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Checking references for intended status: Informational ---------------------------------------------------------------------------- == Outdated reference: A later version (-06) exists of draft-shirasaki-nat444-02 Summary: 0 errors (**), 0 flaws (~~), 2 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group C. Donley, Ed. 3 Internet-Draft CableLabs 4 Intended status: Informational L. Howard 5 Expires: April 5, 2013 Time Warner Cable 6 V. Kuarsingh 7 Rogers Communications 8 J. Berg 9 CableLabs 10 J. Doshi 11 University of Colorado 12 October 2, 2012 14 Assessing the Impact of Carrier-Grade NAT on Network Applications 15 draft-donley-nat444-impacts-05 17 Abstract 19 NAT444 is an IPv4 extension technology being considered by Service 20 Providers to continue offering IPv4 service to customers while 21 transitioning to IPv6. This technology adds an extra Carrier-Grade 22 NAT ("CGN") in the Service Provider network, often resulting in two 23 NATs. CableLabs, Time Warner Cable, and Rogers Communications 24 independently tested the impacts of NAT444 on many popular Internet 25 services using a variety of test scenarios, network topologies, and 26 vendor equipment. This document identifies areas where adding a 27 second layer of NAT disrupts the communication channel for common 28 Internet applications. This document was updated to also include 29 Dual-Stack Lite impacts. 31 Status of this Memo 33 This Internet-Draft is submitted in full conformance with the 34 provisions of BCP 78 and BCP 79. 36 Internet-Drafts are working documents of the Internet Engineering 37 Task Force (IETF). Note that other groups may also distribute 38 working documents as Internet-Drafts. The list of current Internet- 39 Drafts is at http://datatracker.ietf.org/drafts/current/. 41 Internet-Drafts are draft documents valid for a maximum of six months 42 and may be updated, replaced, or obsoleted by other documents at any 43 time. It is inappropriate to use Internet-Drafts as reference 44 material or to cite them other than as "work in progress." 46 This Internet-Draft will expire on April 5, 2013. 48 Copyright Notice 49 Copyright (c) 2012 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 . . . . . . . . . . . . . . . . . . . . . . . . . 4 65 2. Testing Scope . . . . . . . . . . . . . . . . . . . . . . . . 5 66 2.1. Test Cases . . . . . . . . . . . . . . . . . . . . . . . . 5 67 2.1.1. Case1: Single Client, Single Home Network, Single 68 Service Provider . . . . . . . . . . . . . . . . . . . 5 69 2.1.2. Case2: Two Clients, Single Home Network, Single 70 Service Provider . . . . . . . . . . . . . . . . . . . 6 71 2.1.3. Case3: Two Clients, Two Home Networks, Single 72 Service Provider . . . . . . . . . . . . . . . . . . . 7 73 2.1.4. Case4: Two Clients, Two Home Networks, Two Service 74 Providers Cross ISP . . . . . . . . . . . . . . . . . 8 75 2.2. General Test Environment . . . . . . . . . . . . . . . . . 8 76 2.3. Test Metrics . . . . . . . . . . . . . . . . . . . . . . . 10 77 2.4. Test Scenarios Executed . . . . . . . . . . . . . . . . . 11 78 2.5. General Test Methodologies . . . . . . . . . . . . . . . . 11 79 3. Observed CGN Impacts . . . . . . . . . . . . . . . . . . . . . 12 80 3.1. Dropped Services . . . . . . . . . . . . . . . . . . . . . 12 81 3.2. Performance Impacted Services . . . . . . . . . . . . . . 14 82 3.3. Improvements since 2010 . . . . . . . . . . . . . . . . . 15 83 3.4. Additional CGN Challenges . . . . . . . . . . . . . . . . 15 84 4. 2011 Summary of Results . . . . . . . . . . . . . . . . . . . 16 85 4.1. NAT444 . . . . . . . . . . . . . . . . . . . . . . . . . . 17 86 4.2. DS-Lite . . . . . . . . . . . . . . . . . . . . . . . . . 19 87 5. 2010 Summary of Results . . . . . . . . . . . . . . . . . . . 21 88 5.1. Case1: Single Client, Single Home Network, Single 89 Service Provider . . . . . . . . . . . . . . . . . . . . . 22 90 5.2. Case2: Two Clients, Single Home Network, Single 91 Service Provider . . . . . . . . . . . . . . . . . . . . . 24 92 5.3. Case3: Two Clients, Two Home Networks, Single Service 93 Provider . . . . . . . . . . . . . . . . . . . . . . . . . 24 94 5.4. Case4: Two Clients, Two Home Networks, Two Service 95 Providers Cross ISP . . . . . . . . . . . . . . . . . . . 25 97 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25 98 7. Security Considerations . . . . . . . . . . . . . . . . . . . 25 99 8. Informative References . . . . . . . . . . . . . . . . . . . . 25 100 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 26 101 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 26 103 1. Introduction 105 IANA, APNIC, and RIPE exhausted their IPv4 address space in 2011- 106 2012. Current projections suggest that ARIN may exhaust its free 107 pool of IPv4 addresses in 2013. IPv6 is the solution to the IPv4 108 depletion problem; however, the transition to IPv6 will not be 109 completed prior to IPv4 exhaustion. NAT444 [I-D.shirasaki-nat444] 110 and Dual-Stack Lite ([RFC6333]) are transition mechanisms that will 111 allow Service Providers to multiplex customers behind a single IPv4 112 address, which will allow many legacy devices and applications some 113 IPv4 connectivity. While both NAT444 and Dual-Stack Lite do provide 114 basic IPv4 connectivity, they impact a number of advanced 115 applications. This document describes suboptimal behaviors of NAT444 116 and DS-Lite in our test environments. 118 In July-August 2010, CableLabs, Time Warner Cable, and Rogers 119 Communications tested the impact of NAT444 on common applications 120 using Carrier Grade NAT (CGN) devices. This testing was focused on a 121 wide array of real time usage scenarios designed to evaluate the user 122 experience over the public Internet using NAT444, in both single ISP 123 and dual ISP environments. The purpose of this testing was to 124 identify applications where the technology either breaks or 125 significantly impacts the user experience. The outcome of the 126 testing revealed that applications such as video streaming, video 127 gaming and peer-to-peer file sharing are impacted by NAT444. 129 From June - October 2011, CableLabs conducted additional testing of 130 CGN technologies, including both NAT444 and Dual-Stack Lite. The 131 testing focused on working with several vendors including A10, 132 Alcatel-Lucent, and Juniper to optimize the performance of those 133 applications that experienced negative impacts during earlier CGN 134 testing and to expand the testing to DS-Lite. 136 Applications that were tested included but were not necessarily 137 limited to the following: 139 1. Video/Audio streaming, e.g. Silverlight-based applications, 140 Netflix, YouTube, Pandora 2. 142 2. Peer-to-peer applications, e.g. video gaming, uTorrent 144 3. On line gaming, e.g. Xbox 146 4. Large file transfers using File Transfer Protocol (FTP) 148 5. Session Initiation Protocol (SIP) calls via X-Lite, Skype 149 6. Social Networking, e.g. Facebook, Webkinz 151 7. Video chat, e.g. Skype 153 8. Web conferencing 155 2. Testing Scope 157 2.1. Test Cases 159 The diagrams below depict the general network architecture used for 160 testing NAT444 and Dual Stack-Lite co-existence technologies at 161 CableLabs. 163 2.1.1. Case1: Single Client, Single Home Network, Single Service 164 Provider 166 ^^^^^^^^ 167 (Internet) 168 vvvvvvvv 169 | 170 | 171 +---------------+ 172 | CGN | 173 +---------------+ 174 | 175 +---------------+ 176 | CMTS | 177 +---------------+ 178 | 179 +---------------+ 180 | CM | 181 +---------------+ 182 | 183 +-------------------------+ 184 | Home Router | 185 +-------------------------+ 186 | 187 +---------------+ 188 | Client | 189 +---------------+ 191 This is a typical case for a client accessing content on the 192 Internet. For this case, we focused on basic web browsing, voice and 193 video chat, instant messaging, video streaming (using YouTube, Google 194 Videos , etc.), Torrent leeching and seeding, FTP, and gaming. 196 2.1.2. Case2: Two Clients, Single Home Network, Single Service Provider 198 ^^^^^^^^ 199 (Internet) 200 vvvvvvvv 201 | 202 | 203 +---------------+ 204 | CGN | 205 +---------------+ 206 | 207 +---------------+ 208 | CMTS | 209 +---------------+ 210 | 211 +---------------+ 212 | CM | 213 +---------------+ 214 | 215 +-------------------------+ 216 | Home Router | 217 +-------------------------+ 218 | | 219 +---------------+ +---------------+ 220 | Client | | Client | 221 +---------------+ +---------------+ 223 This is similar to Case 1, except that two clients are behind the 224 same LSN and in the same home network. This test case was conducted 225 to observe any change in speed in basic web browsing and video 226 streaming. 228 2.1.3. Case3: Two Clients, Two Home Networks, Single Service Provider 230 ^^^^^^^^ 231 (Internet) 232 vvvvvvvv 233 | 234 | 235 +---------------+ 236 | CGN | 237 +---------------+ 238 | 239 +---------------+ 240 | CMTS | 241 +---------------+ 242 | 243 ---------------------------------------- 244 | | 245 +---------------+ +---------------+ 246 | CM | | CM | 247 +---------------+ +---------------+ 248 | | 249 +-------------------------+ +-------------------------+ 250 | Home Router | | Home Router | 251 +-------------------------+ +-------------------------+ 252 | | 253 +---------------+ +---------------+ 254 | Client | | Client | 255 +---------------+ +---------------+ 257 In this scenario, the two clients are under the same LSN but behind 258 two different gateways. This simulates connectivity between two 259 residential subscribers on the same ISP. We tested peer-to-peer 260 applications. 262 2.1.4. Case4: Two Clients, Two Home Networks, Two Service Providers 263 Cross ISP 265 ^^^^^^^^ ^^^^^^^^ 266 ( ISP A ) ( ISP B ) 267 Vvvvvvvv vvvvvvvv 268 | | 269 +---------------+ +---------------+ 270 | LSN | | LSN | 271 +---------------+ +---------------+ 272 | | 273 +---------------+ +---------------+ 274 | CMTS | | CMTS | 275 +---------------+ +---------------+ 276 | | 277 +---------------+ +---------------+ 278 | CM | | CM | 279 +---------------+ +---------------+ 280 | | 281 +-------------------------+ +-------------------------+ 282 | Home Router | | Home Router | 283 +-------------------------+ +-------------------------+ 284 | | 285 +---------------+ +---------------+ 286 | Client | | Client | 287 +---------------+ +---------------+ 289 This test case is similar to Case 1 but with the addition of another 290 identical ISP. This topology allows us to test traffic between two 291 residential customers connected across the Internet. We focused on 292 client-to-client applications such as IM and peer-to-peer. 294 2.2. General Test Environment 296 The lab environment was intended to emulate multiple service provider 297 networks with a CGN deployed, and with connectivity to the public 298 IPv4 or IPv6 internet (as dictated by the co-existence technology 299 under test). This was accomplished by configuring a CGN behind 300 multiple CMTSes and setting up multiple home networks for each ISP. 301 Testing involved sending traffic to and from the public internet in 302 both single and dual ISP environments, using both single and multiple 303 home networks. The following equipment was used for testing: 305 o CGN 307 o CMTS 308 o IP sniffer 310 o RF sniffer 312 o Metrics tools (for network performance) 314 o CPE gateway devices 316 o Laptop or desktop computers (multiple OS used) 318 o Gaming consoles 320 o iPad or tablet devices 322 o other CE equipment, e.g. BluRay players supporting miscellaneous 323 applications 325 One or more CPE gateway devices were configured in the home network. 326 One or more host devices behind the gateways were also configured in 327 order to test conditions such as multiple users on multiple home 328 networks in the CGN architecture, both in single and dual ISP 329 environments. 331 The scope of testing was honed down to the specific types of 332 applications and network conditions that demonstrated a high 333 probability of diminishing user experience based on prior testing. 334 The following use cases were tested: 336 1. Video streaming over Netflix 338 2. Video streaming over YouTube 340 3. Video streaming over Joost 342 4. On line gaming with Xbox (one user) 344 5. Peer to Peer gaming with Xbox (two users) 346 6. Bit Torrent/uTorrent file seeding/leeching 348 7. Pandora internet radio 350 8. FTP server 352 9. Web conferencing (GTM, WebEx) 354 10. Social Networking - Facebook, Webkinz (chat, YouTube, file 355 transfer) 357 11. Internet Archive - Video and Audio streaming; large file 358 downloads 360 12. Video streaming using iClips 362 13. SIP Calls - X-Lite, Skype, PJSIP 364 14. MS Smooth Streaming (Silverlight) 366 15. Video chat - Skype, OoVoo 368 The following CPE devices were used for testing these applications on 369 one or more home networks: 371 1. Windows 7, XP and Vista based laptops 373 2. MAC OS X laptop 375 3. iPad 377 4. Xbox gaming consoles 379 5. iPhone and Android smartphones 381 6. LG Blu-Ray player (test applications such as Netflix, Vudu, etc.) 383 7. Home routers - Netgear, Linksys, D-Link, Cisco, Apple 385 2.3. Test Metrics 387 Metrics data that were collected during the course of testing were 388 related to throughput, latency, and jitter. These metrics were 389 evaluated under three conditions: 391 1. Initial finding on the CGN configuration used for testing 393 2. Retest of the same test scenario with the CGN removed from the 394 network 396 3. Retest with a new configuration (optimized) on the CGN (when 397 possible) 399 In our testing, we found no significant differences with respect to 400 latency or jitter when the CGN was in the network versus when it was 401 not present in the network. It should be noted that we did not 402 conduct any performance testing and metrics gathered were limited to 403 single session scenarios. Also, bandwidth was not restricted on the 404 DOCSIS network. Simulated homes shared a single DOCSIS upstream and 405 downstream channel. 407 Note: Performance testing as defined by CableLabs includes load 408 testing, induction of impairments on the network, etc. This type of 409 testing was out of scope for CGN testing. 411 2.4. Test Scenarios Executed 413 The following test scenarios were executed using the aforementioned 414 applications and test equipment: 416 1. Single ISP, Single Home Network with Single User 418 2. Single ISP, Two Home Networks With One User on Each Network 420 3. Dual ISPs, Single Home Network with Single User on each ISP 422 4. Dual ISPs, One Home Network With One User ISP-A; Two Home 423 Networks with one user on each for ISP-B 425 These test scenarios were executed for both NAT444 and DS-Lite 426 technologies. 428 2.5. General Test Methodologies 430 The CGN was configured for optimal setting for the specific test 431 being executed for NAT444 or DS-Lite. Individual vendors provided 432 validation of the configuration used for the co-existence technology 433 under test prior to the start of testing. Some NAT444 testing used 434 private [RFC1918] IPv4 space between the CGN and CPE router; other 435 tests used public (non-[RFC1918]) IPv4 space between the CGN and CPE 436 router. With the exception of 6to4 ([RFC3056]) traffic, we observed 437 no difference in test results whether private or public address space 438 was used. 6to4 failed when public space was used between the CGN and 439 CPE router was public, but CPE routers did not initiate 6to4 when 440 private space was used. 442 CPE gateways and client devices were configured with IPv4 or IPv6 443 addresses using DHCP or manual configuration as required by each of 444 the devices used in the test. 446 All devices were brought to operational state. Connectivity of CPE 447 devices to provider network and public Internet were verified prior 448 to start of each test. 450 IP sniffers and metrics tools were configured as required before 451 starting tests. IP capture and metrics data was collected for all 452 failed test scenarios. Sniffing was configured behind the home 453 routers, north and south of the CMTS, and north and south of the CGN. 455 The test technician executed test scenarios listed above, for single 456 and dual ISP environments, testing multiple users on multiple home 457 networks, using the applications described above, where applicable to 458 the each specific test scenario. Results checklists were compiled 459 for all tests executed and for each combination of devices tested. 461 3. Observed CGN Impacts 463 CGN testing revealed that basic services such as e-mail and web 464 browsing worked normally and as expected. However, there were some 465 service affecting issues noted for applications that fall into two 466 categories; dropped service and performance impacted service. In 467 addition, for some specific applications in which the performance was 468 impacted, throughput, latency and jitter measurements were taken. We 469 observed that performance often differs from vendor to vendor and 470 from test environment to test environment, and the results are 471 somewhat difficult to predict. So as to not become a comparison 472 between different vendor implementations, these results are presented 473 in summary form. When issues were identified, we worked with the 474 vendors involved to confirm the specific issues and explore 475 workarounds. Except where noted, impacts to NAT444 and DS-Lite were 476 similar. 478 In 2010 testing, we identified that IPv6 transition technologies such 479 as 6to4 [RFC3056] and Teredo [RFC4380]) fail outright or are subject 480 to severe service degradation. We did not repeat transition 481 technology testing in 2011. 483 Note: While e-mail and web browsing operated as expected within our 484 environment, there have been reports that anti-spam/anti-abuse 485 measures limiting the number of connections from a single address can 486 cause problems in a CGN environment by improperly interpreting 487 address sharing as too many connections from a single device. Care 488 should be taken when deploying CGN to mitigate the impact of address 489 sharing when configuring anti-spam/anti-abuse measures. See Section 490 3.4. 492 3.1. Dropped Services 494 Several peer-to-peer applications, specifically peer-to-peer gaming 495 using Xbox and peer-to-peer SIP calls using the PJSIP client, failed 496 in both the NAT444 and Dual-Stack Lite environments. Many CGN 497 devices use "full cone" NAT so that once the CGN maps a port for 498 outbound services, it will accept incoming connections to that port. 499 However, some applications did not first send outgoing traffic and 500 hence did not open an incoming port through the CGN. Other 501 applications try to open a particular fixed port through the CGN; 502 while service will work for a single subscriber behind the CGN, it 503 fails when multiple subscribers try to use that port. 505 PJSIP and other SIP software worked when clients used a registration 506 server to initiate calls, provided that the client inside the CGN 507 initiated the traffic first and that only one SIP user was active 508 behind a single IPv4 address at any given time. However, in our 509 testing, we observed that when making a direct client-to-client SIP 510 call across two home networks on a single ISP, or when calling from a 511 single home network across dual ISPs, calls could neither be 512 initiated nor received. 514 In the case of peer-to-peer gaming between two Xbox 360 users in 515 different home networks on the same ISP, the game could not be 516 connected between the two users. Both users shared an outside IP 517 address, and tried to connect to the same port, causing a connection 518 failure. There are some interesting nuances to this problem. In the 519 case where two users are in the same home network and the scenario is 520 through a single ISP, when the Xbox tries to register with the Xbox 521 server, the server sees that both Xboxes are coming through the same 522 public IP address and directs the devices to connect using their 523 internal IP addresses. So, the connection ultimately gets 524 established directly between both Xboxes via the home gateway, rather 525 than the Xbox server. In the case where there are two Xbox users on 526 two different home networks using a single ISP, and the CGN is 527 configured with only one public IPv4 address, this scenario will not 528 work because the route between the two users cannot be determined. 529 However, if the CGN is configured with two public NAT IP addresses 530 this scenario will work because now there is a unique IP address to 531 communicate with. This is not an ideal solution, however, because it 532 means that there is a one-to-one relationship between IP addresses in 533 the public NAT and the number of Xbox users on each network. 535 Update: in December, 2011, Microsoft released an update for Xbox. 536 While we did not conduct thorough testing using the new release, 537 preliminary testing indicates that Xboxes that upgraded to the latest 538 version can play head-to-head behind a CGN, at least for some games. 540 Other peer-to-peer applications that were noted to fail were seeding 541 sessions initiated on Bittorent and uTorrent. In our test, torrent 542 seeding was initiated on a client inside the CGN. Leeching was 543 initiated using a client on the public Internet. It was observed 544 that direct peer-to-peer seeding did not work. However, the torrent 545 session typically redirected the leeching client to a proxy server, 546 in which case the torrent session was set up successfully. 547 Additionally, with the proxy in the network, re-seeding via 548 additional leech clients worked as would be expected for a typical 549 torrent session. Finally, uTorrent tries to use STUN to identify its 550 outside address. In working with vendors, we learned that increasing 551 the STUN timeout to 4 minutes improved uTorrent seeding performance 552 behind a CGN, resulting in the ability for the uTorrent client to 553 open a port and successfully seed content. 555 3.2. Performance Impacted Services 557 Large size file transfers and multiple video streaming sessions 558 initiated on a single client on the same home network behind the CGN 559 experienced reduced performance in our environment. We measured 560 these variations in user experience against a baseline IPv4 561 environment where NAT is not deployed. 563 In our testing, we tried large file transfers from several FTP sites, 564 as well as downloading sizable audio and video files (750MB - 1.4 GB) 565 from the Internet Archive. We observed that when Dual-Stack Lite was 566 implemented for some specific home router and client combinations, 567 the transfer rate was markedly slower. For example, PC1 using one 568 operating system behind the same home router as PC2 using a different 569 operating system yielded a transfer rate of 120Kbps for PC1, versus 570 250Kbps for PC2. Our conclusion is that varying combinations of home 571 routers and CE client devices may result in a user experience that is 572 less than what the user would expect for typical applications. It is 573 also difficult to predict which combinations of CPE routers and CE 574 devices will produce a reduced experience for the user. We did not 575 analyze the root cause of the divergence in performance across CE 576 devices, as this was beyond the scope of our testing. However, as 577 this issue was specific to Dual-Stack Lite, we suspect that it is 578 related to the MTU. 580 While video streaming sessions for a single user generally performed 581 well, testing revealed that video streaming sessions such as 582 Microsoft Smooth Streaming technology (i.e. Silverlight) or Netflix 583 might also exhibit some service impacting behavior. In particular, 584 this was observed on one older, yet popular and well-known CPE router 585 where the first session was severely degraded when a second session 586 was initiated in the same home network. Traffic from the first 587 session ceased for 8 s once the second session was initiated. While 588 we are tempted to write this off as a problematic home router, its 589 popularity suggests that home router interactions may cause issues in 590 NAT444 deployments (newer routers that support DS-Lite were not 591 observed to experience this condition). Overall, longer buffering 592 times for video sessions were noted for most client devices behind 593 all types of home routers. However, once the initial buffering was 594 complete, the video streams were consistently smooth. In addition, 595 there were varying degrees as to how well multiple video sessions 596 were displayed on various client devices across the CPE routers 597 tested. Some video playback devices performed better than others. 599 3.3. Improvements since 2010 601 Since CableLabs completed initial CGN testing in 2010, there have 602 been quantifiable improvements in performance over CGN since that 603 time. These improvements may be categorized as follows: 605 o Content provider updates 607 o Application updates 609 o Improvements on the CGNs themselves 611 In terms of content provider updates, we have noted improvements in 612 the overall performance of streaming applications in the CGN 613 environment. Whereas applications such as streaming video were very 614 problematic a year ago with regard to jitter and latency, our most 615 recent testing revealed that there is less of an issue with these 616 conditions, except in some cases when multiple video streaming 617 sessions were initiated on the same client using specific types of 618 home routers. Applications such as MS Smooth Streaming appear to 619 have addressed these issues to some degree. 621 As far as application updates, use of STUN and/or proxy servers to 622 offset some of the limitations of NAT and tunneling in the network 623 are more evident as workarounds to the peer-to-peer issues. 624 Applications appear to have incorporated other mechanisms for 625 delivering content faster, even if buffering times are somewhat 626 slower and the content is not rendered as quickly. 628 CGN vendors have also upgraded their devices to mitigate several 629 known issues with specific applications. With regard to addressing 630 peer-to-peer SIP call applications, port reservations appear to be a 631 workaround to the problem. However, this approach has limitations 632 because of there are limited numbers of users that can have port 633 reservations at any given time. For example, one CGN implementation 634 allowed a port reservation to be made on port 5060 (default SIP port) 635 but this was the only port that could be configured for the SIP 636 client. This means that only one user can be granted the port 637 reservation. 639 3.4. Additional CGN Challenges 641 There are other challenges that arise when using shared IPv4 address 642 space, as with NAT444. Some of these challenges include: 644 o Loss of geolocation information - Often, translation zones will 645 cross traditional geographic boundaries. Since the source 646 addresses of packets traversing an LSN are set to the external 647 address of the LSN, it is difficult for external entities to 648 associate IP/Port information to specific locations/areas. 650 o Lawful Intercept/Abuse Response - Due to the nature of NAT444 651 address sharing, it will be hard to determine the customer/ 652 endpoint responsible for initiating a specific IPv4 flow based on 653 source IP address alone. Content providers, service providers, 654 and law enforcement agencies will need to use new mechanisms 655 (e.g., logging source port and timestamp in addition to source IP 656 address) to potentially mitigate this new problem. This may 657 impact the timely response to various identification requests. 658 See [RFC6269]. 660 o Antispoofing - Multiplexing users behind a single IP address can 661 lead to situations where traffic from that address triggers 662 antispoofing/DDoS protection mechanisms, resulting in 663 unintentional loss of connectivity for some users. We have 664 received reports of such antispoofing/DDoS mechanisms affecting 665 email and web services in some instances, but did not experience 666 them in our environment. 668 4. 2011 Summary of Results 669 4.1. NAT444 671 +--------------+--------+--------+--------+--------------+----------+ 672 | Test | Single | Single | Dual | Dual ISP, | Notes | 673 | Scenario | ISP, | ISP, | ISP, | One HN+One | | 674 | (per Test | Single | Two | One HN | User on | | 675 | Plan) | HN, | HN, | with | ISP-A, Two | | 676 | | Single | Single | One | HN with One | | 677 | | User | User | User | User on Each | | 678 | | | on | on | on ISP-B | | 679 | | | Each | Each | | | 680 | | | | ISP | | | 681 +--------------+--------+--------+--------+--------------+----------+ 682 | Video | Pass | Pass | Pass | Pass | fails | 683 | streaming | | | | | behind | 684 | over Netflix | | | | | one | 685 | | | | | | router | 686 +--------------+--------+--------+--------+--------------+----------+ 687 | Video | Pass | Pass | Pass | Pass | | 688 | streaming | | | | | | 689 | over YouTube | | | | | | 690 +--------------+--------+--------+--------+--------------+----------+ 691 | Video | Pass | Pass | Pass | Pass | | 692 | streaming | | | | | | 693 | over Joost | | | | | | 694 +--------------+--------+--------+--------+--------------+----------+ 695 | Online | Pass | Pass | Pass | NT | | 696 | gaming with | | | | | | 697 | one user | | | | | | 698 +--------------+--------+--------+--------+--------------+----------+ 699 | Peer to Peer | Pass | Fail | Pass | NT | fails | 700 | gaming with | | | | | when | 701 | two users | | | | | both | 702 | | | | | | users | 703 | | | | | | NAT to | 704 | | | | | | same | 705 | | | | | | address | 706 +--------------+--------+--------+--------+--------------+----------+ 707 | Bit Torrent | Fail | Fail | Fail | Fail | | 708 | uTorrent | | | | | | 709 | file seeding | | | | | | 710 +--------------+--------+--------+--------+--------------+----------+ 711 | Bit Torrent | Pass | Pass | Pass | Pass | | 712 | uTorrent | | | | | | 713 | file | | | | | | 714 | leeching | | | | | | 715 +--------------+--------+--------+--------+--------------+----------+ 716 +--------------+--------+--------+--------+--------------+----------+ 717 | Pandora | Pass | Pass | Pass | Pass | | 718 | internet | | | | | | 719 | radio | | | | | | 720 +--------------+--------+--------+--------+--------------+----------+ 721 | FTP server | Pass | Pass | Pass | Pass | | 722 +--------------+--------+--------+--------+--------------+----------+ 723 | Web | Pass | Pass | Pass | Pass | | 724 | conferencing | | | | | | 725 | GTM | | | | | | 726 +--------------+--------+--------+--------+--------------+----------+ 727 | Social | Pass | Pass | Pass | Pass | | 728 | Networking | | | | | | 729 | Facebook | | | | | | 730 +--------------+--------+--------+--------+--------------+----------+ 731 | Social | Pass | Pass | Pass | Pass | | 732 | Networking | | | | | | 733 | Webkinz | | | | | | 734 +--------------+--------+--------+--------+--------------+----------+ 735 | X-Lite for | Pass | Pass | Pass | Pass | | 736 | SIP calls | | | | | | 737 | with proxy | | | | | | 738 +--------------+--------+--------+--------+--------------+----------+ 739 | X-Lite for | Fail | Fail | Fail | Fail | | 740 | SIP calls no | | | | | | 741 | proxy | | | | | | 742 +--------------+--------+--------+--------+--------------+----------+ 743 | Skype text | Pass | Pass | Pass | Pass | | 744 | chat | | | | | | 745 +--------------+--------+--------+--------+--------------+----------+ 746 | Skype video | Pass | Pass | Pass | Pass | | 747 | chat | | | | | | 748 +--------------+--------+--------+--------+--------------+----------+ 749 | Oovoo | Pass | Pass | Pass | Pass | | 750 +--------------+--------+--------+--------+--------------+----------+ 751 | MS Smooth | Pass | Pass | Pass | Pass | | 752 | streaming | | | | | | 753 +--------------+--------+--------+--------+--------------+----------+ 754 | Internet | Pass | Pass | Pass | Pass | | 755 | Archive | | | | | | 756 | video | | | | | | 757 | streaming | | | | | | 758 +--------------+--------+--------+--------+--------------+----------+ 759 | Internet | Pass | Pass | Pass | Pass | | 760 | Archive | | | | | | 761 | audio | | | | | | 762 | streaming | | | | | | 763 +--------------+--------+--------+--------+--------------+----------+ 764 +--------------+--------+--------+--------+--------------+----------+ 765 | Internet | Pass | Pass | Pass | Pass | | 766 | Archive file | | | | | | 767 | download | | | | | | 768 +--------------+--------+--------+--------+--------------+----------+ 769 | Iclips | Pass | Pass | Pass | Pass | | 770 +--------------+--------+--------+--------+--------------+----------+ 772 NAT-444 774 4.2. DS-Lite 776 +---------------+--------+---------+-------------+------------------+ 777 | Test Scenario | DS-Lit | Duratio | Description | General | 778 | (per Test | eTest | nof Tes | of Test | Observations/Not | 779 | Plan) | Resul | tPerfor | Execution | es | 780 | | ts | med | | | 781 +---------------+--------+---------+-------------+------------------+ 782 | Video | Pass | 15 | | | 783 | streaming | | | | | 784 | over Netflix | | | | | 785 +---------------+--------+---------+-------------+------------------+ 786 | Video | Pass | 10 | | | 787 | streaming | | | | | 788 | over YouTube | | | | | 789 +---------------+--------+---------+-------------+------------------+ 790 | Video | Pass | 10 | | | 791 | streaming | | | | | 792 | over Joost | | | | | 793 +---------------+--------+---------+-------------+------------------+ 794 | On line | Pass | 15 | | | 795 | gaming (one | | | | | 796 | user) | | | | | 797 +---------------+--------+---------+-------------+------------------+ 798 | Peer to Peer | Fail | NA | user inside | Users inside | 799 | gaming (two | | | HN1 playing | both HN are not | 800 | users) | | | game | able to connect. | 801 | | | | against | The error shown | 802 | | | | user inside | on console- "The | 803 | | | | HN2 | game session is | 804 | | | | | no longer | 805 | | | | | available" | 806 +---------------+--------+---------+-------------+------------------+ 807 +---------------+--------+---------+-------------+------------------+ 808 | Bit | Fail | 12 | user on the | | 809 | Torrent/uTorr | | | internet is | | 810 | ent file | | | able to | | 811 | seeding | | | download | | 812 | | | | file using | | 813 | | | | proxy | | 814 | | | | server and | | 815 | | | | not | | 816 | | | | peer-to-pee | | 817 | | | | r | | 818 +---------------+--------+---------+-------------+------------------+ 819 | Bit | Pass | 10 | | | 820 | Torrent/uTorr | | | | | 821 | ent file | | | | | 822 | leeching | | | | | 823 +---------------+--------+---------+-------------+------------------+ 824 | Pandora | Pass | 10 | | | 825 | internet | | | | | 826 | radio | | | | | 827 +---------------+--------+---------+-------------+------------------+ 828 | FTP server | Pass | 700 Mb | | | 829 +---------------+--------+---------+-------------+------------------+ 830 | Web | Pass | 10 | | | 831 | conferencing | | | | | 832 | (GTM) | | | | | 833 +---------------+--------+---------+-------------+------------------+ 834 | Social | Pass | NA | | | 835 | Networking - | | | | | 836 | Facebook | | | | | 837 +---------------+--------+---------+-------------+------------------+ 838 | Social | Pass | NA | | | 839 | Networking - | | | | | 840 | Webkinz | | | | | 841 +---------------+--------+---------+-------------+------------------+ 842 | X-Lite (for | Pass | 10 | | | 843 | SIP calls) | | | | | 844 | (proxy given) | | | | | 845 +---------------+--------+---------+-------------+------------------+ 846 | X-Lite (for | Fail | NA | | | 847 | SIP calls) | | | | | 848 | (proxy not | | | | | 849 | given) | | | | | 850 +---------------+--------+---------+-------------+------------------+ 851 | Skype text | Pass | NA | | | 852 | chat | | | | | 853 +---------------+--------+---------+-------------+------------------+ 854 +---------------+--------+---------+-------------+------------------+ 855 | Skype video | Pass | 20 | | | 856 | chat | | | | | 857 +---------------+--------+---------+-------------+------------------+ 858 | Oovoo | Pass | 15 | | | 859 +---------------+--------+---------+-------------+------------------+ 860 | MS Smooth | Pass | 10 | | | 861 | streaming | | | | | 862 +---------------+--------+---------+-------------+------------------+ 863 | Internet | Pass | 10 | | | 864 | Archive - | | | | | 865 | video | | | | | 866 | streaming | | | | | 867 +---------------+--------+---------+-------------+------------------+ 868 | Internet | Pass | 5 | | | 869 | Archive - | | | | | 870 | audio | | | | | 871 | streaming | | | | | 872 +---------------+--------+---------+-------------+------------------+ 873 | Internet | Pass | 80 Mb | | | 874 | Archive - | | | | | 875 | file download | | | | | 876 +---------------+--------+---------+-------------+------------------+ 877 | Iclips | Pass | 10 | | | 878 +---------------+--------+---------+-------------+------------------+ 880 DSLite 882 5. 2010 Summary of Results 884 The tables below summarize results from 2010 NAT444 testing at 885 CableLabs, Time Warner Cable, and Rogers Communications. They are 886 included for comparison with 2011 results, documented above. 888 5.1. Case1: Single Client, Single Home Network, Single Service Provider 890 +--------------+---------------+------------------------------------+ 891 | Test Case | Results | Notes | 892 +--------------+---------------+------------------------------------+ 893 | Web browsing | pass | | 894 +--------------+---------------+------------------------------------+ 895 | Email | pass | | 896 +--------------+---------------+------------------------------------+ 897 | FTP download | pass | performance degraded on very large | 898 | | | downloads | 899 +--------------+---------------+------------------------------------+ 900 | Bittorrent | pass | | 901 | leeching | | | 902 +--------------+---------------+------------------------------------+ 903 | Bittorrent | fail | | 904 | seeding | | | 905 +--------------+---------------+------------------------------------+ 906 | Video | pass | | 907 | streaming | | | 908 +--------------+---------------+------------------------------------+ 909 | Voice chat | pass | | 910 +--------------+---------------+------------------------------------+ 911 | Netflix | pass | | 912 | streaming | | | 913 +--------------+---------------+------------------------------------+ 914 | Instant | pass | | 915 | Messaging | | | 916 +--------------+---------------+------------------------------------+ 917 | Ping | pass | | 918 +--------------+---------------+------------------------------------+ 919 | Traceroute | pass | | 920 +--------------+---------------+------------------------------------+ 921 | Remote | pass | | 922 | desktop | | | 923 +--------------+---------------+------------------------------------+ 924 | VPN | pass | | 925 +--------------+---------------+------------------------------------+ 926 | Xbox live | pass | | 927 +--------------+---------------+------------------------------------+ 928 | Xbox online | pass | Blocked by some LSNs. | 929 +--------------+---------------+------------------------------------+ 930 | Xbox network | fail | Your NAT type is moderate. For | 931 | test | | best online experience you need an | 932 | | | open NAT configuration. You | 933 | | | should enable UPnP on the router. | 934 +--------------+---------------+------------------------------------+ 935 +--------------+---------------+------------------------------------+ 936 | Nintendo Wii | pass behind | | 937 | | one LSN, fail | | 938 | | behind | | 939 | | another | | 940 +--------------+---------------+------------------------------------+ 941 | Playstation | pass | | 942 | 3 | | | 943 +--------------+---------------+------------------------------------+ 944 | Team | fail | pass behind one LSN, but | 945 | Fortress 2 | | performance degraded | 946 +--------------+---------------+------------------------------------+ 947 | Starcraft II | pass | | 948 +--------------+---------------+------------------------------------+ 949 | World of | pass | | 950 | Warcraft | | | 951 +--------------+---------------+------------------------------------+ 952 | Call of Duty | pass | performance degraded behind one | 953 | | | LSN | 954 +--------------+---------------+------------------------------------+ 955 | Slingcatcher | fail | | 956 +--------------+---------------+------------------------------------+ 957 | Netflix | fail | pass behind one LSN | 958 | Party (Xbox) | | | 959 +--------------+---------------+------------------------------------+ 960 | Hulu | pass | performance degraded behind one | 961 | | | LSN | 962 +--------------+---------------+------------------------------------+ 963 | AIM File | pass | performance degraded | 964 | Tranfer | | | 965 +--------------+---------------+------------------------------------+ 966 | Webcam | fail | | 967 +--------------+---------------+------------------------------------+ 968 | 6to4 | fail | | 969 +--------------+---------------+------------------------------------+ 970 | Teredo | fail | | 971 +--------------+---------------+------------------------------------+ 973 Case1 975 5.2. Case2: Two Clients, Single Home Network, Single Service Provider 977 +-----------------+---------+---------------------------------------+ 978 | Test Case | Results | Notes | 979 +-----------------+---------+---------------------------------------+ 980 | Bittorrent | pass | | 981 | leeching | | | 982 +-----------------+---------+---------------------------------------+ 983 | Bittorrent | fail | | 984 | seeding | | | 985 +-----------------+---------+---------------------------------------+ 986 | Video streaming | fail | | 987 +-----------------+---------+---------------------------------------+ 988 | Voice chat | pass | | 989 +-----------------+---------+---------------------------------------+ 990 | Netflix | pass | performance severely impacted, | 991 | streaming | | eventually failed | 992 +-----------------+---------+---------------------------------------+ 993 | IM | pass | | 994 +-----------------+---------+---------------------------------------+ 995 | Limewire | pass | | 996 | leeching | | | 997 +-----------------+---------+---------------------------------------+ 998 | Limewire | fail | | 999 | seeding | | | 1000 +-----------------+---------+---------------------------------------+ 1002 Case2 1004 5.3. Case3: Two Clients, Two Home Networks, Single Service Provider 1006 +-------------------+---------+-------+ 1007 | Test Case | Results | Notes | 1008 +-------------------+---------+-------+ 1009 | Limewire leeching | pass | | 1010 +-------------------+---------+-------+ 1011 | Limewire seeding | fail | | 1012 +-------------------+---------+-------+ 1013 | Utorrent leeching | pass | | 1014 +-------------------+---------+-------+ 1015 | Utorrent seeding | fail | | 1016 +-------------------+---------+-------+ 1018 Case3 1020 5.4. Case4: Two Clients, Two Home Networks, Two Service Providers Cross 1021 ISP 1023 +------------------+---------+-------+ 1024 | Test Case | Results | Notes | 1025 +------------------+---------+-------+ 1026 | Skype voice call | pass | | 1027 +------------------+---------+-------+ 1028 | IM | pass | | 1029 +------------------+---------+-------+ 1030 | FTP | fail | | 1031 +------------------+---------+-------+ 1032 | Facebook chat | pass | | 1033 +------------------+---------+-------+ 1034 | Skype video | pass | | 1035 +------------------+---------+-------+ 1037 Case4 1039 6. IANA Considerations 1041 This document has no IANA considerations. 1043 7. Security Considerations 1045 Security considerations are described in [I-D.shirasaki-nat444]. 1047 8. Informative References 1049 [I-D.shirasaki-nat444] 1050 Yamagata, I., Shirasaki, Y., Nakagawa, A., Yamaguchi, J., 1051 and H. Ashida, "NAT444", draft-shirasaki-nat444-02 (work 1052 in progress), July 2010. 1054 [RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and 1055 E. Lear, "Address Allocation for Private Internets", 1056 BCP 5, RFC 1918, February 1996. 1058 [RFC3056] Carpenter, B. and K. Moore, "Connection of IPv6 Domains 1059 via IPv4 Clouds", RFC 3056, February 2001. 1061 [RFC4380] Huitema, C., "Teredo: Tunneling IPv6 over UDP through 1062 Network Address Translations (NATs)", RFC 4380, 1063 February 2006. 1065 [RFC6269] Ford, M., Boucadair, M., Durand, A., Levis, P., and P. 1066 Roberts, "Issues with IP Address Sharing", RFC 6269, 1067 June 2011. 1069 [RFC6333] Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual- 1070 Stack Lite Broadband Deployments Following IPv4 1071 Exhaustion", RFC 6333, August 2011. 1073 Appendix A. Acknowledgements 1075 Thanks to the following people for their testing, guidance, and 1076 feedback: 1078 Paul Eldridge 1080 Abishek Chandrasekaran 1082 Vivek Ganti 1084 Joey Padden 1086 Lane Johnson 1088 Authors' Addresses 1090 Chris Donley (editor) 1091 CableLabs 1092 858 Coal Creek Circle 1093 Louisville, CO 80027 1094 USA 1096 Email: c.donley@cablelabs.com 1098 Lee Howard 1099 Time Warner Cable 1100 13241 Woodland Park Rd 1101 Herndon, VA 20171 1102 USA 1104 Email: william.howard@twcable.com 1105 Victor Kuarsingh 1106 Rogers Communications 1107 8200 Dixie Road 1108 Brampton, ON L6T 0C1 1109 Canada 1111 Email: victor.kuarsingh@rci.rogers.com 1113 John Berg 1114 CableLabs 1115 858 Coal Creek Circle 1116 Louisville, CO 80027 1117 USA 1119 Email: j.berg@cablelabs.com 1121 Jinesh Doshi 1122 University of Colorado 1124 Email: jinesh.doshi@colorado.edu