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Crocker 3 Internet-Draft Brandenburg InternetWorking 4 Intended status: Best Current Practice March 29, 2017 5 Expires: September 30, 2017 7 DNS Scoped Data Through Global '_Underscore' Naming of Attribute Leaves 8 draft-ietf-dnsop-attrleaf-02 10 Abstract 12 Formally, any DNS "RR" may occur for any domain name. However some 13 services have defined an operational convention that applies to DNS 14 leaf nodes that have a reserved node name, beginning with an 15 underscore. The underscore construct is used to define a semantic 16 scope for DNS records that are associated with the parent domain. 17 This specification explores the nature of this DNS usage and defines 18 the "DNS Global Underscore Scoped Entry Registry" registry with IANA. 20 Status of This Memo 22 This Internet-Draft is submitted in full conformance with the 23 provisions of BCP 78 and BCP 79. 25 Internet-Drafts are working documents of the Internet Engineering 26 Task Force (IETF). Note that other groups may also distribute 27 working documents as Internet-Drafts. The list of current Internet- 28 Drafts is at http://datatracker.ietf.org/drafts/current/. 30 Internet-Drafts are draft documents valid for a maximum of six months 31 and may be updated, replaced, or obsoleted by other documents at any 32 time. It is inappropriate to use Internet-Drafts as reference 33 material or to cite them other than as "work in progress." 35 This Internet-Draft will expire on September 30, 2017. 37 Copyright Notice 39 Copyright (c) 2017 IETF Trust and the persons identified as the 40 document authors. All rights reserved. 42 This document is subject to BCP 78 and the IETF Trust's Legal 43 Provisions Relating to IETF Documents 44 (http://trustee.ietf.org/license-info) in effect on the date of 45 publication of this document. Please review these documents 46 carefully, as they describe your rights and restrictions with respect 47 to this document. Code Components extracted from this document must 48 include Simplified BSD License text as described in Section 4.e of 49 the Trust Legal Provisions and are provided without warranty as 50 described in the Simplified BSD License. 52 Table of Contents 54 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 55 2. Scaling Benefits and TXT and SRV Resource Records . . . . . . 3 56 3. DNS Global Underscore Scoped Entry Registry Function . . . . 4 57 4. DNS Global Underscore Scoped Entry Registry Definition . . . 5 58 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 59 6. Related and Updated Registries . . . . . . . . . . . . . . . 9 60 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9 61 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 62 8.1. Normative References . . . . . . . . . . . . . . . . . . 9 63 8.2. References -- Informative . . . . . . . . . . . . . . . . 9 64 8.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 12 65 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 12 66 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 12 68 1. Introduction 70 The core DNS technical specifications assign no semantics to domain 71 names or their parts, and no constraints upon which resource records 72 (RRs) are permitted to be associated with particular names. Over 73 time, some leaf node names, such as "www" and "ftp" have come to 74 imply support for particular services, but this is a matter of 75 operational convention, rather than defined protocol semantics. This 76 freedom in the basic technology has permitted a wide range of 77 administrative and semantic policies to be used -- in parallel. Data 78 semantics have been limited to the specification of particular 79 resource records, on the expectation that new ones would be added as 80 needed. 82 As an alternative to defining new RRs, some DNS service enhancements 83 reuse an existing resource record, but have specified a restricted 84 scope for its occurrence. That scope is a leaf node, within which 85 the uses of specific resource records can be formally defined and 86 constrained. The leaf has a distinguished naming convention: It uses 87 a reserved DNS node name that begins with an underscore ("_"). 88 Because the DNS rules for a "host" (host name) are not allowed to use 89 the underscore character, this distinguishes the underscore name from 90 all legal host names [RFC1035]. Effectively, this convention for 91 leaf node naming creates a space for attributes that are associated 92 with the parent domain, one level up. 94 One example is the "SRV" record [RFC2782] which generalizes concepts 95 long-used for email routing by the "MX" record [RFC0974][RFC5321]. 96 An equivalent usage to "SRV" is the "URI" "RR" [RFC7553]. Relying on 97 special DNS names has significant benefits and detriments. Some of 98 these are explored in [RFC5507]. 100 [Comment]: The terms "resolution context" and "scoping rules" have 101 been suggested, in place of "semantic scope". In order to avoid 102 concern for matters of semantics, this specification uses the term 103 "scoping rules", to create a focus on the mechanics being defined, 104 rather than nuances of interpretation for the mechanism. 106 The scoping feature is particularly useful when generalized resource 107 records are used -- notably "TXT", "SRV" and "URI". It provides 108 efficient separation of one use of them from others. Absent this 109 separation, an undifferentiated mass of these "RR"s is returned to 110 the DNS client, which then must parse through the internals of the 111 records in the hope of finding ones that are relevant. Worse, in 112 some cases the results are ambiguous because the records do not 113 adequately self-identify. With underscore-based scoping, only the 114 relevant "RR"s are returned. 116 This specification discusses the underscore "attribute" enhancement, 117 provides an explicit definition of it, and establishes an IANA 118 registry for the highest-level reserved names that begin with 119 _underscore; underscore-based names that are farther down the 120 hierarchy is handled within the scope of the highest-level 121 _underscore name. It updates the many existing specifications that 122 have defined underscore names, in order to aggregate the references 123 to a single IANA table. 125 Discussion Venue: Discussion about this draft should be directed 126 to the dnsop@ietf.org [1] mailing list. 128 2. Scaling Benefits and TXT and SRV Resource Records 130 Some resource records are generic and support a variety of uses. 131 Each additional use defines its own rules and, possibly, its own 132 internal syntax and node-naming conventions to distinguish among 133 particular types. The "TXT" and "SRV" records are notable examples. 134 Used freely, some of these approaches scale poorly, particularly when 135 the same "RR" can be present in the same leaf node, but with 136 different uses. An increasingly-popular approach, with excellent 137 scaling properties, uses an underscore-based name, at a defined place 138 in the DNS tree, so as to constrain to particular uses for particular 139 "RR"s farther down the branch using that name. This means that a 140 direct lookup produces only the desired records, at no greater cost 141 than a typical DNS lookup. 143 In the case of "TXT" records, different uses have developed largely 144 without coordination. One side-effect is that there is no 145 consistently distinguishable internal syntax for the record; even the 146 inefficiencies of internal inspection might not provide a reliable 147 means of distinguishing among the different uses. Underscore-based 148 names therefore define an administrative way of separating "TXT" 149 records that might have different uses, but otherwise would have no 150 syntactic markers for distinguishing among them. 152 In the case of the "SRV" "RR" and "URI" "RR", distinguishing among 153 different types of use was part of the design [RFC2782], [RFC7553]. 154 The "SRV" and "URI" specifications serve as templates, defining "RR"s 155 that might only be used for specific applications when there is an 156 additional specification. The template definition includes reference 157 to two levels of tables of names from which underscore-names should 158 be drawn. The lower-level (local scope) set of <"_service"> names is 159 defined in terms of other IANA tables, namely any table with symbolic 160 names. The upper-level (global scope) "SRV" naming field is 161 <"_proto">, although its pool of names is not explicitly defined. 163 The current definition of a global underscore registry attends only 164 to the "upper-level" names used for these RRs, that is the "_proto" 165 names. 167 3. DNS Global Underscore Scoped Entry Registry Function 169 This specification creates a registry for DNS nodes names that begin 170 with an underscore and are used to define scope of use for specific 171 resource records. A given name defines a specific, constrained 172 context for the use of such records. Within this scope, use of other 173 resource records that are not specified is permitted. The purpose of 174 the Underscore registry is to avoid collisions resulting from the use 175 of the same underscore-based name, for different applications. 177 Structurally, the registry is defined as a single, flat table of 178 names that begin with underscore. In some cases, such as for "SRV", 179 an underscore name might be multi-part, as a sequence of underscore 180 names. Semantically, that sequence represents a hierarchical model 181 and it is theoretically reasonable to allow re-use of an underscore 182 name in different underscore context; a subordinate name is 183 meaningful only within the scope of the first (parent) underscore 184 name. As such, they can be ignored by this DNS Global Underscore 185 Scoped Entry Registry. That is, the registry is for the definition 186 of highest-level underscore node name used. 188 +---+ 190 +----------------------------+ 191 | NAME | 192 +----------------------------+ 193 | _service1 | 194 | ._protoB._service2 | 195 | _protoB._service3 | 196 | _protoC._service3 | 197 | _useX._protoD._service4 | 198 | _protoE._region._authority | 199 +----------------------------+ 201 Example of Underscore Names 203 Only the right-most names are registered in the IANA Underscore 204 table. Definition and registration of the subordinate names is the 205 responsibility of the specification that creates the highest-level 206 (right-most) registry entry. 208 4. DNS Global Underscore Scoped Entry Registry Definition 210 A registry entry contains: 212 Name: Specifies a textual name for a scoped portion of the DNS. 213 The name will usually be taken from the specification cited in 214 the "Purpose" column and is intended for use in discussions 215 about the entry. 217 DNS Label: Specifies a single _underscore name that defines a 218 name reservation; this name is the "global" entry name for the 219 scoped resource records that are associated with that name. 221 Constraints: Specifies any restrictions on use of the name. 223 RR(s): Lists the RRs that are defined for use within this 224 scope. 226 References Lists specifications that define the records and their 227 use under this Name. 229 Purpose: Specifies the particular purpose/use for specific 230 "RR"(s), defined for use within the scope of the registered 231 underscore name. 233 5. IANA Considerations 235 Per [RFC5226], IANA is requested to establish a DNS Global Underscore 236 Scoped Entry Registry, for DNS node names that begin with the 237 underscore character (_) and have been specified in any published 238 RFC, or are documented by a specification published by another 239 standards organization. The contents of each entry are defined in 240 Section 4. 242 Initial entries in the registry are: 244 { Enhancement of this table to include all underscore name 245 reservations in effect at the time this document is published is 246 left as an exercise to the readers... /d } 248 +------------+--------------+-------+-----------+-------------------+ 249 | NAME | LABEL | RR | REFERENCE | PURPOSE | 250 +------------+--------------+-------+-----------+-------------------+ 251 | "SRV" | _srv | "SRV" | [RFC2782] | "SRV" template -- | 252 | | | | | pro forma entry, | 253 | | | | | not directly | 254 | | | | | usable | 255 | "SRV" TCP | _tcp | "SRV" | [RFC2782] | Use of "SRV" for | 256 | | | | | a TCP-based | 257 | | | | | service | 258 | "SRV" UDP | _udp | "SRV" | [RFC2782] | Use of "SRV" for | 259 | | | | | a UDP-based | 260 | | | | | service | 261 | LDAP | _ldap | "SRV" | [RFC2782] | LDAP server | 262 | SIP | _sip | NAPTR | [RFC3263] | Locating SIP | 263 | | | | [RFC6011] | Servers and UA | 264 | | | | | configuration | 265 | SPF | _spf | "TXT" | [RFC7372] | Authorized IP | 266 | | | | | addresses for | 267 | | | | | sending mail | 268 | DKIM | _domainkey | "TXT" | [RFC6376] | Public key for | 269 | | | | | verifying DKIM | 270 | | | | | signature. | 271 | PKI LDAP | _PKIXREP | "SRV" | [RFC4386] | PKI Repository | 272 | VBR | _vouch | "TXT" | [RFC5518] | Vouch-by- | 273 | | | | | refererence | 274 | | | | | domain assertion | 275 | DDDS | --???!-- | "SRV" | [RFC3404] | Mapping DDDS | 276 | | | | | query to DNS | 277 | | | | | records | 278 | SOAP BEEP | _soap-beep | "SRV" | [RFC4227] | SOAP over BEEP | 279 | | | | | lookup, when no | 280 | | | | | port specified | 281 | XMLRPC | _xmlrpc-beep | "SRV" | [RFC3529] | Resolve url for | 282 | BEEP | | | | XML-RPC using | 283 | | | | | BEEP | 284 | Diameter | _diameter | "SRV" | [RFC6733] | Diameter | 285 | | | | | rendezvous | 286 | Tunnel | _tunnel | "SRV" | [RFC3620] | Finding the | 287 | | | | | appropriate | 288 | | | | | address for | 289 | | | | | tunneling into a | 290 | | | | | particular domain | 291 | SLP | _slpda | "SRV" | [RFC3832] | Discovering | 292 | | | | | desired services | 293 | | | | | in given DNS | 294 | | | | | domains | 295 | Msg Track | _mtqp | "SRV" | [RFC3887] | Assist in | 296 | | | | | determining the | 297 | | | | | path that a | 298 | | | | | particular | 299 | | | | | message has taken | 300 | | | | | through a | 301 | | | | | messaging system | 302 | XMPP | _xmpp-client | "SRV" | [RFC6120] | XMPP client | 303 | Client | | | | lookup of server | 304 | XMPP | _xmpp-server | "SRV" | [RFC6120] | XMPP server- | 305 | Server | | | | server lookup | 306 | DDDS "SRV" | _??? | "SRV" | [RFC3958] | Map domain name, | 307 | | | (and | | application | 308 | | | NAPTR | | service name, and | 309 | | | ?) | | application | 310 | | | | | protocol | 311 | | | | | dynamically to | 312 | | | | | target server and | 313 | | | | | port | 314 | Kerberos | _kerberos | "SRV" | [RFC4120] | purpose | 315 | PKI | _pkixrep | "SRV" | [RFC4386] | Enables | 316 | | | | | certificate-using | 317 | | | | | systems to locate | 318 | | | | | PKI repositories | 319 | Certificat | _certificate | "SRV" | [RFC4387] | Obtain | 320 | es | s | | | certificates and | 321 | | | | | certificate | 322 | | | | | revocation lists | 323 | | | | | (CRLs) from PKI | 324 | | | | | repositories | 325 | PGP Key | _pgpkeys | "SRV" | [RFC4387] | Obtain | 326 | Store | | | | certificates and | 327 | | | | | certificate | 328 | | | | | revocation lists | 329 | | | | | (CRLs) from PKI | 330 | | | | | repositories | 331 | MSRP Relay | _msrp | "SRV" | [RFC4976] | purpose | 332 | Locator | | | | | 333 | Mobile | _mip6 | "SRV" | [RFC5026] | Bootstrap Mobile | 334 | IPv6 | | | [RFC5555] | IPv6 Home Agent | 335 | Bootstrap | | | | information from | 336 | | | | | non-topological | 337 | | | | | information | 338 | Digital | _dvbservdsc | "SRV" | [RFC5328] | Discover non- | 339 | Video Broa | | | | default DVB entry | 340 | dcasting | | | | points addresses | 341 | CAPWAP AC | _capwap- | rrs | [RFC5415] | Discover the | 342 | | control | | | CAPWAP AC | 343 | | | | | address(es) | 344 | IEEE | _mihis | NAPTR | [RFC5679] | Discovering | 345 | 802.21 | | , | | servers that | 346 | Mobility | | "SRV" | | provide IEEE | 347 | | | | | 802.21-defined | 348 | | | | | Mobility Services | 349 | STUN Clien | _stun | "SRV" | [RFC5389] | Find a STUN | 350 | t/Server | | | | server | 351 | TURN | _turn | "SRV" | [RFC5766] | Control the | 352 | | | | [RFC5928] | operation of a | 353 | | | | | relay to bypass | 354 | | | | | NAT | 355 | STUN NAT | _stun- | "SRV" | [RFC5780] | Discover the | 356 | Behavior | behavior | | | presence and | 357 | Discovery | | | | current behavior | 358 | | | | | of NATs and | 359 | | | | | firewalls between | 360 | | | | | the STUN client | 361 | | | | | and the STUN | 362 | | | | | server | 363 | Sieve | _sieve | "SRV" | [RFC5804] | Manage Sieve | 364 | Management | | | | scripts on a | 365 | | | | | remote server | 366 | AFS VLDB | _afs3-vlserv | "SRV" | [RFC5864] | Locate services | 367 | | er | | | for the AFS | 368 | | | | | distributed file | 369 | | | | | system | 370 | AFS PTS | _afs3-prserv | "SRV" | [RFC5864] | Locate services | 371 | | er | | | for the AFS | 372 | | | | | distributed file | 373 | | | | | system | 374 | Mail MSA | _submission | "SRV" | [RFC6186] | Locate email | 375 | Submission | | | | services | 376 | IMAP | _imap | "SRV" | [RFC6186] | Locate email | 377 | | | | | services | 378 | POP | _pop3 | "SRV" | [RFC6186] | Locate email | 379 | | | | | services | 380 | POP TLS | _pop3s | "SRV" | [RFC6186] | Locate email | 381 | | | | | services | 382 +------------+--------------+-------+-----------+-------------------+ 384 Table 1: DNS Global Underscore Scoped Entry Registry (with initial 385 values) 387 6. Related and Updated Registries 389 This section needs to contained details specification of the 390 updates to existing underscore "registries", in order to have 391 those specifications point to this new registry. 393 Numerous specifications have defined their own, independent 394 registries for use of underscore names. It is likely that adoption 395 of the proposed, integrated registry should render these piecemeal 396 registries obsolete 398 Registries that are candidates for replacement include: 400 Instant Messaging "SRV" Protocol Label Registry 402 Public Key Infrastructure using X.509 (PKIX) Parameters 404 Presence "SRV" Protocol Label Registry 406 7. Security Considerations 408 This memo raises no security issues. 410 8. References 412 8.1. Normative References 414 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 415 IANA Considerations Section in RFCs", RFC 5226, May 2008. 417 8.2. References -- Informative 419 [RFC0974] Partridge, C., "Mail routing and the domain system", 420 RFC 974, January 1986. 422 [RFC1035] Mockapetris, P., "Domain names - implementation and 423 specification", STD 13, RFC 1035, November 1987. 425 [RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for 426 specifying the location of services (DNS SRV)", RFC 2782, 427 February 2000. 429 [RFC3263] Rosenberg, J. and H. Schulzrinne, "Session Initiation 430 Protocol (SIP): Locating SIP Servers", RFC 3263, June 431 2002. 433 [RFC3404] MMealling, M., "Dynamic Delegation Discovery System (DDDS) 434 Part Four: The Uniform Resource Identifiers (URI) 435 Resolution Application", RFC 3404, October 2002. 437 [RFC3529] Harold, W., "Using Extensible Markup Language-Remote 438 Procedure Calling (XML-RPC) in Blocks Extensible Exchange 439 Protocol (BEEP)", RFC 3529, April 2003. 441 [RFC3620] New, D., "The TUNNEL Profile", RFC 3620, October 2003. 443 [RFC3832] Columbia University, Columbia University, Sun 444 Microsystems, IBM, and IBM, "Remote Service Discovery in 445 the Service Location Protocol (SLP) via DNS SRV", 446 RFC 3832, July 2004. 448 [RFC3887] "Message Tracking Query Protocol", RFC 3887, September 449 2007. 451 [RFC3958] Daigle, L. and A. Newton, "Domain-Based Application 452 Service Location Using SRV RRs and the Dynamic Delegation 453 Discovery Service (DDDS)", RFC 3958, January 2005. 455 [RFC4120] USC-ISI, MIT, MIT, and MIT, "The Kerberos Network 456 Authentication Service (V5)", RFC 4120, July 2005. 458 [RFC4227] O'Tuathail, E. and M. Rose, "Using the Simple Object 459 Access Protocol (SOAP) in Blocks Extensible Exchange 460 Protocol (BEEP)", RFC 4227, January 2006. 462 [RFC4386] Boeyen, S. and P. Hallam-Baker, "Internet X.509 Public Key 463 Infrastructure: Repository Locator Service", RFC 4386, 464 February 2006. 466 [RFC4387] Gutmann, P., Ed., "Internet X.509 Public Key 467 Infrastructure Operational Protocols: Certificate Store 468 Access via HTTP", RFC 4387, February 2006. 470 [RFC4976] Jennings, C., Mahy, R., and Roach, "Relay Extensions for 471 the Message Session Relay Protocol (MSRP)", RFC 4976, 472 September 2007. 474 [RFC5026] Giaretta, G., Ed., Kempf, J., and V. Devarapalli, Ed., 475 "Mobile IPv6 Bootstrapping in Split Scenario", RFC 5026, 476 October 2007. 478 [RFC5321] Klensin, J., "Simple Mail Transfer Protocol", RFC 5321, 479 Oct 2008. 481 [RFC5328] Adolf, A. and P. MacAvock, "A Uniform Resource Name (URN) 482 Namespace for the Digital Video Broadcasting Project 483 (DVB)", RFC 5328, September 2008. 485 [RFC5389] Rosenberg, , Mahy, , Matthews, , and Wing, "Session 486 Traversal Utilities for NAT (STUN)", RFC 5389, October 487 2008. 489 [RFC5415] Calhoun, P., Ed., Montemurro, M., Ed., and D. Stanley, 490 Ed., "Control And Provisioning of Wireless Access Points 491 (CAPWAP) Protocol Specification", RFC 5415, March 2009. 493 [RFC5507] Faltstrom, P., Ed. and R. Austein, Ed., "Design Choices 494 When Expanding the DNS", RFC 5507, April 2009. 496 [RFC5518] Hoffman, P., Levine, J., and A. Hathcock, "Vouch By 497 Reference", RFC 5518, April 2009. 499 [RFC5555] Soliman, H., Ed., "Mobile IPv6 Support for Dual Stack 500 Hosts and Routers", RFC 5555, June 2009. 502 [RFC5679] Bajko, G., "Locating IEEE 802.21 Mobility Services Using 503 DNS", RFC 5679, December 2009. 505 [RFC5766] Mahy, R., Matthews, P., and J. Rosenberg, "Traversal Using 506 Relays around NAT (TURN): Relay Extensions to Session 507 Traversal Utilities for NAT (STUN)", RFC 5766, April 2010. 509 [RFC5780] MacDonald, D. and B. Lowekamp, "NAT Behavior Discovery 510 Using Session Traversal Utilities for NAT (STUN)", 511 RFC 5780, May 2010. 513 [RFC5804] Melnikov, A., Ed. and T. Martin, "A Protocol for Remotely 514 Managing Sieve Scripts", RFC 5804, July 2010. 516 [RFC5864] Allbery, R., "NS SRV Resource Records for AFS", RFC 5864, 517 April 2010. 519 [RFC5928] Petit-Huguenin, M., "Traversal Using Relays around NAT 520 (TURN) Resolution Mechanism", RFC 5928, August 2010. 522 [RFC6011] Lawrence, S., Ed. and J. Elwell, "Session Initiation 523 Protocol (SIP) User Agent Configuration", RFC 6011, 524 October 2010. 526 [RFC6120] Saint-Andre, P., "Extensible Messaging and Presence 527 Protocol (XMPP): Core", RFC 6120, March 2011. 529 [RFC6186] Daboo, C., "Use of SRV Records for Locating Email 530 Submission/Access Services", RFC 6186, March 2011. 532 [RFC6376] Crocker, D., Hansen, T., and M. Kucherawy, "DomainKeys 533 Identified Mail (DKIM) Signatures", RFC 6376, Sept 2011. 535 [RFC6733] Fajardo, V., Arkko, J., Loughney, J., and G. Zorn, 536 "Diameter Base Protocol", RFC 6733, October 2012. 538 [RFC7372] Kitterman, S., "Sender Policy Framework (SPF) for 539 Authorizing Use of Domains in E-Mail, Version 1", 540 RFC 7372, April 2014. 542 [RFC7553] Falstrom, P. and O. Kolkman, "The Uniform Resource 543 Identifier (URI) DNS Resource Record", RFC RFC7553, 544 ISSN 2070-1721, June 2015. 546 8.3. URIs 548 [1] mailto:dnsop@ietf.org 550 Appendix A. Acknowledgements 552 Thanks go to Bill Fenner, Tony Hansen, Peter Koch, Olaf Kolkman, and 553 Andrew Sullivan for diligent review of the (much) earlier drafts. 554 For the later enhancements, thanks to: Tim Wicinski, John Levine, Bob 555 Harold, Joel Jaeggli, Ondřej Sury and Paul Wouters. Special 556 thanks to Ray Bellis for more than 10 years of persistent 557 encouragement to continue this effort, as well as the suggestion for 558 an essential simplification to the registration model. 560 Author's Address 561 Dave Crocker 562 Brandenburg InternetWorking 563 675 Spruce Dr. 564 Sunnyvale, CA 94086 565 USA 567 Phone: +1.408.246.8253 568 Email: dcrocker@bbiw.net 569 URI: http://bbiw.net/