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Litkowski 3 Internet-Draft Orange 4 Intended status: Standards Track A. Simpson 5 Expires: April 28, 2017 Nokia 6 K. Patel 7 Arrcus, Inc 8 J. Haas 9 Juniper Networks 10 L. Yong 11 Huawei 12 October 25, 2016 14 Applying BGP flowspec rules on a specific interface set 15 draft-ietf-idr-flowspec-interfaceset-02 17 Abstract 19 BGP flowspec is an extension to BGP that allows for the dissemination 20 of traffic flow specification rules. The primary application of this 21 extension is DDoS mitigation where the flowspec rules are applied in 22 most cases to all peering routers of the network. 24 This document will present another use case of BGP flowspec where 25 flow specifications are used to maintain some access control lists at 26 network boundary. BGP flowspec is a very efficient distributing 27 machinery that can help in saving OPEX while deploying/updating ACLs. 28 This new application requires flow specification rules to be applied 29 only on a specific subset of interfaces and in a specific direction. 31 The current specification of BGP flowspec ([RFC5575]) introduces the 32 notion of flow specification (which describes the matching criterion) 33 and traffic filtering actions. The flow specification is encoded as 34 part of the NLRI while the traffic filtering actions are encoded as 35 extended communities. The combination of a flow specification and 36 one or more actions is known as a flow specification rule. [RFC5575] 37 does not detail where the flow specification rules need to be 38 applied. 40 Besides the flow specification and traffic filtering actions, this 41 document introduces the notion of traffic filtering scope in order to 42 drive where a particular rule must be applied. In particular, this 43 document introduces the "interface-set" traffic filtering scope that 44 could be used in parallel of traffic filtering actions (marking, 45 rate-limiting ...). The purpose of this extension is to inform 46 remote routers about groups of interfaces where the rule must be 47 applied. 49 This extension can also be used in a DDoS mitigation context where a 50 provider wants to apply the filtering only on specific peers. 52 Requirements Language 54 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 55 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 56 document are to be interpreted as described in [RFC2119]. 58 Status of This Memo 60 This Internet-Draft is submitted in full conformance with the 61 provisions of BCP 78 and BCP 79. 63 Internet-Drafts are working documents of the Internet Engineering 64 Task Force (IETF). Note that other groups may also distribute 65 working documents as Internet-Drafts. The list of current Internet- 66 Drafts is at http://datatracker.ietf.org/drafts/current/. 68 Internet-Drafts are draft documents valid for a maximum of six months 69 and may be updated, replaced, or obsoleted by other documents at any 70 time. It is inappropriate to use Internet-Drafts as reference 71 material or to cite them other than as "work in progress." 73 This Internet-Draft will expire on April 28, 2017. 75 Copyright Notice 77 Copyright (c) 2016 IETF Trust and the persons identified as the 78 document authors. All rights reserved. 80 This document is subject to BCP 78 and the IETF Trust's Legal 81 Provisions Relating to IETF Documents 82 (http://trustee.ietf.org/license-info) in effect on the date of 83 publication of this document. Please review these documents 84 carefully, as they describe your rights and restrictions with respect 85 to this document. Code Components extracted from this document must 86 include Simplified BSD License text as described in Section 4.e of 87 the Trust Legal Provisions and are provided without warranty as 88 described in the Simplified BSD License. 90 Table of Contents 92 1. Use case . . . . . . . . . . . . . . . . . . . . . . . . . . 3 93 1.1. Specific filtering for DDoS . . . . . . . . . . . . . . . 3 94 1.2. ACL maintenance . . . . . . . . . . . . . . . . . . . . . 4 95 2. Collaborative filtering and managing filter direction . . . . 5 96 3. Traffic filtering scope . . . . . . . . . . . . . . . . . . . 6 97 4. Interface specific filtering using BGP flowspec . . . . . . . 7 98 5. Interface-set extended community . . . . . . . . . . . . . . 8 99 6. Handling rules from different sources in the processing pipe 9 100 6.1. Combining Policy Based Routing with BGP flowspec and 101 interface-set . . . . . . . . . . . . . . . . . . . . . . 10 102 6.2. Combining flow collection with BGP flowspec and 103 interface-set . . . . . . . . . . . . . . . . . . . . . . 11 104 7. Scaling of per interface rules . . . . . . . . . . . . . . . 11 105 8. Deployment considerations . . . . . . . . . . . . . . . . . . 12 106 9. Security Considerations . . . . . . . . . . . . . . . . . . . 12 107 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12 108 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 109 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 110 12.1. Normative References . . . . . . . . . . . . . . . . . . 13 111 12.2. Informative References . . . . . . . . . . . . . . . . . 14 112 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 114 1. Use case 116 1.1. Specific filtering for DDoS 118 ----------------- --- (ebgp) - Peer3 (BW 10G) 119 / \/ 120 | /| 121 | PE --- (ebgp) - Transit1(BW 4x10G) 122 Cust1 --- (ebgp) --- PE | 123 | PE ---- (ebgp) - Peer2 (BW 4*10G) 124 | \| 125 Cust2 --- (ebgp) --- PE |----- (ebgp) - Customer3 126 /| | 127 Peer1(BW10G)-(ebgp) | PE --- (ebgp) - Transit2(BW 4x10G) 128 | | 129 \ / 130 ------------------ 132 Figure 1 134 The figure 1 above displays a typical service provider Internet 135 network owing Customers, Peers and Transit. To protect pro actively 136 against some attacks (e.g. DNS, NTP ...), the service provider may 137 want to deploy some rate-limiting of some flows on peers and transit 138 links. But depending on link bandwidth, the provider may want to 139 apply different rate-limiting values. 141 For 4*10G links peer/transit, it may want to apply a rate-limiting of 142 DNS flows of 1G, while on 10G links, the rate-limiting would be set 143 to 250Mbps. Customer interfaces must not be rate-limited. 145 BGP flowspec infrastructure may already be present on the network, 146 and all PEs may have a BGP session running flowspec address family. 147 The flowspec infrastructure may be reused by the service provider to 148 implement such rate-limiting in a very quick manner and being able to 149 adjust values in future quickly without having to configure each node 150 one by one. Using the current BGP flowspec specification, it would 151 not be possible to implement different rate limiter on different 152 interfaces of a same router. The flowspec rule is applied to all 153 interfaces in all directions or on some interfaces where flowspec is 154 activated but flowspec rule set would be the same among all 155 interfaces. 157 Section Section 4 will detail a solution to address this use case 158 using BGP flowspec. 160 1.2. ACL maintenance 162 --------------- --- (ebgp) - Cust4_VPN 163 / \/ 164 Cust1_INT -- (ebgp) --- PE /| 165 | PE ------ (ebgp) - Transit1 166 Cust3_VPN -- (ebgp) --- PE | 167 | PE ------ (ebgp) - Peer2 168 | \| 169 Cust2_INT -- (ebgp) --- PE |----- (ebgp) - Cust4_INT 170 /| | 171 Peer1 ------ (ebgp) -- | PE ------ (ebgp) - Transit2 172 | | 173 \ / 174 ---------------- 176 Figure 2 178 The figure 1 above displays a typical service provider multiservice 179 network owing Customers, Peers and Transit for Internet, as well as 180 VPN services. The service provider requires to ensure security of 181 its infrastructure by applying ACLs at network boundary. Maintaining 182 and deploying ACLs on hundreds/thousands of routers is really painful 183 and time consuming and a service provider would be interested to 184 deploy/updates ACLs using BGP flowspec. In this scenario, depending 185 on the interface type (Internet customer, VPN customer, Peer, Transit 186 ...) the content of the ACL may be different. 188 We foresee two main cases : 190 o Maintaining complete ACLs using flowspec : in this case all the 191 ingress ACL are maintained and deployed using BGPflowspec. See 192 section Section 9 for more details on security aspects. 194 o Requirement of a quick deployment of a new filtering term due to a 195 security alert : new security alerts often requires a fast 196 deployment of new ACL terms. Using traditional CLI and hop by hop 197 provisioning, such deployment takes time and network is 198 unprotected during this time window. Using BGP flowspec to deploy 199 such rule, a service provider can protect its network in few 200 seconds. Then the SP can decide to keep the rule permanently in 201 BGP flowspec or update its ACL or remove the entry (in case 202 equipments are not vulnerable anymore). 204 Section Section 4 will detail a solution to address this use case 205 using BGP flowspec. 207 2. Collaborative filtering and managing filter direction 209 [RFC5575] states in Section 5. : "This mechanism is primarily 210 designed to allow an upstream autonomous system to perform inbound 211 filtering in their ingress routers of traffic that a given downstream 212 AS wishes to drop.". 214 In case of networks collaborating in filtering, there is a use case 215 for performing outbound filtering. Outbound filtering allows to 216 apply traffic action one step before and so may allow to prevent 217 impact like congestions. 219 ---------------------- 220 / \ 221 | Upstream provider | 222 \ / 223 ----------------------- 224 | | 225 |P2 |P1 226 ---------------------- 227 / \ 228 | MyAS | 229 \ / 230 ----------------------- 232 Figure 3 234 In the figure above, MyAS is connected to an upstream provider. If a 235 malicious traffic comes in from the upstream provider, it may 236 congestion P1 or P2 links. If MyAS apply inbound filtering on P1/P2 237 using BGP flowspec, the congestion issue will not be solved. 239 Using collaborative filtering, the upstream provider may propose to 240 MyAS to filter malicious traffic sent to it. We propose to enhance 241 [RFC5575] to make myAS able to send BGP flowspec updates (on eBGP 242 sessions) to the upstream provider to request outbound filtering on 243 peering interfaces towards MyAS. When the upstream provider will 244 receive the BGP flowspec update from MyAS, the BGP flowspec update 245 will contain request for outbound filtering on a specific set of 246 interfaces. The upstream provider will apply automatically the 247 requested filter and congestion will be prevented. 249 3. Traffic filtering scope 251 We see with the use case described above that some BGP flowspec rules 252 may need to be applied only on specific elements of the network 253 (interfaces, nodes ...). The basic specification detailed in 254 [RFC5575] does not address this and does not give any detail on where 255 the traffic filtering rule need to be applied. 257 In addition to the flow specification (flow matching criterion) and 258 traffic filtering actions described in [RFC5575], this document 259 introduces the notion of traffic filtering scope. The traffic 260 filtering scope will describe where a particular flow specification 261 rule must be applied. 263 Using a traffic filtering scope in a BGP flowspec rule is optional. 264 When a rule does not contain any traffic filtering scope parameter, 265 [RFC5575] applies. 267 4. Interface specific filtering using BGP flowspec 269 The use case detailed above requires application of different BGP 270 flowspec rules on different set of interfaces. 272 We propose to introduce, within BGP flowspec, a traffic filtering 273 scope that identifies a group of interfaces where a particular filter 274 should apply on. Identification of interfaces within BGP flowspec 275 will be done through group identifiers. A group identifier marks a 276 set of interfaces sharing a common administrative property. Like a 277 BGP community, the group identifier itself does not have any 278 significance. It is up to the network administrator to associate a 279 particular meaning to a group identifier value (e.g. group ID#1 280 associated to Internet customer interfaces). The group identifier is 281 a local interface property. Any interface may be associated with one 282 or more group identifiers using manual configuration. 284 When a filtering rule advertised through BGP flowspec must be applied 285 only to particular sets of interfaces, the BGP flowspec BGP update 286 will contain the identifiers associated with the relevant sets of 287 interfaces. In addition to the group identifiers, it will also 288 contain the direction the filtering rule must be applied in (see 289 Section 5). 291 Configuration of group identifiers associated to interfaces may 292 change over time. An implementation MUST ensure that the filtering 293 rules (learned from BGP flowspec) applied to a particular interface 294 are always updated when the group identifier mapping is changing. 296 Considering figure 2, we can imagine the following design : 298 o Internet customer interfaces are associated with group-identifier 299 1. 301 o VPN customer interfaces are associated with group-identifier 2. 303 o All customer interfaces are associated with group-identifier 3. 305 o Peer interfaces are associated with group-identifier 4. 307 o Transit interfaces are associated with group-identifier 5. 309 o All external provider interfaces are associated with group- 310 identifier 6. 312 o All interfaces are associated with group-identifier 7. 314 If the service provider wants to deploy a specific inbound filtering 315 on external provider interfaces only, the provider can send the BGP 316 flow specification using group-identifier 6 and including inbound 317 direction. 319 There are some cases where nodes are dedicated to specific functions 320 (Internet peering, Internet Edge, VPN Edge, Service Edge ...), in 321 this kind of scenario, there is an interest for a constrained 322 distribution of filtering rules that are using the interface specific 323 filtering. Without the constrained route distribution, all nodes 324 will received all the filters even if they are not interested in 325 those filters. Constrained route distribution of flowspec filters 326 would allow for a more optimized distribution. 328 5. Interface-set extended community 330 This document proposes a new BGP Route Target extended community 331 called "flowspec interface-set". This document so expands the 332 definition of the Route Target extended community to allow a new 333 value of high order octet (Type field) to be TBD (in addition to the 334 values specified in [RFC4360]). 336 In order to ease intra-AS and inter-AS use cases, this document 337 proposes to have a transitive as well as a non transitive version of 338 this extended community. 340 This new BGP Route Target extended community is encoded as follows : 342 0 1 2 3 343 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 1 344 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 345 | Type (TBD) | 0x02 | Autonomous System Number : 346 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 347 : AS Number (cont.) |O|I| Group Identifier | 348 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 350 The flags are : 352 o O : if set, the flow specification rule MUST be applied in 353 outbound direction to the interface set referenced by the 354 following group-identifier. 356 o I : if set, the flow specification rule MUST be applied in input 357 direction to the interface set referenced by the following group- 358 identifier. 360 Both flags can be set at the same time in the interface-set extended 361 community leading to flow rule to be applied in both directions. An 362 interface-set extended community with both flags set to zero MUST be 363 treated as an error and as consequence, the flowspec update MUST be 364 discarded. As having no direction indicated as no sense, there is no 365 need to propagate the filter informations in the network. 367 The Group Identifier is coded as a 14-bit number (values goes from 0 368 to 16383). 370 Multiple instances of the interface-set community may be present in a 371 BGP update. This may appear if the flow rule need to be applied to 372 multiple set of interfaces. 374 Multiple instances of the community in a BGP update MUST be 375 interpreted as a "OR" operation : if a BGP update contains two 376 interface-set communities with group ID 1 and group ID 2, the filter 377 would need to be installed on interfaces belonging to Group ID 1 or 378 Group ID 2. 380 As using a Route Target, route distribution of flowspec NLRI with 381 interface-set may be subject to constrained distribution as defined 382 in [RFC4684]. Constrained route distribution for flowspec routes 383 using interface-set requires discussion and will be addressed in a 384 future revision of the document. 386 6. Handling rules from different sources in the processing pipe 388 A packet on a router may be processed by multiple rules that are 389 originated by different sources (e.g. statically configured, I2RS 390 ephemeral, BGP ephemeral ...). [RFC5575] does not provide any 391 guidance regarding the precedence of BGP flowspec rules compared to 392 other sources. A new version of BGP flowspec 393 [I-D.hares-idr-flowspec-v2] should address these precedence rules 394 definition in future. 396 This document only addresses the usage of "interface-set" in the 397 framework of [RFC5575] and the following generic rules SHOULD be used 398 by an implementation: 400 o An inbound flowspec rule using interface-set SHOULD be processed 401 after all existing inbound traffic processing rules (ACL, PBR, 402 QoS, flow collection ...) and SHOULD be applied before forwarding 403 decision is made. 405 o An outbound flowspec rule using interface-set SHOULD be processed 406 after all existing outbound traffic processing rules (ACL, PBR, 407 QoS, flow collection ...) and SHOULD be applied after forwarding 408 decision has been made. 410 Inbound processing Forwarding Outbound processing 411 ACL->PBR->BGP_FS in -> Lookup -> PBR->QoS->I2RS->BGP_FS out 413 Example of packet processing pipe 415 In the example above, any BGP flowspec rule ([RFC5575]) with an 416 inbound interface-set is processed after all existing features (ACL, 417 PBR and QoS) but before the lookup is done. The outbound BGP 418 flowspec rules with interface-set are applied after the lookup and 419 after all any existing feature. 421 This section gives two examples of combining existing features with 422 BGP flowspec+interface-set attribute on an interface. 424 6.1. Combining Policy Based Routing with BGP flowspec and interface-set 426 In this example, a router has an already configured inbound policy on 427 an interface IF1 with the following rules: 429 o Static policy IN: 431 * Entry 1: from udp 10/8 to 11/8 port 53 then set dscp af11 and 432 accept 434 * Entry 2: from tcp 10/8 to 11/8 port 22 then set dscp af22 and 435 accept 437 * Entry 3: from tcp 10/8 to 11/8 port 80 then set dscp af11 and 438 accept 440 * Entry 4: from ip 10/8 to 11/8 then drop 442 In addition to this static inbound ACL, the router receives the 443 following unordered BGP flowspec version 1 rules with an interface- 444 set matching IF1. 446 o flowspec rules IN : 448 * from udp 10.0.0.1/32 to 11/8 port 53 then drop 450 * from tcp 10/8 to 11/8 port 80 then set dscp af32 and accept 452 * from udp 10/8 to 11/8 then accept 454 The combination of the static inbound ACL and the inbound "interface- 455 set" flowspec rules should result in the following packet processing: 457 o a UDP flow from 10.0.0.1 to 11.0.0.2 on port 53 will be rejected: 458 firstly, it is allowed by the static ACL and DSCP is set to af11 459 but then it is dropped by the flowspec filter. 461 o a UDP flow from 10.0.0.2 to 11.0.0.2 on port 53 will be accepted 462 and DSCP will be set to af11. 464 o a TCP flow from 10.0.0.2 to 11.0.0.2 on port 80 will be accepted 465 and DSCP will be set to af32: firstly, the static PBR rule set the 466 DSCP to af11 and accepts the packet, then the flowspec filter 467 rewrites the DSCP to af32 and accepts it also. 469 6.2. Combining flow collection with BGP flowspec and interface-set 471 A router may activate flow collection features (used in collaboration 472 with Netflow export). Flow collection can be done at input side or 473 output side. When a router is configured to collect flow 474 informations on an inbound interface, the flow collection happens 475 before any BGP flowspec rule with interface-set: if a particular 476 packet flow is denied by a BGP flowspec rule, it will still be 477 collected. 479 The same happens if a router is configured to collect flow 480 informations on an outbound interface, the flow collection happens, 481 and then the BGP flowspec rule is applied: the flow is collected 482 whatever the result of the BGP flowspec rule. 484 7. Scaling of per interface rules 486 Without "interface-set", all the interfaces are using the same 487 flowspec filter, while with "interface-set" different interfaces may 488 have different flowspec filters (with different terms and actions). 489 Having such flowspec rules that are applied on specific interfaces 490 may create forwarding instructions that may be harder to share within 491 the forwarding plane: a particular term may be present or not in the 492 filter of a particular interface. 494 An implementation SHOULD take care about trying to keep sharing 495 forwarding structures as much as possible in order to limit the 496 scaling impact. How the implementation would do so is out of scope 497 of the document. 499 8. Deployment considerations 501 There are some cases where a particular BGP flowspec NLRI may be 502 advertised to different interface groups with a different action. 503 For example, a service provider may want to discard all ICMP traffic 504 from customer interfaces to infrastructure addresses and want to 505 rate-limit the same traffic when it comes from some internal 506 platforms. These particular cases require ADD-PATH to be deployed in 507 order to ensure that all paths (NLRI+interface-set group-id+actions) 508 are propagated within the BGP control plane. Without ADD-PATH, only 509 a single "NLRI+interface-set group-id+actions" will be propagated, so 510 some filtering rules will never be applied. 512 9. Security Considerations 514 Managing permanent Access Control List by using BGP flowspec as 515 described in Section 1.2 helps in saving roll out time of such ACL. 516 However some ACL especially at network boundary are critical for the 517 network security and loosing the ACL configuration may lead to 518 network open for attackers. 520 By design, BGP flowspec rules are ephemeral : the flow rule exists in 521 the router while the BGP session is UP and the BGP path for the rule 522 is valid. We can imagine a scenario where a Service Provider is 523 managing the network boundary ACLs by using only flowspec. In this 524 scenario, if , for example, an attacker succeed to make the internal 525 BGP session of a router to be down , it can open all boundary ACLs on 526 the node, as flowspec rules will disappear due to the BGP session 527 down. 529 In reality, the chance for such attack to occur is low, as boundary 530 ACLs should protect the BGP session from being attacked. 532 In order to complement the BGP flowspec solution is such deployment 533 scenario and provides security against such attack, a service 534 provider may activate Long lived Graceful Restart 535 [I-D.uttaro-idr-bgp-persistence] on the BGP session owning flowspec 536 address family. So in case of BGP session to be down, the BGP paths 537 of flowspec rules would be retained and the flowspec action will be 538 retained. 540 10. Acknowledgements 542 Authors would like to thanks Wim Hendrickx and Robert Raszuk for 543 their valuable comments. 545 11. IANA Considerations 547 This document requests a new type from the "BGP Transitive Extended 548 Community Types" extended community registry. This type name shall 549 be 'FlowSpec'. 551 This document requests a new type from the "BGP Non-Transitive 552 Extended Community Types" extended community registry. This type 553 name shall be 'FlowSpec'. 555 This document requests creation of a new registry called "FlowSpec 556 Extended Community Sub-Types". This registry contains values of the 557 second octet (the "Sub-Type" field) of an extended community when the 558 value of the first octet (the "Type" field) is to one of those 559 allocated in this document. 561 Within this new registry, this document requests a new subtype 562 (suggested value 0x02), this sub-type shall be named "interface-set". 564 12. References 566 12.1. Normative References 568 [I-D.ietf-idr-rtc-no-rt] 569 Rosen, E., Patel, K., Haas, J., and R. Raszuk, "Route 570 Target Constrained Distribution of Routes with no Route 571 Targets", draft-ietf-idr-rtc-no-rt-05 (work in progress), 572 May 2016. 574 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 575 Requirement Levels", BCP 14, RFC 2119, 576 DOI 10.17487/RFC2119, March 1997, 577 . 579 [RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended 580 Communities Attribute", RFC 4360, DOI 10.17487/RFC4360, 581 February 2006, . 583 [RFC4684] Marques, P., Bonica, R., Fang, L., Martini, L., Raszuk, 584 R., Patel, K., and J. Guichard, "Constrained Route 585 Distribution for Border Gateway Protocol/MultiProtocol 586 Label Switching (BGP/MPLS) Internet Protocol (IP) Virtual 587 Private Networks (VPNs)", RFC 4684, DOI 10.17487/RFC4684, 588 November 2006, . 590 [RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J., 591 and D. McPherson, "Dissemination of Flow Specification 592 Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009, 593 . 595 12.2. Informative References 597 [I-D.hares-idr-flowspec-v2] 598 Hares, S., "BGP Flow Specification Version 2", draft- 599 hares-idr-flowspec-v2-00 (work in progress), June 2016. 601 [I-D.uttaro-idr-bgp-persistence] 602 Uttaro, J., Chen, E., Decraene, B., and J. Scudder, 603 "Support for Long-lived BGP Graceful Restart", draft- 604 uttaro-idr-bgp-persistence-03 (work in progress), November 605 2013. 607 Authors' Addresses 609 Stephane Litkowski 610 Orange 612 Email: stephane.litkowski@orange.com 614 Adam Simpson 615 Nokia 617 Email: adam.simpson@nokia.com 619 Keyur Patel 620 Arrcus, Inc 622 Email: keyur@arrcus.com 624 Jeff Haas 625 Juniper Networks 627 Email: jhaas@juniper.net 629 Lucy Yong 630 Huawei 632 Email: lucy.yong@huawei.com