014 IETF Trust and the persons identified as the 40 document authors. All rights reserved. 42 This document is subject to BCP 78 and the IETF Trust's Legal 43 Provisions Relating to IETF Documents 44 (http://trustee.ietf.org/license-info) in effect on the date of 45 publication of this document. Please review these documents 46 carefully, as they describe your rights and restrictions with respect 47 to this document. Code Components extracted from this document must 48 include Simplified BSD License text as described in Section 4.e of 49 the Trust Legal Provisions and are provided without warranty as 50 described in the Simplified BSD License. 52 Table of Contents 54 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 55 1.1. On Wasted Energy . . . . . . . . . . . . . . . . . . . . 3 56 1.2. LLN flows . . . . . . . . . . . . . . . . . . . . . . . . 5 57 1.3. On Compatibility With Existing Standards . . . . . . . . 6 58 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 7 59 3. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 7 60 4. Flow Label Format Within the RPL Domain . . . . . . . . . . . 8 61 5. Root Operation . . . . . . . . . . . . . . . . . . . . . . . 8 62 5.1. Incoming Packets . . . . . . . . . . . . . . . . . . . . 9 63 5.2. Outgoing Packets . . . . . . . . . . . . . . . . . . . . 9 64 6. RPL node Operation . . . . . . . . . . . . . . . . . . . . . 9 65 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9 66 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 67 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 68 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 69 10.1. Normative References . . . . . . . . . . . . . . . . . . 10 70 10.2. Informative References . . . . . . . . . . . . . . . . . 10 71 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 11 73 1. Introduction 75 The emergence of radio technology enabled a large variety of new 76 types of devices to be interconnected, at a very low marginal cost 77 compared to wire, at any range from Near Field to interplanetary 78 distances, and in circumstances where wiring would be less than 79 practical, for instance rotating devices. 81 In particular, IEEE802.14.5 [IEEE802154] that is chartered to specify 82 PHY and MAC layers for radio Lowpower Lossy Networks (LLNs), defined 83 the TimeSlotted Channel Hopping [I-D.ietf-6tisch-tsch] (TSCH) mode of 84 operation as part of the IEEE802.15.4e MAC specification in order to 85 address Time Sensitive applications. 87 The 6TISCH architecture [I-D.ietf-6tisch-architecture] specifies the 88 operation IPv6 over TSCH wireless networks attached and synchronized 89 by backbone routers. 91 With 6TiSCH, the route Computation may be achieved in a centralized 92 fashion by a Path Computation Element (PCE), in a distributed fashion 93 using the Routing Protocol for Low Power and Lossy Networks [RFC6550] 94 (RPL), or in a mixed mode. 96 6TiSCH was created to simplify the adoption of IETF technology by 97 other Standard Defining Organizations (SDOs), in particular in the 98 Industrial Automation space, which already relies on variations of 99 IEEE802.15.4e TSCH for Wireless Sensor Networking. 101 ISA100.11a [ISA100.11a] is an example of such industrial WSN 102 standard, using IEEE802.15.4e over the classical IEEE802.14.5 PHY. 103 In that case, after security is applied, roughly 80 octets are 104 available per frame for IP and Payload. In order to 1) avoid 105 fragmentation and 2) conserve energy, the SDO will scrutinize any bit 106 in the frame and reject any waste. 108 The challenge to obtain the adoption of IPv6 in the original standard 109 was really to save any possible bit in the frames, including the UDP 110 checksum which was an interesting discussion on its own. This work 111 was actually one of the roots for the 6LoWPAN Header Compression 112 [RFC6282] work, which goes down to the individual bits to save space 113 in the frames for actual data, and allowed ISA100.11a to adopt IPv6. 115 1.1. On Wasted Energy 117 The design of Lowpower Lossy Networks is generally focussed on saving 118 energy, which is the most constrained resource of all. The other 119 constraints, such as the memory capacity and the duty cycling of the 120 LLN devices, derive from that primary concern. Energy is typically 121 available from batteries that are expected to last for years, or 122 scavenged from the environment in very limited quantities. Any 123 protocol that is intended for use in LLNs must be designed with the 124 primary concern of saving energy as a strict requirement. 126 The Routing Protocol for Low Power and Lossy Networks (RPL) [RFC6550] 127 specification defines a generic Distance Vector protocol that is 128 indeed designed for very low energy consumption and adapted to a 129 variety of LLNs. RPL forms Destination Oriented Directed Acyclic 130 Graphs (DODAGs) which root often acts as the Border Router to connect 131 the RPL domain to the Internet. The root is responsible to select 132 the RPL Instance that is used to forward a packet coming from the 133 Internet into the RPL domain and set the related RPL information in 134 the packets. 136 A classical RPL implementation will use the RPL Option for Carrying 137 RPL Information in Data-Plane Datagrams [RFC6553] to tag a packet 138 with the Instance ID and other information that RPL requires for its 139 operation within the RPL domain. In particular, the Rank, which is 140 the scalar metric computed by an specialized Objective Function such 141 as [RFC6552], is modified at each hop and allows to validate that the 142 packet progresses in the expected direction each upwards or downwards 143 in along the DODAG. 145 With [RFC6553], the RPL option is encoded as 6 Octets; it must be 146 placed in a Hop-by-Hop header that represents 2 additional octets for 147 a total of 8. In order to limit its range to the inside the RPL 148 domain, the Hop-by-Hop header must be added to (or removed from) 149 packets that cross the border of the RPL domain. For reasons such as 150 the capability to send ICMP errors back to the source, this operation 151 involves an extra IP-in-IP encapsulation inside the RPL domain for 152 all the packets which path is not contained within the RPL domain. 154 The 8-octets overhead is detrimental to the LLN operation, in 155 particular with regards to bandwidth and battery constraints. The 156 extra encapsulation may cause a containing frame to grow above 157 maximum frame size, leading to Layer 2 or 6LoWPAN [RFC4944] 158 fragmentation, which in turn cause even more energy spending and 159 issues discussed in the LLN Fragment Forwarding and Recovery 160 [I-D.thubert-6lo-forwarding-fragments]. 162 ------+--------- ^ 163 | Internet | 164 | | Native IPv6 165 +-----+ | 166 | | Border Router (RPL Root) ^ | ^ 167 | | | | | 168 +-----+ | | | IPv6 + 169 | | | | HbH 170 o o o o | | | headers 171 o o o o o o o o o | | | 172 o o o o o o o o o o | | | 173 o o o o o o o o o | | | 174 o o o o o o o o v v v 175 o o o o o o 176 o o o o 178 LLN 180 Figure 1: IP-in-IP Encapsulation within the LLN 182 Considering that, in the classical IEEE802.14.5 PHY that is used by 183 ISA100.11a, roughly 80 octets are available per frame after security 184 is applied, and any additional transmitted bit weights in the energy 185 consumption and drains the batteries. 187 Regrettably, [RFC6282] does not provide an efficient compression for 188 the RPL option so the cost in current implementations can not be 189 alleviated in any fashion. So even for packets that are confined 190 within the RPL domain and do not need the IP-in-IP encapsulation, the 191 use of the flow label instead of the RPL option would be a valuable 192 saving. 194 1.2. LLN flows 196 In Industrial Automation and Control Systems (IACS) [RFC5673], a 197 packet loss is usually acceptable but jitter and latency must be 198 strictly controlled as they can play a critical role in the 199 interpretation of the measured information. Sensory systems are 200 often distributed, and the control information can in fact be 201 originated from multiple sources and aggregated. In such cases, 202 related packets from multiple sources should not be load-balanced 203 along their path in the Internet. 205 In a typical LLN application, the bulk of the traffic consists of 206 small chunks of data (in the order few bytes to a few tens of bytes) 207 at a time. 4Hz is a typical loop frequency in Process Control, 208 though it can be a lot slower than that in, say, environmental 209 monitoring. The granularity of traffic from a single source is too 210 small to make a lot of sense in load balancing application. 212 As a result, it can be a requirement for related measurements from 213 multiple sources to be treated as a single flow following a same path 214 over the Internet so as to experience similar jitter and latency. 215 The traditional tuple of source, destination and ports might then not 216 be the proper indication to isolate a consistent flow. On the other 217 hand, the flow integrity can be preserved in a simple manner if the 218 setting of the Flow Label in the IPv6 header of packets outgoing a 219 RPL domain, is centralized to the root of the RPL DODAG structure, as 220 opposed to distributed across the actual sources. 222 Considering that the goal for setting the Flow Label as prescribed in 223 the IPv6 Flow Label Specification [RFC6437] is to improve load 224 balancing in the core of the Internet, it is unlikely that LLN 225 devices will consume energy to generate and then transmit a Flow 226 Label to serve outside interests and the Flow Label is generally left 227 to zero so as to be elided in the 6LoWPAN [RFC6282] compression. So 228 in a general manner the interests of the core are better served if 229 the RPL roots systematically rewrite the flow label rather than if 230 they never do. 232 For packets coming into the RPL domain from the Internet, the value 233 for setting the Flow Label as prescribed in [RFC6437] is consumed 234 once the packet has traversed the core and reaches the LLN. Then 235 again, there is little value but a high cost for the LLN in spending 236 20 bits to transport a Flow Label from the Internet over the 237 constrained network to a destination node that has no use of it. 239 1.3. On Compatibility With Existing Standards 241 All the packets from all the nodes in a same DODAG that are leaving a 242 RPL domain towards the Internet will transit via a same RPL root. 243 The RPL root segregates the Internet and the RPL domain, which 244 enables the capability to reuse the Flow Label within the RPL domain. 246 On the other hand, the operation of resetting or reusing the IPv6 247 Flow Label at the root of a RPL domain is a deviation from the IPv6 248 Flow Label Specification [RFC6437], in that it is neither the source 249 nor the first hop router that sets the final Flow Label for use 250 outside the RPL domain. 252 Additionally, using the Flow Label to transport the information that 253 is classically present in the RPL option implies that the Flow Label 254 is modified at each hop inside the RPL domain, which again is a 255 limited deviation from [RFC6437], which explicitly requires that the 256 flow label cannot be modified once set. 258 But if we consider the whole RPL domain as a large virtual host from 259 the standpoint of the rest of the Internet, the interests that lead 260 to [RFC6437], and in particular load balancing in the core of the 261 Internet, are probably better served if the root guarantees that the 262 Flow Label is set in a compliant fashion than if we rely on each 263 individual sensor that may not use it at all, or use it slightly 264 differently such as done in ISA100.11a. 266 Additionally, LLN flows can be compound flows aggregating information 267 from multiple sources. The root is an ideal place to rewrite the 268 Flow Label to a same value for a same flow across multiple sources, 269 ensuring compliance with the rules defined by [RFC6437] for use 270 outside of the RPL domain and in particular in the core of the 271 Internet. 273 It can be noted that [RFC6282] provides an efficient header 274 compression for packets that do have the Flow Label set in the IPv6 275 header. It results that the overhead for transporting the RPL 276 information can be down from 64 to 20 bits, alleviating at the same 277 time the need for IP-in-IP encapsulation. This optimization cannot 278 be ignored, and can make the difference for the adoption of RPL and 279 6TiSCH by external standard bodies. 281 This document specifies how the Flow Label can be reused within the 282 RPL domain as a replacement to the RPL option. The use of the Flow 283 Label within a RPL domain is an instance of the stateful scenarios as 284 discussed in [RFC6437] where the states include the Rank of a node 285 and the RPLInstanceID that identifies the routing topology. 287 2. Terminology 289 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 290 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 291 document are to be interpreted as described in [RFC2119]. 293 The Terminology used in this document is consistent with and 294 incorporates that described in `Terminology in Low power And Lossy 295 Networks' [RFC7102] and [RFC6550]. 297 3. Applicability 299 This specification applies to a RPL [RFC6282] domain that forms a 300 stub LLN and is connected to the Internet by and only by its RPL 301 root(s), which act(s) as Border Router(s) for the LLN. With RPL, a 302 root is the bottleneck for all the traffic between the Internet and 303 the Destination-Oriented Directed Acyclic Graph (DODAG) that it 304 serves. 306 In that context, the specification entitles a RPL root to rewrite the 307 IPv6 [RFC2460] Flow Label of all packets entering or leaving the RPL 308 domain in both directions, from and towards the Internet, regardless 309 of its original setting. This may seem contradictory with the IPv6 310 Flow Label Specification [RFC6437] which stipulates that once it is 311 set, the Flow Label is left unchanged; but the RFC also indicates a 312 violation to the rule can be accepted for compelling reasons, and 313 that security is a case justifying such a violation. This 314 specification suggests that energy-saving is another compelling 315 reason for a violation to the aforementioned rule. 317 For the compelling reason of saving energy, this specification allows 318 that regardless of its original setting, a root of a RPL domain MAY 319 reset the Flow Label of IPv6 packets entering the RPL domain to zero 320 for an optimal Header Compression by 6LoWPAN [RFC6282]. The 321 specification also allows that the root and LLN routers MAY reuse the 322 Flow Label inside the LLN for LLN purposes, such as to carry the RPL 323 Information as detailed hereafter. 325 This specification also allows that regardless of its original 326 setting, a a root of a RPL domain MAY set low Label of IPv6 packets 327 that exits the RPL domain MAY be set by the RPL, in a manner that 328 SHOULD conform the prescriptions in [RFC6437], and that a source in 329 the RPL domain MAY NOT expect that its setting of the Flow Label be 330 preserved end-to-end. From there, the capability by RPL routers 331 inside the LLN to alter a non-zero Flow Label between the source and 332 the root is another minor deviation to [RFC6437] that is also 333 acceptable since it is transparent to the core of the Internet. 335 4. Flow Label Format Within the RPL Domain 337 [RFC6550] section 11.2 specifies the fields that are to be placed 338 into the packets for the purpose of Instance Identification, as well 339 as Loop Avoidance and Detection. Those fields include an 'O', and 340 'R' and an 'F' bits, the 8-bit RPLInstanceID, and the 16-bit 341 SenderRank. SenderRank is the result of the DAGRank operation on the 342 rank of the sender, where the DAGRank operation is defined in section 343 3.5.1 as: 345 DAGRank(rank) = floor(rank/MinHopRankIncrease) 347 If MinHopRankIncrease is set to a multiple of 256, it appears that 348 the most significant 8 bits of the SenderRank will be all zeroes and 349 could be omitted. In that case, the Flow Label MAY be used as a 350 replacement to the [RFC6553] RPL option. To achieve this, the 351 SenderRank is expressed with 8 least significant bits, and the 352 information carried within the Flow Label in a packet is constructed 353 follows: 355 0 1 2 356 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 357 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 358 | |O|R|F| SenderRank | RPLInstanceID | 359 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 361 Figure 1: The RPL Flow Label 363 The first (leftmost) bit of the Flow Label is reserved and should be 364 set to zero. 366 5. Root Operation 368 [RFC6437] section 3 intentionally does not consider flow label values 369 in which any of the bits have semantic significance. However, the 370 present specification assigns semantics to various bits in the flow 371 label, destroying within the edge network that is the RPL domain the 372 property of belonging to a statistically uniform distribution that is 373 desirable in the rest of the Internet. 375 It can be noted that the rationale for the statistically uniform 376 distribution does not necessarily bring a lot of value within the RPL 377 domain. In a specific use case where it would, that value must be 378 compared with that of the battery savings in order to decide which 379 technique the deployment will use to transport the RPL information. 381 5.1. Incoming Packets 383 When routing a packet towards the RPL domain, the root applies a 384 policy to determine whether the Flow Label is to be used to carry the 385 RPL information. If so, the root MUST reset the Flow Label and then 386 it MUST set all the fields in the Flow Label as prescribed by 387 [RFC6553] using the format specified in Figure 1. In particular, the 388 root selects the Instance that will be used to forward the packet 389 within the RPL domain. 391 5.2. Outgoing Packets 393 When routing a packet outside the RPL domain, the root applies a 394 policy to determine whether the Flow Label was used to carry the RPL 395 information. If so, the root MUST reset the Flow Label. The root 396 SHOULD recompute a Flow Label following the rules prescribed by 397 [RFC6553]. In particular, the root MAY ignore the source address but 398 it SHOULD use the RPLInstanceID for the computation. 400 6. RPL node Operation 402 Depending on the policy in place, the source of a packet will decide 403 whether to use this specification to transport the RPL information in 404 the IPv6 packets. If it does, the source in the LLN SHOULD set the 405 Flow Label to zero and MUST NOT expect that the flow label will be 406 conserved end-to-end". 408 7. Security Considerations 410 Because the flow label is not protected by IPSec, it is expected that 411 Layer-2 security is deployed in the LLN where is specification is 412 applied. This is the actual best practice in LLNs, which serves in 413 particular to avoid forwarding of untrusted packets over the 414 constrained network. 416 If the link layer is secured adequately, using the Flow Label as 417 opposed to the RPL option does not create an opening for a new threat 418 compared to [RFC6553]. 420 8. IANA Considerations 422 No IANA action is required for this specification. 424 9. Acknowledgements 426 The author wishes to thank Brian Carpenter for his in-depth review 427 and constructive approach to the problem resolution. 429 10. References 431 10.1. Normative References 433 [IEEE802154] 434 IEEE standard for Information Technology, "IEEE std. 435 802.15.4, Part. 15.4: Wireless Medium Access Control (MAC) 436 and Physical Layer (PHY) Specifications for Low-Rate 437 Wireless Personal Area Networks", June 2011. 439 [ISA100.11a] 440 ISA, "ISA100, Wireless Systems for Automation", May 2008, 441 < http://www.isa.org/Community/ 442 SP100WirelessSystemsforAutomation>. 444 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 445 Requirement Levels", BCP 14, RFC 2119, March 1997. 447 [RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6 448 (IPv6) Specification", RFC 2460, December 1998. 450 [RFC6282] Hui, J. and P. Thubert, "Compression Format for IPv6 451 Datagrams over IEEE 802.15.4-Based Networks", RFC 6282, 452 September 2011. 454 [RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme, 455 "IPv6 Flow Label Specification", RFC 6437, November 2011. 457 [RFC6550] Winter, T., Thubert, P., Brandt, A., Hui, J., Kelsey, R., 458 Levis, P., Pister, K., Struik, R., Vasseur, JP., and R. 459 Alexander, "RPL: IPv6 Routing Protocol for Low-Power and 460 Lossy Networks", RFC 6550, March 2012. 462 [RFC6552] Thubert, P., "Objective Function Zero for the Routing 463 Protocol for Low-Power and Lossy Networks (RPL)", RFC 464 6552, March 2012. 466 [RFC6553] Hui, J. and JP. Vasseur, "The Routing Protocol for Low- 467 Power and Lossy Networks (RPL) Option for Carrying RPL 468 Information in Data-Plane Datagrams", RFC 6553, March 469 2012. 471 10.2. Informative References 473 [I-D.ietf-6tisch-architecture] 474 Thubert, P., Watteyne, T., and R. Assimiti, "An 475 Architecture for IPv6 over the TSCH mode of IEEE 476 802.15.4e", draft-ietf-6tisch-architecture-01 (work in 477 progress), February 2014. 479 [I-D.ietf-6tisch-tsch] 480 Watteyne, T., Palattella, M., and L. Grieco, "Using 481 IEEE802.15.4e TSCH in an LLN context: Overview, Problem 482 Statement and Goals", draft-ietf-6tisch-tsch-00 (work in 483 progress), November 2013. 485 [I-D.thubert-6lo-forwarding-fragments] 486 Thubert, P. and J. Hui, "LLN Fragment Forwarding and 487 Recovery", draft-thubert-6lo-forwarding-fragments-01 (work 488 in progress), February 2014. 490 [RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler, 491 "Transmission of IPv6 Packets over IEEE 802.15.4 492 Networks", RFC 4944, September 2007. 494 [RFC5673] Pister, K., Thubert, P., Dwars, S., and T. Phinney, 495 "Industrial Routing Requirements in Low-Power and Lossy 496 Networks", RFC 5673, October 2009. 498 [RFC7102] Vasseur, JP., "Terms Used in Routing for Low-Power and 499 Lossy Networks", RFC 7102, January 2014. 501 Author's Address 503 Pascal Thubert (editor) 504 Cisco Systems 505 Village d'Entreprises Green Side 506 400, Avenue de Roumanille 507 Batiment T3 508 Biot - Sophia Antipolis 06410 509 FRANCE 511 Phone: +33 4 97 23 26 34 512 Email: pthubert@cisco.com