From 5178281071c1df5fc22e6c360ad611075de3074e Mon Sep 17 00:00:00 2001 From: Andreas Gustafsson Date: Fri, 7 Jul 2000 23:24:06 +0000 Subject: [PATCH] added draft-ietf-dnsext-message-size-00.txt; updated draft-ietf-dnsext-iana-dns* from -00 to -01 --- ....txt => draft-ietf-dnsext-iana-dns-01.txt} | 391 ++++++++++-------- .../draft-ietf-dnsext-message-size-00.txt | 282 +++++++++++++ 2 files changed, 506 insertions(+), 167 deletions(-) rename doc/draft/{draft-ietf-dnsext-iana-dns-00.txt => draft-ietf-dnsext-iana-dns-01.txt} (74%) create mode 100644 doc/draft/draft-ietf-dnsext-message-size-00.txt diff --git a/doc/draft/draft-ietf-dnsext-iana-dns-00.txt b/doc/draft/draft-ietf-dnsext-iana-dns-01.txt similarity index 74% rename from doc/draft/draft-ietf-dnsext-iana-dns-00.txt rename to doc/draft/draft-ietf-dnsext-iana-dns-01.txt index 84116106bc..95dc70dd5a 100644 --- a/doc/draft/draft-ietf-dnsext-iana-dns-00.txt +++ b/doc/draft/draft-ietf-dnsext-iana-dns-01.txt @@ -1,23 +1,22 @@ - INTERNET-DRAFT Donald E. Eastlake 3rd Eric Brunner Bill Manning -Expires: June 2000 February 2000 +Expires: December 2000 June 2000 Domain Name System (DNS) IANA Considerations ------ ---- ------ ----- ---- -------------- - + Status of This Document - Distribution of this draft , which - is intended to become a Best Current Practice, is unlimited. Comments - should be sent to the DNS Working Group mailing list - or to the authors. + Distribution of this draft, which is intended to become a Best + Current Practice, is unlimited. Comments should be sent to the DNS + Working Group mailing list or to the + authors. This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working @@ -25,11 +24,10 @@ Status of This Document and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. - Internet-Drafts are draft documents valid for a maximum of six - months. Internet-Drafts may be updated, replaced, or obsoleted by - other documents at any time. It is not appropriate to use Internet- - Drafts as reference material or to cite them other than as a - ``working draft'' or ``work in progress.'' + Internet-Drafts are draft documents valid for a maximum of six months + and may be updated, replaced, or obsoleted by other documents at any + time. It is inappropriate to use Internet- Drafts as reference + material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt @@ -54,10 +52,11 @@ Abstract + D. Eastlake 3rd, E. Brunner, B. Manning [Page 1] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 Table of Contents @@ -72,17 +71,17 @@ Table of Contents 2.1 One Spare Bit?.........................................4 2.2 Opcode Assignment......................................4 2.3 RCODE Assignment.......................................5 - 3. DNS Resource Records....................................5 + 3. DNS Resource Records....................................6 3.1 RR TYPE IANA Considerations............................7 3.1.1 Special Note on the OPT RR...........................8 3.2 RR CLASS IANA Considerations...........................8 3.3 RR NAME Considerations.................................9 - 4. Designated Expert......................................10 - 5. Security Considerations................................10 - References................................................10 + 4. Security Considerations................................10 - Authors Addresses.........................................12 - Expiration and File Name..................................12 + References................................................11 + + Authors Addresses.........................................13 + Expiration and File Name..................................13 @@ -115,7 +114,7 @@ Table of Contents D. Eastlake 3rd, E. Brunner, B. Manning [Page 2] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 1. Introduction @@ -136,8 +135,8 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 query/response opcode for such considerations if they have been defined. - IANA currently maintains a web page of DNS parameters at - . + IANA currently maintains a web page of DNS parameters. See + . "IETF Standards Action", "IETF Consensus", "Specification Required", and "Private Use" are as defined in [RFC 2434]. @@ -173,7 +172,7 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 D. Eastlake 3rd, E. Brunner, B. Manning [Page 3] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 The QR bit indicates whether the header is for a query or a response. @@ -231,7 +230,7 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 D. Eastlake 3rd, E. Brunner, B. Manning [Page 4] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 2.3 RCODE Assignment @@ -239,34 +238,43 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 It would appear from the DNS header above that only four bits of RCODE, or response/error code are available. However, RCODEs can appear not only at the top level of a DNS response but also inside - TSIG RRs [RFC XXX3] and OPT RRs [RFC 2671]. The OPT RR provides an - eight bit extension resulting in a 12 bit RCODE field and the TSIG RR - has a 16 bit RCODE field. + OPT RRs [RFC 2671], TSIG RRs [RFC 2845], and TKEY RRs [draft-ietf- + dnsext-tkey-*.txt]. The OPT RR provides an eight bit extension + resulting in a 12 bit RCODE field and the TSIG and TKEY RRs have a 16 + bit RCODE field. - RCODE Name Description Reference + Error codes appearing in the DNS header and in these three RR types + all refer to the same error code space with the single exception of + error code 16 which has a different meaning in the OPT RR from its + meaning in other contexts. See table below. + + RCODE Name Description Reference Decimal Hexadecimal - 0 NoError No Error [RFC 1035] - 1 FormErr Format Error [RFC 1035] - 2 ServFail Server Failure [RFC 1035] - 3 NXDomain Non-Existent Domain [RFC 1035] - 4 NotImp Not Implemented [RFC 1035] - 5 Refused Query Refused [RFC 1035] - 6 YXDomain Name Exists when it should not [RFC 2136] - 7 YXRRSet RR Set Exists when it should not [RFC 2136] - 8 NXRRSet RR Set that should exist does not [RFC 2136] - 9 NotAuth Server Not Authoritative for zone [RFC 2136] - 10 NotZone Name not contained in zone [RFC 2136] - 11-15 available for assignment - 16 BADVERS Bad OPT Version [RFC 2671] - 16 BADSIG TSIG Signature Failure [RFC XXX3] - 17 BADKEY Key not recognized [RFC XXX3] - 18 BADTIME Signature out of time window [RFC XXX3] - 19-3840 available for assignment - 0x0013-0x0F00 - 3841-4095 Private Use + 0 NoError No Error [RFC 1035] + 1 FormErr Format Error [RFC 1035] + 2 ServFail Server Failure [RFC 1035] + 3 NXDomain Non-Existent Domain [RFC 1035] + 4 NotImp Not Implemented [RFC 1035] + 5 Refused Query Refused [RFC 1035] + 6 YXDomain Name Exists when it should not [RFC 2136] + 7 YXRRSet RR Set Exists when it should not [RFC 2136] + 8 NXRRSet RR Set that should exist does not [RFC 2136] + 9 NotAuth Server Not Authoritative for zone [RFC 2136] + 10 NotZone Name not contained in zone [RFC 2136] + 11-15 available for assignment + 16 BADVERS Bad OPT Version [RFC 2671] + 16 BADSIG TSIG Signature Failure [RFC 2845] + 17 BADKEY Key not recognized [RFC 2845] + 18 BADTIME Signature out of time window [RFC 2845] + 19 BADMODE Bad TKEY Mode [draft-ietf-dnsext-tkey-*.txt] + 20 BADNAME Duplicate key name [draft-ietf-dnsext-tkey-*.txt] + 21 BADALG Algorithm not supported [draft-ietf-dnsext-tkey-*.txt] + 22-3840 available for assignment + 0x0016-0x0F00 + 3841-4095 Private Use 0x0F01-0x0FFF - 4096-65535 available for assignment + 4096-65535 available for assignment 0x1000-0xFFFF Since it is important that RCODEs be understood for interoperability, @@ -275,23 +283,19 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 -3. DNS Resource Records - - All RRs have the same top level format shown in the figure below - taken from [RFC 1035]: - - - - - D. Eastlake 3rd, E. Brunner, B. Manning [Page 5] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 +3. DNS Resource Records + + All RRs have the same top level format shown in the figure below + taken from [RFC 1035]: + 1 1 1 1 1 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ @@ -339,15 +343,10 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 - - - - - D. Eastlake 3rd, E. Brunner, B. Manning [Page 6] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 3.1 RR TYPE IANA Considerations @@ -366,7 +365,7 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 TYPE. There are currently three Meta-TYPEs assigned: OPT [RFC 2671], TSIG - [RFC XXX3], and TKEY [work in progress]. + [RFC 2845], and TKEY [draft-ietf-dnsext-tkey-*.txt]. There are currently five QTYPEs assigned: * (all), MAILA, MAILB, AXFR, and IXFR. @@ -405,7 +404,7 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 D. Eastlake 3rd, E. Brunner, B. Manning [Page 7] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 3.1.1 Special Note on the OPT RR @@ -448,10 +447,10 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 0x0002 - available for assignment by IETF Consensus as a data CLASS. 3 - 0x0003 - Chaos (CH) [Moon 81]. + 0x0003 - Chaos (CH) [Moon 1981]. 4 - 0x0004 - Hesiod (HS) [Dyer 87]. + 0x0004 - Hesiod (HS) [Dyer 1987]. 5 - 127 0x0005 - 0x007F - available for assignment by IETF Consensus as data @@ -463,7 +462,7 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 D. Eastlake 3rd, E. Brunner, B. Manning [Page 8] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 128 - 253 @@ -501,37 +500,34 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 labels and compression labels. Compression labels are pointers to data labels elsewhere within an RR or DNS message and are intended to shorten the wire encoding of NAMEs. The two existing data label - types are frequently referred to as ASCII and Binary. ASCII labels - can, in fact, include any octet value including zero octets but most - current uses involve only [US-ASCII] For retrieval ASCII labels are - defined to treat upper and lower case letters the same. Binary - labels are bit sequences [RFC 2673]. + types are sometimes referred to as Text and Binary. Text labels can, + in fact, include any octet value including zero octets but most + current uses involve only [US-ASCII]. For retrieval, Text labels are + defined to treat ASCII upper and lower case letter codes as matching. + Binary labels are bit sequences [RFC 2673]. IANA considerations for label types are given in [RFC 2671]. - NAMEs are local to a CLASS. The Hesiod [Dyer 87] and Chaos [Moon 81] - CLASSes are essentially for local use. The IN or Internet CLASS is - thus the only DNS CLASS in global use on the Internet at this time. + NAMEs are local to a CLASS. The Hesiod [Dyer 1987] and Chaos [Moon + 1981] CLASSes are essentially for local use. The IN or Internet + CLASS is thus the only DNS CLASS in global use on the Internet at + this time. A somewhat dated description of name allocation in the IN Class is given in [RFC 1591]. Some information on reserved top level domain - names is in Best Current Practice 32 [RFC 2606]. D. Eastlake 3rd, E. Brunner, B. Manning [Page 9] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 -4. Designated Expert - - To provide additional support to IANA in the DNS area, the IESG MAY - appoint a designed expert. + names is in Best Current Practice 32 [RFC 2606]. -5. Security Considerations +4. Security Considerations This document addresses IANA considerations in the allocation of general DNS parameters, not security. See [RFC 2535] for secure DNS @@ -539,12 +535,58 @@ INTERNET-DRAFT DNS IANA Considerations February 2000 + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +D. Eastlake 3rd, E. Brunner, B. Manning [Page 10] + + +INTERNET-DRAFT DNS IANA Considerations June 2000 + + References - [Dyer 87] - Dyer, S., and F. Hsu, "Hesiod", Project Athena Technical - Plan - Name Service, April 1987, + [Dyer 1987] - Dyer, S., and F. Hsu, "Hesiod", Project Athena + Technical Plan - Name Service, April 1987, - [Moon 81] - D. Moon, "Chaosnet", A.I. Memo 628, Massachusetts + [Moon 1981] - D. Moon, "Chaosnet", A.I. Memo 628, Massachusetts Institute of Technology Artificial Intelligence Laboratory, June 1981. @@ -575,106 +617,63 @@ References [RFC 2606] - D. Eastlake, A. Panitz, "Reserved Top Level DNS Names", June 1999. - -D. Eastlake 3rd, E. Brunner, B. Manning [Page 10] - - -INTERNET-DRAFT DNS IANA Considerations February 2000 - - [RFC 2671] - P. Vixie, "Extension mechanisms for DNS (EDNS0)", August 1999. - [RFC 2672] - M. Crawford, " Non-Terminal DNS Name Redirection", - August 1999. + [RFC 2672] - M. Crawford, "Non-Terminal DNS Name Redirection", August + 1999. [RFC 2673] - M. Crawford, "Binary Labels in the Domain Name System", August 1999. - [RFC XXX3] - P. Vixie, O. Gudmundsson, D. Eastlake, B. Wellington, - "Secret Key Transaction Signatures for DNS (TSIG)", xxx 2000 (draft- - ietf-dnsind-tsig-*.txt). - - [US-ASCII] - ANSI, "USA Standard Code for Information - Interchange", X3.4, American National Standards Institute: New York, - 1968. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + [RFC 2845] - P. Vixie, O. Gudmundsson, D. Eastlake, B. Wellington, + "Secret Key Transaction Authentication for DNS (TSIG)", May 2000. + [draft-ietf-dnsext-tkey-*.txt] - D. Eastlake, "Secret Key + Establishment for DNS (TKEY RR)", xxx 2000. D. Eastlake 3rd, E. Brunner, B. Manning [Page 11] -INTERNET-DRAFT DNS IANA Considerations February 2000 +INTERNET-DRAFT DNS IANA Considerations June 2000 + + + [US-ASCII] - ANSI, "USA Standard Code for Information Interchange", + X3.4, American National Standards Institute: New York, 1968. + + + + + + + + + + + + + + + + + + + + + + + + + + -Authors Addresses - - Donald E. Eastlake 3rd - Motorola - 65 Shindegan Hill Road - Carmel, NY 10512 USA - - Telephone: +1-914-276-2668 (h) - +1-508-261-5434 (w) - email: dee3@torque.pothole.com - - - Eric Brunner - 1415 Forest Avenue - Portland, ME 04103 USA - - Telephone: +1 207-797-0525 - email: brunner@world.std.com - - - Bill Manning - USC/ISI - 4676 Admiralty Way, #1001 - Marina del Rey, CA 90292 USA - - Telephone: +1 310 822 1511 - email: bmanning@isi.edu -Expiration and File Name - This draft expires August 2000. - Its file name is draft-ietf-dnsext-iana-dns-00.txt. @@ -694,3 +693,61 @@ Expiration and File Name D. Eastlake 3rd, E. Brunner, B. Manning [Page 12] + +INTERNET-DRAFT DNS IANA Considerations June 2000 + + +Authors Addresses + + Donald E. Eastlake 3rd + Motorola + 140 Forest Avenue + Hudson, MA 01749 USA + + Telephone: +1-978-562-2827 (h) + +1-508-261-5434 (w) + fax: +1-508-261-4447 (w) + email: Donald.Eastlake@motorola.com + + + Eric Brunner + Engage Technologies + 100 Brickstone Square, 2nd Floor + Andover, MA 01810 + + Telephone: +1-978-684-7796 (voice) + +1-978-684-3636 (fax) + email: brunner@engage.com + + + Bill Manning + USC/ISI + 4676 Admiralty Way, #1001 + Marina del Rey, CA 90292 USA + + Telephone: +1 310 822 1511 + email: bmanning@isi.edu + + + +Expiration and File Name + + This draft expires December 2000. + + Its file name is draft-ietf-dnsext-iana-dns-02.txt. + + + + + + + + + + + + + + +D. Eastlake 3rd, E. Brunner, B. Manning [Page 13] + diff --git a/doc/draft/draft-ietf-dnsext-message-size-00.txt b/doc/draft/draft-ietf-dnsext-message-size-00.txt new file mode 100644 index 0000000000..2a276d010d --- /dev/null +++ b/doc/draft/draft-ietf-dnsext-message-size-00.txt @@ -0,0 +1,282 @@ + + + + + + +DNSEXT Working Group Olafur Gudmundsson (NAI Labs) +INTERNET-DRAFT June 2000 + + + +Updates: RFC 2535 + + + + DNSSEC and IPv6 A6 aware server/resolver message size requirements + + +Status of this Memo + + This document is an Internet-Draft and is in full conformance with + all provisions of Section 10 of RFC2026. + + Internet-Drafts are working documents of the Internet Engineering + Task Force (IETF), its areas, and its working groups. Note that + other groups may also distribute working documents as Internet- + Drafts. + + Internet-Drafts are draft documents valid for a maximum of six months + and may be updated, replaced, or obsoleted by other documents at any + time. It is inappropriate to use Internet-Drafts as reference + material or to cite them other than as ``work in progress.'' + + The list of current Internet-Drafts can be accessed at + http://www.ietf.org/ietf/1id-abstracts.txt + + The list of Internet-Draft Shadow Directories can be accessed at + http://www.ietf.org/shadow.html + + Comments should be sent to the authors or the DNSEXT WG mailing list + namedroppers@ops.ietf.org + + This draft expires on December 29, 2000. + + Copyright Notice + + Copyright (C) The Internet Society (2000). All rights reserved. + + + + + + + + + + +Expires December 2000 [Page 1] + +INTERNET-DRAFT DNSSEC and IPng message size requirement June 2000 + + +Abstract + + This document mandates support for EDNS0 in DNS entities claiming to + support DNS Security Extensions and A6 records. This requirement is + necessary because these new features increase the size of DNS + messages. If EDNS0 is not supported fallback to TCP will happen, + having a detrimental impact on query latency and DNS server load. + + + + +1 - Introduction + + Familiarity with the DNS [RFC1034, RFC1035], DNS Security Extensions + [RFC2535], EDNS0[RFC2671] and A6 [RFCA6] is helpful. + + RFC 1035[RFC1035] Section 2.3.4 requires that DNS messages over UDP + have a data payload of 512 octets or less. Most DNS software today + will not accept larger size UDP datagrams. Thus, any answer that + requires more than 512 octets will result in a partial and probably + useless reply with the Truncation Bit set; in most cases the + requester will then retry using TCP. Some DNS servers send back an + answer truncating the message at the last RR boundary before + truncation, other servers truncate at the previous set, some send + back empty answer with TC bit set. + + Compared to UDP, TCP is an expensive protocol to use for a simple + transaction like DNS: a TCP connection requires 5 packets for setup + and teardown, excluding data packets, thus requiring at least 3 + round trips on top of the one for the original UDP query. The DNS + server also needs to keep a state of the connection during this + transaction. As many DNS servers answer thousands of queries per + second, requiring them to use TCP will cause significant overhead and + delays. + + DNSSEC[RFC2535] secures DNS by adding a Public Key signature on each + RR set. These signatures range in size from about 80 octets to 800 + octets most are going to be in the range of 80..200 octets. The + addition of these signatures on each or most RR sets in an answer + will significantly increase the size of DNS answers from secure + zones. + + + TSIG[RFC2845] allows for the light weight authentication of DNS + messages, but increases the size of the messages by at least 70 + octets. DNSSEC allows for computationally expensive message + authentication with a standard public key signature. As only one TSIG + or SIG(0) can be attached to each DNS answer the size increase of + + + +Expires December 2000 [Page 2] + +INTERNET-DRAFT DNSSEC and IPng message size requirement June 2000 + + + message authentication is not significant. + + + IPv6 addresses[A6] are 128 bits and are represented in the DNS by + multiple A6 records, each consisting of a domain name and a bit + field. The domain name refers to an address prefix that may require + additional A6 RRs to be included in the answer. Answers where + queried name has multiple A6 addresses may overflow a 512-octet UDP + packet size. + + The current number of root servers is limited to 13 as that is the + maximum number of name servers and their address records that fit in + one 512-octet DNS message. If root servers start advertising A6 or + KEY records then the root zone answer for NS records will not fit in + an single 512-octet DNS message. Resulting in a large number of TCP + connections to the root servers. + + Given all these factors, it is essential that any implementations + that supports DNSSEC and or A6 be able to use larger DNS messages + than 512 octets. + + EDNS0[RFC2671] allows clients to declare the maximum size of UDP + message they are willing to handle. Thus, if the expected answer is + between 512 octets and the maximum size that the client can accept, + the additional overhead of a TCP connection can be avoided. + + +1.2 - Requirements + + The key words "MUST", "REQUIRED", "SHOULD", "RECOMMENDED", and "MAY" + in this document are to be interpreted as described in RFC 2119. + + +2 - Protocol changes: + + This document updates [RFC2535] and [A6]. + + All RFC2535-compliant servers and resolvers MUST support EDNS0 and + advertise message size of at least 1280 octets. + + All [A6] compliant servers and resolver MUST support EDNS0 and + advertise message size of at least 1280 octets. + + + + + + + + + +Expires December 2000 [Page 3] + +INTERNET-DRAFT DNSSEC and IPng message size requirement June 2000 + + +3 Acknowledgments + + Harald Alvestrand, Rob Austein, Randy Bush, David Conrad, Andreas + Gustafsson, Bob Halley and Edward Lewis where instrumental in + motivating and shaping this document. + +4 - Security Considerations: + + There are no additional security considerations other than those in + RFC2671. + + +5 - IANA Considerations: + + None + + +References: + + +[RFC1035] P. Mockapetris, ``Domain Names - Implementation and + Specification'', STD 13, RFC 1035, November 1987. + + +[RFC2535] D. Eastlake, ``Domain Name System Security Extensions'', RFC + 2535, March 1999. + + +[RFC2671] P. Vixie, ``Extension Mechanisms for DNS (EDNS0)'', RFC + 2671, August 1999. + + +[RFC2845] P. Vixie, O. Gudmundsson, D. Eastlake, B. Wellington, + ``Secret Key Transaction Authentication for DNS (TSIG)'', RFC + 2845, May 2000. + + +[A6] M. Crawford, C. Huitema, S. Thompson, ``DNS Extensions to + Support IPv6 Address Aggregation and Renumbering'', RFCxxx, + Sometime 2000. + + + + + + + + + + + +Expires December 2000 [Page 4] + +INTERNET-DRAFT DNSSEC and IPng message size requirement June 2000 + + +Author Address + + + Olafur Gudmundsson + NAI Labs + Network Associates + 3060 Washington Road (Rt. 97) + Glenwood, MD 21738 + USA + +1 443 259 2389 + + + +Full Copyright Statement + + Copyright (C) The Internet Society (2000). All Rights Reserved. + + This document and translations of it may be copied and furnished to + others, and derivative works that comment on or otherwise explain it + or assist in its implementation may be prepared, copied, published + and distributed, in whole or in part, without restriction of any + kind, provided that the above copyright notice and this paragraph are + included on all such copies and derivative works. However, this + document itself may not be modified in any way, such as by removing + the copyright notice or references to the Internet Society or other + Internet organizations, except as needed for the purpose of + developing Internet standards in which case the procedures for + copyrights defined in the Internet Standards process must be + followed, or as required to translate it into languages other than + English. + + The limited permissions granted above are perpetual and will not be + revoked by the Internet Society or its successors or assigns. + + This document and the information contained herein is provided on an + "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING + TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING + BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION + HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF + MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE." + + + + + + + + + + + +Expires December 2000 [Page 5]