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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-10) exists of draft-ietf-dnsop-serve-stale-08 ** Obsolete normative reference: RFC 2434 (Obsoleted by RFC 5226) ** Obsolete normative reference: RFC 2671 (Obsoleted by RFC 6891) -- Obsolete informational reference (is this intentional?): RFC 2845 (Obsoleted by RFC 8945) Summary: 2 errors (**), 0 flaws (~~), 2 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group W. Kumari 3 Internet-Draft Google 4 Intended status: Standards Track E. Hunt 5 Expires: April 3, 2020 ISC 6 R. Arends 7 ICANN 8 W. Hardaker 9 USC/ISI 10 D. Lawrence 11 Oracle + Dyn 12 October 01, 2019 14 Extended DNS Errors 15 draft-ietf-dnsop-extended-error-12 17 Abstract 19 This document defines an extensible method to return additional 20 information about the cause of DNS errors. Though created primarily 21 to extend SERVFAIL to provide additional information about the cause 22 of DNS and DNSSEC failures, the Extended DNS Errors option defined in 23 this document allows all response types to contain extended error 24 information. Extended DNS Error information does not change the 25 processing of RCODEs. 27 Status of This Memo 29 This Internet-Draft is submitted in full conformance with the 30 provisions of BCP 78 and BCP 79. 32 Internet-Drafts are working documents of the Internet Engineering 33 Task Force (IETF). Note that other groups may also distribute 34 working documents as Internet-Drafts. The list of current Internet- 35 Drafts is at http://datatracker.ietf.org/drafts/current/. 37 Internet-Drafts are draft documents valid for a maximum of six months 38 and may be updated, replaced, or obsoleted by other documents at any 39 time. It is inappropriate to use Internet-Drafts as reference 40 material or to cite them other than as "work in progress." 42 This Internet-Draft will expire on April 3, 2020. 44 Copyright Notice 46 Copyright (c) 2019 IETF Trust and the persons identified as the 47 document authors. All rights reserved. 49 This document is subject to BCP 78 and the IETF Trust's Legal 50 Provisions Relating to IETF Documents 51 (http://trustee.ietf.org/license-info) in effect on the date of 52 publication of this document. Please review these documents 53 carefully, as they describe your rights and restrictions with respect 54 to this document. Code Components extracted from this document must 55 include Simplified BSD License text as described in Section 4.e of 56 the Trust Legal Provisions and are provided without warranty as 57 described in the Simplified BSD License. 59 Table of Contents 61 1. Introduction and background . . . . . . . . . . . . . . . . . 3 62 1.1. Requirements notation . . . . . . . . . . . . . . . . . . 4 63 2. Extended DNS Error EDNS0 option format . . . . . . . . . . . 4 64 3. Defined Extended DNS Errors . . . . . . . . . . . . . . . . . 5 65 3.1. Extended DNS Error Code 0 - Other . . . . . . . . . . . . 5 66 3.2. Extended DNS Error Code 1 - 67 Unsupported DNSKEY Algorithm . . . . . . . . . . . . . . 5 68 3.3. Extended DNS Error Code 2 - Unsupported DS 69 Digest Type . . . . . . . . . . . . . . . . . . . . . . . 5 70 3.4. Extended DNS Error Code 3 - Stale Answer . . . . . . . . 5 71 3.5. Extended DNS Error Code 4 - Forged Answer . . . . . . . . 6 72 3.6. Extended DNS Error Code 5 - DNSSEC Indeterminate . . . . 6 73 3.7. Extended DNS Error Code 6 - DNSSEC Bogus . . . . . . . . 6 74 3.8. Extended DNS Error Code 7 - Signature Expired . . . . . . 6 75 3.9. Extended DNS Error Code 8 - Signature Not Yet Valid . . . 6 76 3.10. Extended DNS Error Code 9 - DNSKEY Missing . . . . . . . 6 77 3.11. Extended DNS Error Code 10 - RRSIGs Missing . . . . . . . 6 78 3.12. Extended DNS Error Code 11 - No Zone Key Bit Set . . . . 6 79 3.13. Extended DNS Error Code 12 - NSEC Missing . . . . . . . . 6 80 3.14. Extended DNS Error Code 13 - Cached Error . . . . . . . . 7 81 3.15. Extended DNS Error Code 14 - Not Ready . . . . . . . . . 7 82 3.16. Extended DNS Error Code 15 - Blocked . . . . . . . . . . 7 83 3.17. Extended DNS Error Code 16 - Censored . . . . . . . . . . 7 84 3.18. Extended DNS Error Code 17 - Filtered . . . . . . . . . . 7 85 3.19. Extended DNS Error Code 18 - Prohibited . . . . . . . . . 7 86 3.20. Extended DNS Error Code 19 - Stale NXDOMAIN Answer . . . 7 87 3.21. Extended DNS Error Code 20 - Not Authoritative . . . . . 8 88 3.22. Extended DNS Error Code 21 - Not Supported . . . . . . . 8 89 3.23. Extended DNS Error Code 22 - No Reachable Authority . . . 8 90 3.24. Extended DNS Error Code 23 - Network Error . . . . . . . 8 91 3.25. Extended DNS Error Code 24 - Invalid Data . . . . . . . . 8 92 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 93 4.1. A New Extended DNS Error Code EDNS Option . . . . . . . . 8 94 4.2. New Registry Table for Extended DNS Error Codes . . . . . 8 95 5. Security Considerations . . . . . . . . . . . . . . . . . . . 11 96 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11 97 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 98 7.1. Normative References . . . . . . . . . . . . . . . . . . 12 99 7.2. Informative References . . . . . . . . . . . . . . . . . 12 100 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 102 1. Introduction and background 104 There are many reasons that a DNS query may fail, some of them 105 transient, some permanent; some can be resolved by querying another 106 server, some are likely best handled by stopping resolution. 107 Unfortunately, the error signals that a DNS server can return are 108 very limited, and are not very expressive. This means that 109 applications and resolvers often have to "guess" at what the issue is 110 - e.g. was the answer marked REFUSED because of a lame delegation, or 111 because the nameserver is still starting up and loading zones? Is a 112 SERVFAIL a DNSSEC validation issue, or is the nameserver experiencing 113 some other failure? What error messages should be presented to the 114 user or logged under these conditions? 116 A good example of issues that would benefit by additional error 117 information are errors caused by DNSSEC validation issues. When a 118 stub resolver queries a name which is DNSSEC bogus (using a 119 validating resolver), the stub resolver receives only a SERVFAIL in 120 response. Unfortunately, the SERVFAIL Response Code (RCODE) is used 121 to signal many sorts of DNS errors, and so the stub resolvers only 122 option is to ask the next configured DNS resolver. The result of 123 trying the next resolver is one of two outcomes: either the next 124 resolver also validates, and a SERVFAIL is returned again or the next 125 resolver is not a validating resolver, and the user is returned a 126 potentially harmful result. With an Extended DNS Error (EDE) option 127 enclosed in the response message, the resolver is able to return a 128 more descriptive reason as to why any failures happened, or add 129 additional context to a message containing a NOERROR RCODE. 131 This document specifies a mechanism to extend DNS errors to provide 132 additional information about the cause of an error. These extended 133 DNS error codes described in this document and can be used by any 134 system that sends DNS queries and receives a response containing an 135 EDE option. Different codes are useful in different circumstances, 136 and thus different systems (stub resolvers, recursive resolvers, and 137 authoritative resolvers) might receive and use them. 139 This document does not allow or prohibit any particular extended 140 error codes and information to be matched with any particular RCODEs. 141 Some combinations of extended error codes and RCODEs may seem 142 nonsensical (such as resolver-specific extended error codes in 143 responses from authoritative servers), so systems interpreting the 144 extended error codes MUST NOT assume that a combination will make 145 sense. Receivers MUST be able to accept EDE codes and EXTRA-TEXT in 146 all messages, including those with a NOERROR RCODE. Applications 147 MUST continue to follow requirements from applicable specs on how to 148 process RCODEs no matter what EDE values is also received. Senders 149 MAY include more than one EDE option and receivers MUST be able to 150 accept (but not necessarily process or act on) multiple EDE options 151 in a DNS message. 153 1.1. Requirements notation 155 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 156 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 157 document are to be interpreted as described in [RFC2119]. 159 2. Extended DNS Error EDNS0 option format 161 This draft uses an EDNS0 ([RFC2671]) option to include Extended DNS 162 Error (EDE) information in DNS messages. The option is structured as 163 follows: 165 1 1 1 1 1 1 166 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 167 +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ 168 0: | OPTION-CODE | 169 +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ 170 2: | OPTION-LENGTH | 171 +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ 172 4: | INFO-CODE | 173 +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ 174 6: / EXTRA-TEXT ... / 175 +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ 177 Field definition details: 179 o OPTION-CODE, 2-octets/16-bits (defined in [RFC6891]]), for EDE is 180 TBD. [RFC Editor: change TBD to the proper code once assigned by 181 IANA.] 182 o OPTION-LENGTH, 2-octets/16-bits ((defined in [RFC6891]]) contains 183 the length of the payload (everything after OPTION-LENGTH) in 184 octets and should be 4 plus the length of the EXTRA-TEXT section 185 (which may be a zero-length string). 186 o INFO-CODE, 16-bits, which is the principal contribution of this 187 document. This 16-bit value, encoded in network (MSB) byte order, 188 provides the additional context for the RESPONSE-CODE of the DNS 189 message. The INFO-CODE serves as an index into the "Extended DNS 190 Errors" registry Section 4.1. 191 o EXTRA-TEXT, a variable length, UTF-8 encoded, text field that may 192 hold additional textual information. Note: EXTRA-TEXT may be zero 193 octets in length, indicating there is no EXTRA-TEXT included. 194 Care should be taken not to leak private information that an 195 observer would not otherwise have access to, such as account 196 numbers. 198 The Extended DNS Error (EDE) option can be included in any response 199 (SERVFAIL, NXDOMAIN, REFUSED, and even NOERROR, etc) to a query that 200 includes OPT Pseudo-RR [RFC6891]. This document includes a set of 201 initial codepoints (and requests to the IANA to add them to the 202 registry), but is extensible via the IANA registry to allow 203 additional error and information codes to be defined in the future. 205 3. Defined Extended DNS Errors 207 This document defines some initial EDE codes. The mechanism is 208 intended to be extensible, and additional code-points can be 209 registered in the "Extended DNS Errors" registry Section 4.1. The 210 INFO-CODE from the EDE EDNS option is used to serve as an index into 211 the "Extended DNS Error" IANA registry, the initial values for which 212 are defined in the following sub-sections. 214 3.1. Extended DNS Error Code 0 - Other 216 The error in question falls into a category that does not match known 217 extended error codes. Implementations SHOULD include a EXTRA-TEXT 218 value to augment this error code with additional information. 220 3.2. Extended DNS Error Code 1 - Unsupported DNSKEY Algorithm 222 The resolver attempted to perform DNSSEC validation, but a DNSKEY 223 RRSET contained only unsupported DNSSEC algorithms. 225 3.3. Extended DNS Error Code 2 - Unsupported DS Digest Type 227 The resolver attempted to perform DNSSEC validation, but a DS RRSET 228 contained only unsupported Digest Types. 230 3.4. Extended DNS Error Code 3 - Stale Answer 232 The resolver was unable to resolve answer within its time limits and 233 decided to answer with previously cached data instead of answering 234 with an error. This is typically caused by problems communicating 235 with an authoritative serever, possibly as result of a DoS attack 236 against another network. 238 3.5. Extended DNS Error Code 4 - Forged Answer 240 For policy reasons (legal obligation, or malware filtering, for 241 instance), an answer was forged. Note that this should be used when 242 an answer is still provided, not when failure codes are returned 243 instead. See Blocked(15), Censored (16), and Filtered (17) for use 244 when returning other response codes. 246 3.6. Extended DNS Error Code 5 - DNSSEC Indeterminate 248 The resolver attempted to perform DNSSEC validation, but validation 249 ended in the Indeterminate state [RFC4035]. 251 3.7. Extended DNS Error Code 6 - DNSSEC Bogus 253 The resolver attempted to perform DNSSEC validation, but validation 254 ended in the Bogus state. 256 3.8. Extended DNS Error Code 7 - Signature Expired 258 The resolver attempted to perform DNSSEC validation, but no 259 signatures are presently valid and some (often all) are expired. 261 3.9. Extended DNS Error Code 8 - Signature Not Yet Valid 263 The resolver attempted to perform DNSSEC validation, but but no 264 signatures are presently valid and at least some are not yet valid. 266 3.10. Extended DNS Error Code 9 - DNSKEY Missing 268 A DS record existed at a parent, but no supported matching DNSKEY 269 record could be found for the child. 271 3.11. Extended DNS Error Code 10 - RRSIGs Missing 273 The resolver attempted to perform DNSSEC validation, but no RRSIGs 274 could be found for at least one RRset where RRSIGs were expected. 276 3.12. Extended DNS Error Code 11 - No Zone Key Bit Set 278 The resolver attempted to perform DNSSEC validation, but no Zone Key 279 Bit was set in a DNSKEY. 281 3.13. Extended DNS Error Code 12 - NSEC Missing 283 The resolver attempted to perform DNSSEC validation, but the 284 requested data was missing and a covering NSEC or NSEC3 was not 285 provided. 287 3.14. Extended DNS Error Code 13 - Cached Error 289 The resolver is returning the SERVFAIL RCODE from its cache. 291 3.15. Extended DNS Error Code 14 - Not Ready 293 The server is unable to answer the query as it is not fully 294 functional (yet). 296 3.16. Extended DNS Error Code 15 - Blocked 298 The server is unable to respond to the request because the domain is 299 blacklisted due to an internal security policy imposed by the 300 operator of the server being directly talked to. 302 3.17. Extended DNS Error Code 16 - Censored 304 The server is unable to respond to the request because the domain is 305 blacklisted by a security policy imposed upon the server being talked 306 to by an external requirement. Note that how the imposed policy is 307 applied is irrelevant (in-band DNS filtering, court order, etc). 309 3.18. Extended DNS Error Code 17 - Filtered 311 The server is unable to respond to the request because the domain is 312 blacklisted as requested by the client. Functionally, this amounts 313 to "you requested that we filter domains like this one." 315 3.19. Extended DNS Error Code 18 - Prohibited 317 An authoritative or recursive resolver that receives a query from an 318 "unauthorized" client can annotate its REFUSED message with this 319 code. Examples of "unauthorized" clients are recursive queries from 320 IP addresses outside the network, blacklisted IP addresses, local 321 policy, etc. 323 3.20. Extended DNS Error Code 19 - Stale NXDOMAIN Answer 325 The resolver was unable to resolve an answer within its configured 326 time limits and decided to answer with a previously cached NXDOMAIN 327 answer instead of answering with an error. This is may be caused, 328 for example, by problems communicating with an authoritative server, 329 possibly as result of a DoS attack against another network. 331 3.21. Extended DNS Error Code 20 - Not Authoritative 333 An authoritative server that receives a query (with the RD bit clear, 334 or when not configured for recursion) for a domain for which it is 335 not authoritative SHOULD include this EDE code in the REFUSED 336 response. A resolver that receives a query (with the RD bit clear) 337 SHOULD include this EDE code in the REFUSED response. 339 3.22. Extended DNS Error Code 21 - Not Supported 341 The requested operation or query is not supported as its use has been 342 deprecated. 344 3.23. Extended DNS Error Code 22 - No Reachable Authority 346 The resolver could not reach any of the authoritative name servers 347 (or they refused to reply). 349 3.24. Extended DNS Error Code 23 - Network Error 351 An unrecoverable error occurred while communicating with another 352 server. 354 3.25. Extended DNS Error Code 24 - Invalid Data 356 An authoritative server that cannot answer with data for a zone it is 357 otherwise configured to support. This may occur because its most 358 recent zone is too old, or has expired, for example. 360 4. IANA Considerations 362 4.1. A New Extended DNS Error Code EDNS Option 364 This document defines a new EDNS(0) option, entitled "Extended DNS 365 Error", assigned a value of TBD1 from the "DNS EDNS0 Option Codes 366 (OPT)" registry [to be removed upon publication: 367 [http://www.iana.org/assignments/dns-parameters/dns- 368 parameters.xhtml#dns-parameters-11] 370 Value Name Status Reference 371 ----- ---------------- ------ ------------------ 372 TBD Extended DNS Error TBD [ This document ] 374 4.2. New Registry Table for Extended DNS Error Codes 376 This document defines a new IANA registry table, where the index 377 value is the INFO-CODE from the "Extended DNS Error" EDNS option 378 defined in this document. The IANA is requested to create and 379 maintain this "Extended DNS Error" codes registry. The code-point 380 space for the INFO-CODE index is to be broken into 3 ranges: 382 o 0 - 32767: Expert Review [RFC2434]. 383 o 32768 - 49151: First come, first served. 384 o 49152 - 65535: Experimental / Private use. 386 A starting set of entries, based on the contents of this document, is 387 as follows: 389 INFO-CODE: 0 390 Purpose: Other Error 391 Reference: Section 3.1 393 INFO-CODE: 1 394 Purpose: Unsupported DNSKEY Algorithm 395 Reference: Section 3.2 397 INFO-CODE: 2 398 Purpose: Unsupported DS Digest Type 399 Reference: Section 3.3 401 INFO-CODE: 3 402 Purpose: Stale Answer 403 Reference: Section 3.4, [I-D.ietf-dnsop-serve-stale] 405 INFO-CODE: 4 406 Purpose: Forged Answer 407 Reference: Section 3.5 409 INFO-CODE: 5 410 Purpose: DNSSEC Indeterminate 411 Reference: Section 3.6 413 INFO-CODE: 6 414 Purpose: DNSSEC Bogus 415 Reference: Section 3.7 417 INFO-CODE: 7 418 Purpose: Signature Expired 419 Reference: Section 3.8 421 INFO-CODE: 8 422 Purpose: Signature Not Yet Valid 423 Reference: Section 3.9 425 INFO-CODE: 9 426 Purpose: DNSKEY Missing 427 Reference: Section 3.10 429 INFO-CODE: 10 430 Purpose: RRSIGs Missing 431 Reference: Section 3.11 433 INFO-CODE: 11 434 Purpose: No Zone Key Bit Set 435 Reference: Section 3.12 437 INFO-CODE: 12 438 Purpose: NSEC Missing 439 Reference: Section 3.13 441 INFO-CODE: 13 442 Purpose: Cached Error 443 Reference: Section 3.14 445 INFO-CODE: 14 446 Purpose: Not Ready. 447 Reference: Section 3.15 449 INFO-CODE: 15 450 Purpose: Blocked 451 Reference: Section 3.16 453 INFO-CODE: 16 454 Purpose: Censored 455 Reference: Section 3.17 457 INFO-CODE: 17 458 Purpose: Filtered 459 Reference: Section 3.18 461 INFO-CODE: 18 462 Purpose: Prohibited 463 Reference: Section 3.19 465 INFO-CODE: 19 466 Purpose: Stale NXDomain Answer 467 Reference: Section 3.20 469 INFO-CODE: 20 470 Purpose: Not Authoritative 471 Reference: Section 3.21 473 INFO-CODE: 21 474 Purpose: Not Supported 475 Reference: Section 3.22 477 INFO-CODE: 22 478 Purpose: No Reachable Authority 479 Reference: Section 3.23 481 INFO-CODE: 23 482 Purpose: Network Error 483 Reference: Section 3.24 485 INFO-CODE: 24 486 Purpose: Invalid Data 487 Reference: Section 3.25 489 5. Security Considerations 491 Though DNSSEC continues to be deployed, unfortunately a significant 492 number of clients (~11% according to [GeoffValidation]) that receive 493 a SERVFAIL from a validating resolver because of a DNSSEC validaion 494 issue will simply ask the next (potentially non-validating) resolver 495 in their list, and thus don't get any of the protections which DNSSEC 496 should provide. 498 This information is unauthenticated information, and an attacker (e.g 499 a MITM or malicious recursive server) could insert an extended error 500 response into already untrusted data -- ideally clients and resolvers 501 would not trust any unauthenticated information, but until we live in 502 an era where all DNS answers are authenticated via DNSSEC or other 503 mechanisms [RFC2845] [RFC8094], there are some tradeoffs. As an 504 example, an attacker who is able to insert the DNSSEC Bogus Extended 505 Error into a packet could instead simply reply with a fictitious 506 address (A or AAAA) record. Note that DNS Response Codes also 507 contain no authentication and can be just as easily manipulated. 509 6. Acknowledgements 511 The authors wish to thank Joe Abley, Mark Andrews, Tim April, 512 Vittorio Bertola, Stephane Bortzmeyer, Vladimir Cunat, Ralph Dolmans, 513 Peter DeVries, Peter van Dijk, Mats Dufberg, Donald Eastlake, Bob 514 Harold, Paul Hoffman, Geoff Huston, Shane Kerr, Edward Lewis, Carlos 515 M. Martinez, George Michelson, Eric Orth, Michael Sheldon, Puneet 516 Sood, Petr Spacek, Ondrej Sury, John Todd, Loganaden Velvindron, and 517 Paul Vixie. They also vaguely remember discussing this with a number 518 of people over the years, but have forgotten who all they were -- if 519 you were one of them, and are not listed, please let us know and 520 we'll acknowledge you. 522 One author also wants to thank the band "Infected Mushroom" for 523 providing a good background soundtrack (and to see if he can get away 524 with this in an RFC!) Another author would like to thank the band 525 "Mushroom Infectors". This was funny at the time we wrote it, but we 526 cannot remember why... 528 7. References 530 7.1. Normative References 532 [I-D.ietf-dnsop-serve-stale] 533 Lawrence, D., Kumari, W., and P. Sood, "Serving Stale Data 534 to Improve DNS Resiliency", draft-ietf-dnsop-serve- 535 stale-08 (work in progress), September 2019. 537 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 538 Requirement Levels", BCP 14, RFC 2119, 539 DOI 10.17487/RFC2119, March 1997, . 542 [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an 543 IANA Considerations Section in RFCs", RFC 2434, 544 DOI 10.17487/RFC2434, October 1998, . 547 [RFC2671] Vixie, P., "Extension Mechanisms for DNS (EDNS0)", 548 RFC 2671, DOI 10.17487/RFC2671, August 1999, 549 . 551 [RFC4035] Arends, R., Austein, R., Larson, M., Massey, D., and S. 552 Rose, "Protocol Modifications for the DNS Security 553 Extensions", RFC 4035, DOI 10.17487/RFC4035, March 2005, 554 . 556 [RFC6891] Damas, J., Graff, M., and P. Vixie, "Extension Mechanisms 557 for DNS (EDNS(0))", STD 75, RFC 6891, 558 DOI 10.17487/RFC6891, April 2013, . 561 7.2. Informative References 563 [GeoffValidation] 564 IANA, "A quick review of DNSSEC Validation in today's 565 Internet", June 2016, . 568 [RFC2845] Vixie, P., Gudmundsson, O., Eastlake 3rd, D., and B. 569 Wellington, "Secret Key Transaction Authentication for DNS 570 (TSIG)", RFC 2845, DOI 10.17487/RFC2845, May 2000, 571 . 573 [RFC8094] Reddy, T., Wing, D., and P. Patil, "DNS over Datagram 574 Transport Layer Security (DTLS)", RFC 8094, 575 DOI 10.17487/RFC8094, February 2017, . 578 Authors' Addresses 580 Warren Kumari 581 Google 582 1600 Amphitheatre Parkway 583 Mountain View, CA 94043 584 US 586 Email: warren@kumari.net 588 Evan Hunt 589 ISC 590 950 Charter St 591 Redwood City, CA 94063 592 US 594 Email: each@isc.org 596 Roy Arends 597 ICANN 599 Email: roy.arends@icann.org 601 Wes Hardaker 602 USC/ISI 603 P.O. Box 382 604 Davis, CA 95617 605 US 607 Email: ietf@hardakers.net 608 David C Lawrence 609 Oracle + Dyn 610 150 Dow St 611 Manchester, NH 03101 612 US 614 Email: tale@dd.org