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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Networking Working Group S. Previdi, Ed. 3 Internet-Draft Cisco Systems, Inc. 4 Intended status: Standards Track S. Giacalone 5 Expires: August 29, 2013 Thomson Reuters 6 D. Ward 7 Cisco Systems, Inc. 8 J. Drake 9 A. Atlas 10 Juniper Networks 11 C. Filsfils 12 Cisco Systems, Inc. 13 February 25, 2013 15 IS-IS Traffic Engineering (TE) Metric Extensions 16 draft-previdi-isis-te-metric-extensions-03 18 Abstract 20 In certain networks, such as, but not limited to, financial 21 information networks (e.g. stock market data providers), network 22 performance criteria (e.g. latency) are becoming as critical to data 23 path selection as other metrics. 25 This document describes extensions to IS-IS TE [RFC5305] such that 26 network performance information can be distributed and collected in a 27 scalable fashion. The information distributed using ISIS TE Metric 28 Extensions can then be used to make path selection decisions based on 29 network performance. 31 Note that this document only covers the mechanisms with which network 32 performance information is distributed. The mechanisms for measuring 33 network performance or acting on that information, once distributed, 34 are outside the scope of this document. 36 Requirements Language 38 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 39 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 40 document are to be interpreted as described in RFC 2119 [RFC2119]. 42 In this document, these words will appear with that interpretation 43 only when in ALL CAPS. Lower case uses of these words are not to be 44 interpreted as carrying RFC-2119 significance. 46 Status of this Memo 48 This Internet-Draft is submitted in full conformance with the 49 provisions of BCP 78 and BCP 79. 51 Internet-Drafts are working documents of the Internet Engineering 52 Task Force (IETF). Note that other groups may also distribute 53 working documents as Internet-Drafts. The list of current Internet- 54 Drafts is at http://datatracker.ietf.org/drafts/current/. 56 Internet-Drafts are draft documents valid for a maximum of six months 57 and may be updated, replaced, or obsoleted by other documents at any 58 time. It is inappropriate to use Internet-Drafts as reference 59 material or to cite them other than as "work in progress." 61 This Internet-Draft will expire on August 29, 2013. 63 Copyright Notice 65 Copyright (c) 2013 IETF Trust and the persons identified as the 66 document authors. All rights reserved. 68 This document is subject to BCP 78 and the IETF Trust's Legal 69 Provisions Relating to IETF Documents 70 (http://trustee.ietf.org/license-info) in effect on the date of 71 publication of this document. Please review these documents 72 carefully, as they describe your rights and restrictions with respect 73 to this document. Code Components extracted from this document must 74 include Simplified BSD License text as described in Section 4.e of 75 the Trust Legal Provisions and are provided without warranty as 76 described in the Simplified BSD License. 78 Table of Contents 80 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 81 2. TE Metric Extensions to IS-IS . . . . . . . . . . . . . . . . 4 82 3. Interface and Neighbor Addresses . . . . . . . . . . . . . . . 6 83 4. Sub TLV Details . . . . . . . . . . . . . . . . . . . . . . . 6 84 4.1. Unidirectional Link Delay Sub-TLV . . . . . . . . . . . . 6 85 4.2. Unidirectional Delay Variation Sub-TLV . . . . . . . . . . 7 86 4.3. Unidirectional Link Loss Sub-TLV . . . . . . . . . . . . . 8 87 4.4. Unidirectional Residual Bandwidth Sub-TLV . . . . . . . . 9 88 4.5. Unidirectional Available Bandwidth Sub-TLV . . . . . . . . 10 89 5. Announcement Thresholds and Filters . . . . . . . . . . . . . 10 90 6. Announcement Suppression . . . . . . . . . . . . . . . . . . . 11 91 7. Network Stability and Announcement Periodicity . . . . . . . . 11 92 8. Compatibility . . . . . . . . . . . . . . . . . . . . . . . . 11 93 9. Security Considerations . . . . . . . . . . . . . . . . . . . 11 94 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 95 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12 96 12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 97 12.1. Normative References . . . . . . . . . . . . . . . . . . . 12 98 12.2. Informative References . . . . . . . . . . . . . . . . . . 13 99 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 101 1. Introduction 103 This document describes extensions to IS-IS Extended Reachability TLV 104 defined in [RFC5305] (hereafter called "IS-IS TE Metric Extensions"), 105 that can be used to distribute network performance information (such 106 as link delay, delay variation, packet loss, residual bandwidth, and 107 available bandwidth). 109 In certain networks, such as, but not limited to, financial 110 information networks (e.g. stock market data providers), network 111 performance information (e.g. latency) is becoming as critical to 112 data path selection as other metrics. 114 The data distributed by the TE Metric Extensions proposed in this 115 document is meant to be used as part of the operation of the routing 116 protocol (e.g. by replacing cost with latency or considering 117 bandwidth as well as cost), by enhancing Constrained-SPF (CSPF), or 118 for other uses such as supplementing the data used by an ALTO server 119 [I-D.ietf-alto-protocol]. With respect to CSPF, the data distributed 120 by ISIS TE Metric Extensions can be used to setup, fail over, and 121 fail back data paths using protocols such as RSVP-TE [RFC3209]; 122 [I-D.atlas-mpls-te-express-path] describes some methods for using 123 this information to compute Label Switched Paths (LSPs) at the LSP 124 ingress. 126 Note that the mechanisms described in this document only disseminate 127 performance information. The methods for initially gathering that 128 performance information, such as [RFC6375], or acting on it once it 129 is distributed are outside the scope of this document. Example 130 mechanisms to measure latency, delay variation, and loss in an MPLS 131 network are given in [RFC6374]. While this document does not specify 132 how the performance information should be obtained, the measurement 133 of delay SHOULD NOT vary significantly based upon the offered traffic 134 load. Thus, queuing delays SHOULD NOT be included in the delay 135 measurement. For links, such as Forwarding Adjacencies, care must be 136 taken that measurement of the associated delay avoids significant 137 queuing delay; that could be accomplished in a variety of ways, 138 including either by measuring with a traffic class that experiences 139 minimal queuing or by summing the measured link delays of the 140 components of the link's path. 142 2. TE Metric Extensions to IS-IS 144 This document proposes new IS-IS TE sub-TLVs that can be announced in 145 ISIS Extended Reachability TLV (TLV-22) to distribute network 146 performance information. The extensions in this document build on 147 the ones provided in IS-IS TE [RFC5305] and GMPLS [RFC4203]. 149 IS-IS Extended Reachability TLV 22 (defined in [RFC5305]), Inter-AS 150 reachability information TLV 141 (defined in [RFC5316]) and MT-ISN 151 TLV 222 (defined in [RFC5120]) have nested sub-TLVs which permit the 152 TLVs to be readily extended. This document proposes several 153 additional sub-TLVs: 155 Type Value 157 TBD1 Unidirectional Link Delay 159 TBD2 Unidirectional Delay Variation 161 TBD3 Unidirectional Packet Loss 163 TBD4 Unidirectional Residual Bandwidth Sub TLV 165 TBD5 Unidirectional Available Bandwidth Sub TLV 167 As can be seen in the list above, the sub-TLVs described in this 168 document carry different types of network performance information. 169 The new sub-TLVs include a bit called the Anomalous (or "A") bit. 170 When the A bit is clear (or when the sub-TLV does not include an A 171 bit), the sub-TLV describes steady state link performance. This 172 information could conceivably be used to construct a steady state 173 performance topology for initial tunnel path computation, or to 174 verify alternative failover paths. 176 When network performance violates configurable link-local thresholds 177 a sub-TLV with the A bit set is advertised. These sub-TLVs could be 178 used by the receiving node to determine whether to fail traffic to a 179 backup path, or whether to calculate an entirely new path. From an 180 MPLS perspective, the intent of the A bit is to permit LSP ingress 181 nodes to: 183 A) Determine whether the link referenced in the sub-TLV affects any 184 of the LSPs for which it is ingress. If there are, then: 186 B) Determine whether those LSPs still meet end-to-end performance 187 objectives. If not, then: 189 C) The node could then conceivably move affected traffic to a pre- 190 established protection LSP or establish a new LSP and place the 191 traffic in it. 193 If link performance then improves beyond a configurable minimum value 194 (reuse threshold), that sub-TLV can be re-advertised with the 195 Anomalous bit cleared. In this case, a receiving node can 196 conceivably do whatever re-optimization (or failback) it wishes to do 197 (including nothing). 199 Note that when a sub-TLV does not include the A bit, that sub-TLV 200 cannot be used for failover purposes. The A bit was intentionally 201 omitted from some sub-TLVs to help mitigate oscillations. See 202 Section 5 for more information. 204 Consistent with existing IS-IS TE specifications [RFC5305], the 205 bandwidth advertisements defined in this draft MUST be encoded as 206 IEEE floating point values. The delay and delay variation 207 advertisements defined in this draft MUST be encoded as integer 208 values. Delay values MUST be quantified in units of microseconds, 209 packet loss MUST be quantified as a percentage of packets sent, and 210 bandwidth MUST be sent as bytes per second. All values (except 211 residual bandwidth) MUST be calculated as rolling averages where the 212 averaging period MUST be a configurable period of time. See 213 Section 5 for more information. 215 3. Interface and Neighbor Addresses 217 The use of TE Metric Extensions SubTLVs is not confined to the TE 218 context. In other words, IS-IS TE Metric Extensions SubTLVs defined 219 in this document can also be used for computing paths in the absence 220 of a TE subsystem. 222 However, as for the TE case, Interface Address and Neighbor Address 223 SubTLVs (IPv4 or IPv6) MUST be present. The encoding is defined in 224 [RFC5305] for IPv4 and in [RFC6119] for IPv6. 226 4. Sub TLV Details 228 4.1. Unidirectional Link Delay Sub-TLV 230 This sub-TLV advertises the average link delay between two directly 231 connected IS-IS neighbors. The delay advertised by this sub-TLV MUST 232 be the delay from the local neighbor to the remote one (i.e. the 233 forward path latency). The format of this sub-TLV is shown in the 234 following diagram: 236 0 1 2 3 237 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 238 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 239 | Type | Length |A| RESERVED | Delay | 240 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 241 | Delay | 242 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 244 This sub-TLV has a type of TBD1. 245 The length is 4. 247 Where: 249 "A" represents the Anomalous (A) bit. The A bit is set when the 250 measured value of this parameter exceeds its configured maximum 251 threshold. The A bit is cleared when the measured value falls below 252 its configured reuse threshold. If the A bit is clear, the sub-TLV 253 represents steady state link performance. 255 The "Reserved" field is reserved for future use. It MUST be set to 0 256 when sent and MUST be ignored when received. 258 "Delay Value" is a 24-bit field carries the average link delay over a 259 configurable interval in micro-seconds, encoded as an integer value. 260 When set to 0, it has not been measured. When set to the maximum 261 value 16,777,215 (16.777215 sec), then the delay is at least that 262 value and may be larger. 264 4.2. Unidirectional Delay Variation Sub-TLV 266 This sub-TLV advertises the average link delay variation between two 267 directly connected IS-IS neighbors. The delay variation advertised 268 by this sub-TLV MUST be the delay from the local neighbor to the 269 remote one (i.e. the forward path latency). The format of this sub- 270 TLV is shown in the following diagram: 272 0 1 2 3 273 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 274 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 275 | Type | Length |A| RESERVED |Delay Variation| 276 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 277 | Delay Variation | 278 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 280 This sub-TLV has a type of TBD2. 281 The length is 4. 283 Where: 285 "A" represents the Anomalous (A) bit. The A bit is set when the 286 measured value of this parameter exceeds its configured maximum 287 threshold. The A bit is cleared when the measured value falls below 288 its configured reuse threshold. If the A bit is clear, the sub-TLV 289 represents steady state link performance. 291 The "Reserved" field is reserved for future use. It MUST be set to 0 292 when sent and MUST be ignored when received. 294 "Delay Variation" is a 24-bit field carries the average link delay 295 variation over a configurable interval in micro-seconds, encoded as 296 an integer value. When set to 0, it has not been measured. When set 297 to the maximum value 16,777,215 (16.777215 sec), then the delay is at 298 least that value and may be larger. 300 4.3. Unidirectional Link Loss Sub-TLV 302 This sub-TLV advertises the loss (as a packet percentage) between two 303 directly connected IS-IS neighbors. The link loss advertised by this 304 sub-TLV MUST be the packet loss from the local neighbor to the remote 305 one (i.e. the forward path loss). The format of this sub-TLV is 306 shown in the following diagram: 308 0 1 2 3 309 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 310 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 311 | Type | Length |A| RESERVED | Link Loss | 312 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 313 | Link Loss | 314 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 316 This sub-TLV has a type of TBD3. 317 The length is 4. 319 Where: 321 The "A" bit represents the Anomalous (A) bit. The A bit is set when 322 the measured value of this parameter exceeds its configured maximum 323 threshold. The A bit is cleared when the measured value falls below 324 its configured reuse threshold. If the A bit is clear, the sub-TLV 325 represents steady state link performance. 327 "Reserved" field is reserved for future use. It MUST be set to 0 328 when sent and MUST be ignored when received. 330 "Link Loss" is a 24-bit field carries link packet loss as a 331 percentage of the total traffic sent over a configurable interval. 333 The basic unit is 0.000003%, where (2^24 - 2) is 50.331642%. This 334 value is the highest packet loss percentage that can be expressed 335 (the assumption being that precision is more important on high speed 336 links than the ability to advertise loss rates greater than this, and 337 that high speed links with over 50% loss are unusable). Therefore, 338 measured values that are larger than the field maximum SHOULD be 339 encoded as the maximum value. When set to a value of all 1s (2^24 - 340 1), the link packet loss has not been measured. 342 4.4. Unidirectional Residual Bandwidth Sub-TLV 344 This TLV advertises the residual bandwidth between two directly 345 connected IS-IS neighbors. The residual bandwidth advertised by this 346 sub-TLV MUST be the residual bandwidth from the system originating 347 the sub-TLV to its neighbor. The format of this sub-TLV is shown in 348 the following diagram: 350 0 1 2 3 351 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 352 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 353 | Type | Length |A| RESERVED | Residual | 354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 355 | Bandwidth | 356 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 358 This sub-TLV has a type of TBD4. 359 The length is 5. 361 Where: 363 The "A" bit represents the Anomalous (A) bit. The A bit is set when 364 the measured value of this parameter exceeds its configured maximum 365 threshold. The A bit is cleared when the measured value falls below 366 its configured reuse threshold. If the A bit is clear, the sub-TLV 367 represents steady state link performance. 369 "Residual Bandwidth" is the residual bandwidth in IEEE floating point 370 format in units of bytes per second. The link may be a single link, 371 forwarding adjacency [RFC4206], or bundled link. For a link or 372 forwarding adjacency, residual bandwidth is defined to be Maximum 373 Link Bandwidth [RFC5305] minus the bandwidth currently allocated to 374 RSVP-TE LSPs. For a bundled link, residual bandwidth is defined to 375 be the sum of the component link residual bandwidths. 377 Note that although it may seem possible to calculate Residual 378 Bandwidth using the existing sub-TLVs in [RFC5305], this is not a 379 consistently reliable approach and hence the Residual Bandwidth sub- 380 TLV has been added here. For example, because the Maximum Reservable 381 Bandwidth [RFC5305] can be larger than the capacity of the link, 382 using it as part of an algorithm to determine the value of the 383 Maximum Link Bandwidth [RFC5305]minus the bandwidth currently 384 allocated to RSVP-TE Label Switched Paths cannot be considered 385 reliably accurate. 387 4.5. Unidirectional Available Bandwidth Sub-TLV 389 This TLV advertises the available bandwidth between two directly 390 connected IS-IS neighbors. The available bandwidth advertised in 391 this sub-TLV MUST be the available bandwidth from the originating 392 system to its neighbor. The format of this sub-TLV is shown in the 393 following diagram: 395 0 1 2 3 396 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 397 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 398 | Type | Length |A| RESERVED | Available | 399 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 400 | Bandwidth | 401 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 403 This sub-TLV has a type of TBD5. 404 The length is 5. 406 Where: 408 The "A" bit represents the Anomalous (A) bit. The A bit is set when 409 the measured value of this parameter exceeds its configured maximum 410 threshold. The A bit is cleared when the measured value falls below 411 its configured reuse threshold. If the A bit is clear, the sub-TLV 412 represents steady state link performance. 414 "Available Bandwidth" is a field that carries the available bandwidth 415 on a link, forwarding adjacency, or bundled link in IEEE floating 416 point format with units of bytes per second. For a link or 417 forwarding adjacency, available bandwidth is defined to be residual 418 bandwidth (see Section 4.4) minus the measured bandwidth used for the 419 actual forwarding of non-RSVP-TE Label Switched Paths packets. For a 420 bundled link, available bandwidth is defined to be the sum of the 421 component link available bandwidths. 423 5. Announcement Thresholds and Filters 425 The values advertised in all sub-TLVs MUST be controlled using an 426 exponential filter (i.e. a rolling average) with a configurable 427 measurement interval and filter coefficient. 429 Implementations are expected to provide separately configurable 430 advertisement thresholds. All thresholds MUST be configurable on a 431 per sub-TLV basis. 433 The announcement of all sub-TLVs that do not include the A bit SHOULD 434 be controlled by variation thresholds that govern when they are sent. 436 Sub-TLVs that include the A bit are governed by several thresholds. 437 Firstly, a threshold SHOULD be implemented to govern the announcement 438 of sub-TLVs that advertise a change in performance, but not an SLA 439 violation (i.e. when the A bit is not set). Secondly, 440 implementations MUST provide configurable thresholds that govern the 441 announcement of sub-TLVs with the A bit set (for the indication of a 442 performance violation). Thirdly, implementations SHOULD provide 443 reuse thresholds. These thresholds govern sub-TLV re-announcement 444 with the A bit cleared to permit fail back. 446 6. Announcement Suppression 448 When link performance average values change, but fall under the 449 threshold that would cause the announcement of a sub-TLV with the A 450 bit set, implementations MAY suppress or throttle sub-TLV 451 announcements. All suppression features and thresholds SHOULD be 452 configurable. 454 7. Network Stability and Announcement Periodicity 456 To mitigate concerns about stability, all values (except residual 457 bandwidth) MUST NOT be instantaneous measurements. The period to 458 compute statistics, whether rolling average, rolling 98th percentile, 459 or network custom, MUST be a configurable period of time. 460 Announcements MUST also be able to be throttled using configurable 461 inter-update throttle timers. The minimum announcement periodicity 462 is 1 announcement per second. 464 8. Compatibility 466 As per [RFC5305], unrecognized Sub-TLVs should be silently ignored 468 9. Security Considerations 470 This document does not introduce security issues beyond those 471 discussed in [RFC3630] and [RFC5329]. 473 10. IANA Considerations 475 IANA maintains the registry for the sub-TLVs. IS-IS TE Metric 476 Extensions will require one new type code per sub-TLV defined in this 477 document. 479 11. Acknowledgements 481 The authors would like to recognize Ayman Soliman and Les Ginsberg 482 for their contributions. 484 12. References 486 12.1. Normative References 488 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 489 Requirement Levels", BCP 14, RFC 2119, March 1997. 491 [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., 492 and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP 493 Tunnels", RFC 3209, December 2001. 495 [RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering 496 (TE) Extensions to OSPF Version 2", RFC 3630, 497 September 2003. 499 [RFC4203] Kompella, K. and Y. Rekhter, "OSPF Extensions in Support 500 of Generalized Multi-Protocol Label Switching (GMPLS)", 501 RFC 4203, October 2005. 503 [RFC4206] Kompella, K. and Y. Rekhter, "Label Switched Paths (LSP) 504 Hierarchy with Generalized Multi-Protocol Label Switching 505 (GMPLS) Traffic Engineering (TE)", RFC 4206, October 2005. 507 [RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi 508 Topology (MT) Routing in Intermediate System to 509 Intermediate Systems (IS-ISs)", RFC 5120, February 2008. 511 [RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic 512 Engineering", RFC 5305, October 2008. 514 [RFC5316] Chen, M., Zhang, R., and X. Duan, "ISIS Extensions in 515 Support of Inter-Autonomous System (AS) MPLS and GMPLS 516 Traffic Engineering", RFC 5316, December 2008. 518 [RFC5329] Ishiguro, K., Manral, V., Davey, A., and A. Lindem, 519 "Traffic Engineering Extensions to OSPF Version 3", 520 RFC 5329, September 2008. 522 [RFC6119] Harrison, J., Berger, J., and M. Bartlett, "IPv6 Traffic 523 Engineering in IS-IS", RFC 6119, February 2011. 525 [RFC6374] Frost, D. and S. Bryant, "Packet Loss and Delay 526 Measurement for MPLS Networks", RFC 6374, September 2011. 528 12.2. Informative References 530 [I-D.atlas-mpls-te-express-path] 531 Atlas, A., Drake, J., Giacalone, S., Ward, D., Previdi, 532 S., and C. Filsfils, "Performance-based Path Selection for 533 Explicitly Routed LSPs", 534 draft-atlas-mpls-te-express-path-02 (work in progress), 535 February 2013. 537 [I-D.ietf-alto-protocol] 538 Alimi, R., Penno, R., and Y. Yang, "ALTO Protocol", 539 draft-ietf-alto-protocol-13 (work in progress), 540 September 2012. 542 [RFC6375] Frost, D. and S. Bryant, "A Packet Loss and Delay 543 Measurement Profile for MPLS-Based Transport Networks", 544 RFC 6375, September 2011. 546 Authors' Addresses 548 Stefano Previdi (editor) 549 Cisco Systems, Inc. 550 Via Del Serafico 200 551 Rome 00191 552 IT 554 Email: sprevidi@cisco.com 555 Spencer Giacalone 556 Thomson Reuters 557 195 Broadway 558 New York, NY 10007 559 USA 561 Email: Spencer.giacalone@thomsonreuters.com 563 Dave Ward 564 Cisco Systems, Inc. 565 3700 Cisco Way 566 SAN JOSE, CA 95134 567 US 569 Email: wardd@cisco.com 571 John Drake 572 Juniper Networks 573 1194 N. Mathilda Ave. 574 Sunnyvale, CA 94089 575 USA 577 Email: jdrake@juniper.net 579 Alia Atlas 580 Juniper Networks 581 1194 N. Mathilda Ave. 582 Sunnyvale, CA 94089 583 USA 585 Email: akatlas@juniper.net 587 Clarence Filsfils 588 Cisco Systems, Inc. 589 Brussels 590 Belgium 592 Email: cfilsfil@cisco.com