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Checking references for intended status: Informational ---------------------------------------------------------------------------- ** Obsolete normative reference: RFC 2870 (Obsoleted by RFC 7720) -- Obsolete informational reference (is this intentional?): RFC 5735 (Obsoleted by RFC 6890) Summary: 1 error (**), 0 flaws (~~), 3 warnings (==), 4 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group J. Abley 3 Internet-Draft ICANN 4 Intended status: Informational W. Maton 5 Expires: November 12, 2011 NRC-CNRC 6 May 11, 2011 8 AS112 Nameserver Operations 9 draft-ietf-dnsop-as112-ops-09 11 Abstract 13 Many sites connected to the Internet make use of IPv4 addresses that 14 are not globally-unique. Examples are the addresses designated in 15 RFC 1918 for private use within individual sites. 17 Devices in such environments may occasionally originate Domain Name 18 System (DNS) queries (so-called "reverse lookups") corresponding to 19 those private-use addresses. Since the addresses concerned have only 20 local significance, it is good practice for site administrators to 21 ensure that such queries are answered locally. However, it is not 22 uncommon for such queries to follow the normal delegation path in the 23 public DNS instead of being answered within the site. 25 It is not possible for public DNS servers to give useful answers to 26 such queries. In addition, due to the wide deployment of private-use 27 addresses and the continuing growth of the Internet, the volume of 28 such queries is large and growing. The AS112 project aims to provide 29 a distributed sink for such queries in order to reduce the load on 30 the IN-ADDR.ARPA authoritative servers. The AS112 project is named 31 after the Autonomous System Number (ASN) that was assigned to it. 33 This document describes the steps required to install a new AS112 34 node, and offers advice relating to such a node's operation. 36 Status of this Memo 38 This Internet-Draft is submitted in full conformance with the 39 provisions of BCP 78 and BCP 79. 41 Internet-Drafts are working documents of the Internet Engineering 42 Task Force (IETF). Note that other groups may also distribute 43 working documents as Internet-Drafts. The list of current Internet- 44 Drafts is at http://datatracker.ietf.org/drafts/current/. 46 Internet-Drafts are draft documents valid for a maximum of six months 47 and may be updated, replaced, or obsoleted by other documents at any 48 time. It is inappropriate to use Internet-Drafts as reference 49 material or to cite them other than as "work in progress." 51 This Internet-Draft will expire on November 12, 2011. 53 Copyright Notice 55 Copyright (c) 2011 IETF Trust and the persons identified as the 56 document authors. All rights reserved. 58 This document is subject to BCP 78 and the IETF Trust's Legal 59 Provisions Relating to IETF Documents 60 (http://trustee.ietf.org/license-info) in effect on the date of 61 publication of this document. Please review these documents 62 carefully, as they describe your rights and restrictions with respect 63 to this document. Code Components extracted from this document must 64 include Simplified BSD License text as described in Section 4.e of 65 the Trust Legal Provisions and are provided without warranty as 66 described in the Simplified BSD License. 68 This document may contain material from IETF Documents or IETF 69 Contributions published or made publicly available before November 70 10, 2008. The person(s) controlling the copyright in some of this 71 material may not have granted the IETF Trust the right to allow 72 modifications of such material outside the IETF Standards Process. 73 Without obtaining an adequate license from the person(s) controlling 74 the copyright in such materials, this document may not be modified 75 outside the IETF Standards Process, and derivative works of it may 76 not be created outside the IETF Standards Process, except to format 77 it for publication as an RFC or to translate it into languages other 78 than English. 80 Table of Contents 82 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 83 2. AS112 DNS Service . . . . . . . . . . . . . . . . . . . . . . 5 84 2.1. Zones . . . . . . . . . . . . . . . . . . . . . . . . . . 5 85 2.2. Nameservers . . . . . . . . . . . . . . . . . . . . . . . 5 86 3. Installation of a New Node . . . . . . . . . . . . . . . . . . 6 87 3.1. Useful Background Knowledge . . . . . . . . . . . . . . . 6 88 3.2. Topological Location . . . . . . . . . . . . . . . . . . . 6 89 3.3. Operating System and Host Considerations . . . . . . . . . 6 90 3.4. Routing Software . . . . . . . . . . . . . . . . . . . . . 7 91 3.5. DNS Software . . . . . . . . . . . . . . . . . . . . . . . 8 92 3.6. Testing a Newly-Installed Node . . . . . . . . . . . . . . 12 93 4. Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 13 94 4.1. Monitoring . . . . . . . . . . . . . . . . . . . . . . . . 13 95 4.2. Downtime . . . . . . . . . . . . . . . . . . . . . . . . . 13 96 4.3. Statistics and Measurement . . . . . . . . . . . . . . . . 13 97 5. Communications . . . . . . . . . . . . . . . . . . . . . . . . 14 98 6. On the Future of AS112 Nodes . . . . . . . . . . . . . . . . . 15 99 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 100 8. Security Considerations . . . . . . . . . . . . . . . . . . . 17 101 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 18 102 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19 103 10.1. Normative References . . . . . . . . . . . . . . . . . . . 19 104 10.2. Informative References . . . . . . . . . . . . . . . . . . 19 105 Appendix A. History . . . . . . . . . . . . . . . . . . . . . . . 21 106 Appendix B. Change History . . . . . . . . . . . . . . . . . . . 22 107 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 23 109 1. Introduction 111 Many sites connected to the Internet make use of IPv4 addresses that 112 are not globally unique. Examples are the addresses designated in 113 [RFC1918] for private use within individual sites. 115 Devices in such environments may occasionally originate Domain Name 116 System (DNS) [RFC1034] queries (so-called "reverse lookups") 117 corresponding to those private-use addresses. Since the addresses 118 concerned have only local significance, it is good practice for site 119 administrators to ensure that such queries are answered locally 120 [I-D.ietf-dnsop-default-local-zones]. However, it is not uncommon 121 for such queries to follow the normal delegation path in the public 122 DNS instead of being answered within the site. 124 It is not possible for public DNS servers to give useful answers to 125 such queries. In addition, due to the wide deployment of private-use 126 addresses and the continuing growth of the Internet, the volume of 127 such queries is large and growing. The AS112 project aims to provide 128 a distributed sink for such queries in order to reduce the load on 129 the IN-ADDR.ARPA authoritative servers [RFC5855]. 131 The AS112 project encompasses a loosely coordinated collection of 132 independently operated nameservers. Each nameserver functions as a 133 single node in an AS112 anycast cloud [RFC4786], and is configured to 134 answer authoritatively for a particular set of nominated zones. 136 The AS112 project is named after the Autonomous System Number (ASN) 137 that was assigned to it. 139 2. AS112 DNS Service 141 2.1. Zones 143 AS112 nameservers answer authoritatively for the following zones, 144 corresponding to [RFC1918] private-use netblocks: 146 o 10.IN-ADDR.ARPA 148 o 16.172.IN-ADDR.ARPA, 17.172.IN-ADDR.ARPA, ..., 31.172.IN-ADDR.ARPA 150 o 168.192.IN-ADDR.ARPA 152 and the following zone, corresponding to the "link local" netblock 153 169.254.0.0/16 listed in [RFC5735]: 155 o 254.169.IN-ADDR.ARPA 157 To aid identification of AS112 anycast nodes, each node also answers 158 authoritatively for the zone HOSTNAME.AS112.NET. 160 See Section 3.5 for the recommended contents of all these zones. 162 It is possible that other zones corresponding to private-use 163 infrastructure will be delegated to AS112 servers in the future. A 164 list of zones for which AS112 servers answer authoritatively is 165 maintained at . 167 2.2. Nameservers 169 The zones listed in Section 2.1 are delegated to the two nameservers 170 BLACKHOLE-1.IANA.ORG (192.175.48.6) and BLACKHOLE-2.IANA.ORG 171 (192.175.48.42). 173 Additionally, the server PRISONER.IANA.ORG (192.175.48.1) is listed 174 in the MNAME field of the SOA records of the IN-ADDR.ARPA zones 175 served by AS112 nameservers. PRISONER.IANA.ORG receives mainly 176 dynamic update queries. 178 The addresses of all these nameservers are covered by the single IPv4 179 prefix 192.175.48.0/24. 181 3. Installation of a New Node 183 3.1. Useful Background Knowledge 185 Installation of an AS112 node is relatively straightforward. 186 However, experience in the following general areas may prove useful: 188 o inter-domain routing with BGP [RFC4271]; 190 o DNS authoritative server operations; 192 o anycast [RFC4786] distribution of DNS services. 194 3.2. Topological Location 196 AS112 nodes may be located anywhere on the Internet. For nodes that 197 are intended to provide a public service to the Internet community 198 (as opposed to private use), it may well be advantageous to choose a 199 location that is easily (and cheaply) reachable by multiple 200 providers, such as an Internet exchange point. 202 AS112 nodes may advertise their service prefix to BGP peers for local 203 use (analogous to a conventional peering relationship between two 204 providers) or for global use (analogous to a customer relationship 205 with one or more providers). 207 It is good operational practice to notify the community of users that 208 may fall within the reach of a new AS112 node before it is installed. 209 At an Internet Exchange, local mailing lists usually exist to 210 facilitate such announcements. For nodes that are intended to be 211 globally reachable, coordination with other AS112 operators is highly 212 recommended. See also Section 5. 214 3.3. Operating System and Host Considerations 216 Examples in this document are based on UNIX and UNIX-like operating 217 systems, but other operating systems exist which are suitable for use 218 in construction of an AS112 node. 220 The chosen platform should include support for either cloned loopback 221 interfaces, or the capability to bind multiple addresses to a single 222 loopback interface. The addresses of the nameservers listed in 223 Section 2.2 will be configured on these interfaces in order that the 224 DNS software can respond to queries properly. 226 A host that is configured to act as an AS112 anycast node should be 227 dedicated to that purpose, and should not be used to simultaneously 228 provide other services. This guidance is provided due to the 229 unpredictable (and occasionally high) traffic levels that AS112 nodes 230 have been seen to attract. 232 System startup scripts should be arranged such that the various 233 AS112-related components start automatically following a system 234 reboot. The order in which interfaces are configured and software 235 components started should be arranged such that routing software 236 startup follows DNS software startup, and DNS software startup 237 follows loopback interface configuration. 239 Wrapper scripts or other arrangements should be employed to ensure 240 that the anycast service prefix for AS112 is not advertised while 241 either the anycast addresses are not configured, or while the DNS 242 software is not running. 244 3.4. Routing Software 246 AS112 nodes signal the availability of AS112 nameservers to the 247 Internet using BGP [RFC4271]: each AS112 node is a BGP speaker, and 248 announces the prefix 192.175.48.0/24 to the Internet with origin AS 249 112 (see also Section 2.2). 251 The examples in this document are based on the Quagga Routing 252 Suite [1] running on Linux, but other software packages exist which 253 also provide suitable BGP support for AS112 nodes. 255 The "bgpd.conf" file is used by Quagga's bgpd daemon, which provides 256 BGP protocol support. The router id in this example is 203.0.113.1; 257 the AS112 node peers with external peers 192.0.2.1 and 192.0.2.2. 258 Note the local AS number 112, and the origination of the prefix 259 192.175.48.0/24. 261 ! bgpd.conf 262 ! 263 hostname as112-bgpd 264 password 265 enable password 266 ! 267 ! Note that all AS112 nodes use the local Autonomous System 268 ! Number 112, and originate the IPv4 prefix 192.175.48.0/24. 269 ! All other addresses shown below are illustrative, and 270 ! actual numbers will depend on local circumstances. 271 ! 272 router bgp 112 273 bgp router-id 203.0.113.1 274 network 192.175.48.0 275 neighbor 192.0.2.1 remote-as 64496 276 neighbor 192.0.2.1 next-hop-self 277 neighbor 192.0.2.2 remote-as 64497 278 neighbor 192.0.2.2 next-hop-self 280 The "zebra.conf" file is required to provide integration between 281 protocol daemons (bgpd, in this case) and the kernel. 283 ! zebra.conf 284 ! 285 hostname as112 286 password 287 enable password 288 ! 289 interface lo 290 ! 291 interface eth0 292 ! 294 3.5. DNS Software 296 Although the queries received by AS112 nodes are definitively 297 misdirected, it is important that they be answered in a manner that 298 is accurate and consistent. For this reason AS112 nodes operate as 299 fully-functional and standards-compliant DNS authoritative servers 300 [RFC1034], and hence require DNS software. 302 Examples in this document are based on ISC BIND9 [2], but other DNS 303 software exists which is suitable for use in construction of an AS112 304 node. 306 The following is a sample BIND9 "named.conf" file for a dedicated 307 AS112 server. Note that the nameserver is configured to act as an 308 authoritative-only server (i.e. recursion is disabled). The 309 nameserver is also configured to listen on the various AS112 anycast 310 nameserver addresses, as well as its local addresses. 312 // named.conf 314 // global options 316 options { 317 listen-on { 318 127.0.0.1; // localhost 320 // the following address is node-dependent, and should be set to 321 // something appropriate for the new AS112 node 323 203.0.113.1; // local address (globally-unique, unicast) 325 // the following addresses correspond to AS112 addresses, and 326 // are the same for all AS112 nodes 328 192.175.48.1; // prisoner.iana.org (anycast) 329 192.175.48.6; // blackhole-1.iana.org (anycast) 330 192.175.48.42; // blackhole-2.iana.org (anycast) 331 }; 332 directory "/var/named"; 333 recursion no; // authoritative-only server 334 query-source address *; 335 }; 337 // log queries, so that when people call us about unexpected 338 // answers to queries they didn't realise they had sent, we 339 // have something to talk about. Note that activating this 340 // has the potential to create high CPU load and consume 341 // enormous amounts of disk space. 343 logging { 344 channel "querylog" { 345 file "/var/log/query.log" versions 2 size 500m; 346 print-time yes; 347 }; 348 category queries { querylog; }; 349 }; 351 // RFC 1918 353 zone "10.in-addr.arpa" { type master; file "db.empty"; }; 354 zone "16.172.in-addr.arpa" { type master; file "db.empty"; }; 355 zone "17.172.in-addr.arpa" { type master; file "db.empty"; }; 356 zone "18.172.in-addr.arpa" { type master; file "db.empty"; }; 357 zone "19.172.in-addr.arpa" { type master; file "db.empty"; }; 358 zone "20.172.in-addr.arpa" { type master; file "db.empty"; }; 359 zone "21.172.in-addr.arpa" { type master; file "db.empty"; }; 360 zone "22.172.in-addr.arpa" { type master; file "db.empty"; }; 361 zone "23.172.in-addr.arpa" { type master; file "db.empty"; }; 362 zone "24.172.in-addr.arpa" { type master; file "db.empty"; }; 363 zone "25.172.in-addr.arpa" { type master; file "db.empty"; }; 364 zone "26.172.in-addr.arpa" { type master; file "db.empty"; }; 365 zone "27.172.in-addr.arpa" { type master; file "db.empty"; }; 366 zone "28.172.in-addr.arpa" { type master; file "db.empty"; }; 367 zone "29.172.in-addr.arpa" { type master; file "db.empty"; }; 368 zone "30.172.in-addr.arpa" { type master; file "db.empty"; }; 369 zone "31.172.in-addr.arpa" { type master; file "db.empty"; }; 370 zone "168.192.in-addr.arpa" { type master; file "db.empty"; }; 372 // RFC 5735 374 zone "254.169.in-addr.arpa" { type master; file "db.empty"; }; 376 // also answer authoritatively for the HOSTNAME.AS112.NET zone, 377 // which contains data of operational relevance 379 zone "hostname.as112.net" { 380 type master; 381 file "db.hostname.as112.net"; 382 }; 384 The "db.empty" file follows, below. This is the source data used to 385 populate all the IN-ADDR.ARPA zones listed in Section 2.1. Note that 386 the RNAME specified in the SOA record corresponds to 387 hostmaster@root-servers.org, a suitable e-mail address for receiving 388 technical queries about these zones. 390 ; db.empty 391 ; 392 ; Empty zone for AS112 server. 393 ; 394 $TTL 1W 395 @ IN SOA prisoner.iana.org. hostmaster.root-servers.org. ( 396 1 ; serial number 397 1W ; refresh 398 1M ; retry 399 1W ; expire 400 1W ) ; negative caching TTL 401 ; 402 NS blackhole-1.iana.org. 403 NS blackhole-2.iana.org. 404 ; 405 ; There should be no other resource records included in this zone. 406 ; 407 ; Records that relate to RFC 1918-numbered resources within the 408 ; site hosting this AS112 node should not be hosted on this 409 ; nameserver. 411 The "db.hostname.as112.net" file follows, below. This zone contains 412 various resource records that provide operational data to users for 413 troubleshooting or measurement purposes, and should be edited to suit 414 local circumstances. Note that the response to the query 415 "HOSTNAME.AS112.NET IN TXT" should fit within a 512 octet DNS/UDP 416 datagram: i.e. it should be available over UDP transport without 417 requiring EDNS0 support. 419 The optional LOC record [RFC1876] included in the zone apex provides 420 information about the geospatial location of the node. 422 ; db.hostname.as112.net 423 ; 424 $TTL 1W 425 @ SOA server.example.net. admin.example.net. ( 426 1 ; serial number 427 1W ; refresh 428 1M ; retry 429 1W ; expire 430 1W ) ; negative caching TTL 431 ; 432 NS blackhole-2.iana.org. 433 NS blackhole-1.iana.org. 434 ; 435 TXT "Name of Facility or similar" "City, Country" 436 TXT "See http://www.as112.net/ for more information." 437 ; 438 LOC 45 25 0.000 N 75 42 0.000 W 80.00m 1m 10000m 10m 440 3.6. Testing a Newly-Installed Node 442 The BIND9 tool "dig" can be used to retrieve the TXT resource records 443 associated with the domain "HOSTNAME.AS112.NET", directed at one of 444 the AS112 anycast nameserver addresses. Continuing the example from 445 above, the response received should indicate the identity of the 446 AS112 node that responded to the query. See Section 3.5 for more 447 details about the resource records associated with 448 "HOSTNAME.AS112.NET". 450 % dig @prisoner.iana.org hostname.as112.net txt +short +norec 451 "Name of Facility or similar" "City, Country" 452 "See http://www.as112.net/ for more information." 453 % 455 If the response received indicates a different node is being used, 456 then there is probably a routing problem to solve. If there is no 457 response received at all, there might be host or nameserver problem. 458 Judicious use of tools such as traceroute, and consultation of BGP 459 looking glasses might be useful in troubleshooting. 461 Note that an appropriate set of tests for a new server will include 462 queries sent from many different places within the expected service 463 area of the node, using both UDP and TCP transport, and exercising 464 all three AS112 anycast nameserver addresses. 466 4. Operations 468 4.1. Monitoring 470 AS112 nodes should be monitored to ensure they are functioning 471 correctly, just as with any other production service. An AS112 node 472 that stops answering queries correctly can cause failures and 473 timeouts in unexpected places and can lead to failures in dependent 474 systems that can be difficult to troubleshoot. 476 4.2. Downtime 478 An AS112 node that needs to go off-line (e.g. for planned maintenance 479 or as part of the diagnosis of some problem) should stop advertising 480 the AS112 service prefix to its BGP peers. This can be done by 481 shutting down the routing software on the node altogether or by 482 causing the routing system to withdraw the route. 484 Withdrawing the service prefix is important in order to avoid 485 blackholing query traffic in the event that the DNS software on the 486 node is not functioning normally. 488 4.3. Statistics and Measurement 490 Use of the AS112 node should be measured in order to track long-term 491 trends, identify anomalous conditions, and to ensure that the 492 configuration of the AS112 node is sufficient to handle the query 493 load. 495 Examples of free monitoring tools that might be useful to operators 496 of AS112 nodes include: 498 o bindgraph [3] 500 o dnstop [4] 502 o DSC [5] 504 5. Communications 506 It is good operational practice to notify the community of users that 507 may fall within the reach of a new AS112 node before it is installed. 508 At Internet Exchanges, local mailing lists usually exist to 509 facilitate such announcements. 511 For nodes that are intended to be globally reachable, coordination 512 with other AS112 operators is especially recommended. The mailing 513 list is operated for this 514 purpose. 516 Information pertinent to AS112 operations is maintained at 517 . 519 Information about an AS112 node should also be published within the 520 DNS, within the "HOSTNAME.AS112.NET" zone. See Section 3.5 for more 521 details. 523 6. On the Future of AS112 Nodes 525 It is recommended practice for the operators of recursive nameservers 526 to answer queries for zones served by AS112 nodes locally, such that 527 queries never have an opportunity to reach AS112 servers 528 [I-D.ietf-dnsop-default-local-zones]. Operational experience with 529 AS112 nodes does not currently indicate an observable trend towards 530 compliance with those recommendations, however. 532 It is expected that some DNS software vendors will include default 533 configuration that will implement measures such as those described in 534 [I-D.ietf-dnsop-default-local-zones]. If such software is widely 535 deployed, it is reasonable to assume that the query load received by 536 AS112 nodes will decrease; however, it is safe to assume that the 537 query load will not decrease to zero, and consequently that AS112 538 nodes will continue to provide a useful service for the foreseeable 539 future. 541 There may be a requirement in the future for AS112 nodes to answer 542 for their current set of zones over IPv6 transport. Such a 543 requirement would necessitate the assignment of a corresponding IPv6 544 netblock for use as an anycast service prefix. 546 There may be a requirement in the future for AS112 nodes to serve 547 additional zones, or to stop serving particular zones that are 548 currently served. Such changes would be widely announced in 549 operational forums, and published at . 551 7. IANA Considerations 553 The AS112 nameservers are all named under the domain IANA.ORG (see 554 Section 2.2). However, the anycast infrastructure itself is operated 555 by a loosely-coordinated, diverse mix of organisations across the 556 Internet, and is not an IANA function. 558 The autonomous system number 112 and the IPv4 prefix 192.175.48.0/24 559 were assigned by ARIN. 561 This document makes no request of the IANA. 563 8. Security Considerations 565 Hosts should never normally send queries to AS112 servers; queries 566 relating to private-use addresses should be answered locally within a 567 site. Hosts that send queries to AS112 servers may well leak 568 information relating to private infrastructure to the public network, 569 and this could present a security risk. This risk is orthogonal to 570 the presence or absence of authoritative servers for these zones in 571 the public DNS infrastructure, however. 573 Queries that are answered by AS112 servers are usually unintentional; 574 it follows that the responses from AS112 servers are usually 575 unexpected. Unexpected inbound traffic can trigger intrusion 576 detection systems or alerts by firewalls. Operators of AS112 servers 577 should be prepared to be contacted by operators of remote 578 infrastructure who believe their security has been violated. Advice 579 to those who mistakenly believe that responses from AS112 nodes 580 constitutes an attack on their infrastructure can be found in 581 [I-D.ietf-dnsop-as112-under-attack-help-help]. 583 The deployment of AS112 nodes is very loosely coordinated compared to 584 other services distributed using anycast. The malicious compromise 585 of an AS112 node and subversion of the data served by the node is 586 hence more difficult to detect due to the lack of central management. 587 Since it is conceivable that changing the responses to queries 588 received by AS112 nodes might influence the behaviour of the hosts 589 sending the queries, such a compromise might be used as an attack 590 vector against private infrastructure. 592 Operators of AS112 should take appropriate measures to ensure that 593 AS112 nodes are appropriately protected from compromise, such as 594 would normally be employed for production nameserver or network 595 infrastructure. The guidance provided for root nameservers in 596 [RFC2870] may be instructive. 598 The zones hosted by AS112 servers are not signed with DNSSEC 599 [RFC4033]. Given the distributed and loosely-coordinated structure 600 of the AS112 service, the zones concerned could only be signed if the 601 private key material used was effectively public, obviating any 602 security benefit resulting from the use of those keys. 604 9. Acknowledgements 606 The authors wish to acknowledge the assistance of Bill Manning, John 607 Brown, Marco D'Itri, Daniele Arena, Stephane Bortzmeyer, Frank 608 Habicht, Chris Thompson, Peter Losher, Peter Koch, Alfred Hoenes and 609 S. Moonesamy in the preparation of this document. 611 10. References 613 10.1. Normative References 615 [RFC1034] Mockapetris, P., "Domain names - concepts and facilities", 616 STD 13, RFC 1034, November 1987. 618 [RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and 619 E. Lear, "Address Allocation for Private Internets", 620 BCP 5, RFC 1918, February 1996. 622 [RFC2870] Bush, R., Karrenberg, D., Kosters, M., and R. Plzak, "Root 623 Name Server Operational Requirements", BCP 40, RFC 2870, 624 June 2000. 626 [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S. 627 Rose, "DNS Security Introduction and Requirements", 628 RFC 4033, March 2005. 630 [RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway 631 Protocol 4 (BGP-4)", RFC 4271, January 2006. 633 [RFC4786] Abley, J. and K. Lindqvist, "Operation of Anycast 634 Services", BCP 126, RFC 4786, December 2006. 636 10.2. Informative References 638 [I-D.ietf-dnsop-as112-under-attack-help-help] 639 Abley, J. and W. Maton, "I'm Being Attacked by 640 PRISONER.IANA.ORG!", 641 draft-ietf-dnsop-as112-under-attack-help-help-06 (work in 642 progress), April 2011. 644 [I-D.ietf-dnsop-default-local-zones] 645 Andrews, M., "Locally-served DNS Zones", 646 draft-ietf-dnsop-default-local-zones-15 (work in 647 progress), March 2011. 649 [RFC1876] Davis, C., Vixie, P., Goodwin, T., and I. Dickinson, "A 650 Means for Expressing Location Information in the Domain 651 Name System", RFC 1876, January 1996. 653 [RFC5735] Cotton, M. and L. Vegoda, "Special Use IPv4 Addresses", 654 BCP 153, RFC 5735, January 2010. 656 [RFC5855] Abley, J. and T. Manderson, "Nameservers for IPv4 and IPv6 657 Reverse Zones", BCP 155, RFC 5855, May 2010. 659 URIs 661 [1] 663 [2] 665 [3] 667 [4] 669 [5] 671 Appendix A. History 673 Widespread use of the private address blocks listed in [RFC1918] 674 followed that document's publication in 1996. At that time the IN- 675 ADDR.ARPA zone was served by root servers. 677 The idea of off-loading IN-ADDR.ARPA queries relating to [RFC1918] 678 addresses from the root nameservers was first proposed by Bill 679 Manning and John Brown. 681 The use of anycast for distributing authoritative DNS service for 682 [RFC1918] IN-ADDR.ARPA zones was subsequently proposed at a private 683 meeting of root server operators. 685 ARIN provided an IPv4 prefix for the anycast service, and also the 686 autonomous system number 112 for use in originating that prefix. 687 This assignment gave the project its name. 689 In 2002 the first AS112 anycast nodes were deployed. 691 In 2011 the IN-ADDR.ARPA zone was redelegated from the root servers 692 to a new set of servers operated independently by AfriNIC, APNIC, 693 ARIN, ICANN, LACNIC and the RIPE NCC and named according to 694 [RFC5855]. 696 The use of anycast nameservers in the AS112 project contributed to 697 the operational experience of anycast DNS services, and can be seen 698 as a precursor to the anycast distribution of other authoritative DNS 699 servers in subsequent years (e.g. various root servers). 701 Appendix B. Change History 703 This section to be removed prior to publication. 705 00 Initial draft, circulated as draft-jabley-as112-ops-00 and 706 reviewed at the DNSOP working group meeting at IETF 66. 708 00 Document adoped by the DNSOP working group and renamed 709 accordingly. 711 01 Input from reviewers of DNSOP and others, some cosmetic tweaks. 713 02 Version bump as request by DNSOP chairs. Added missing IANA 714 Considerations section. Updated author's addresses. Make 715 http://www.as112.net/ URL consistent. 717 03 Fix BLACKHOLE-2.IANA.ORG IP address. 719 04 Bump version number. Refresh references. Add reference to BIRD. 720 Minor wordsmithing. 722 05 Updated following review from Peter Koch. 724 06 Updated following review from Alfred Hoenes. 726 07 Updated following IESG review. 728 08 Updated following review by S. Moonesamy. 730 09 Updated following review by Peter Koch. 732 Authors' Addresses 734 Joe Abley 735 ICANN 736 4676 Admiralty Way, Suite 330 737 Marina del Rey, CA 90292 738 US 740 Phone: +1 519 670 9327 741 Email: joe.abley@icann.org 743 William F. Maton Sotomayor 744 National Research Council of Canada 745 1200 Montreal Road 746 Ottawa, ON K1A 0R6 747 Canada 749 Phone: +1 613 993 0880 750 Email: wmaton@ryouko.imsb.nrc.ca