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INTERNET-DRAFT Edward Lewis
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draft-ietf-dnsext-axfr-clarify-09.txt NeuStar, Inc.
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DNSEXT WG July 2008
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Updates: 1034, 1035 (if approved) Intended status: Standards Track
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DNS Extensions Working Group Edward Lewis
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INTERNET-DRAFT NeuStar, Inc.
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Expires: July 1, 2009 January 2009
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Updates: 1034, 1035 (if approved)
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Intended status: Standards Track
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DNS Zone Transfer Protocol (AXFR)
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draft-ietf-dnsext-axfr-clarify-10.txt
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DNS Zone Transfer Protocol (AXFR)
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Status of this Memo
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||||
By submitting this Internet-Draft, each author represents that any
|
||||
applicable patent or other IPR claims of which he or she is aware
|
||||
have been or will be disclosed, and any of which he or she becomes
|
||||
aware will be disclosed, in accordance with Section 6 of BCP 79.
|
||||
This Internet-Draft is submitted to IETF in full conformance with the
|
||||
provisions of BCP 78 and BCP 79.
|
||||
|
||||
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 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."
|
||||
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 current Internet-Drafts can be accessed at
|
||||
http://www.ietf.org/1id-abstracts.html
|
||||
|
||||
The list of Internet-Draft Shadow Directories can be accessed at
|
||||
http://www.ietf.org/shadow.html.
|
||||
|
||||
This Internet-Draft will expire on December 31, 2008.
|
||||
The list of Internet-Draft Shadow Directories can be accessed at
|
||||
http://www.ietf.org/shadow.html
|
||||
|
||||
Copyright Notice
|
||||
|
||||
Copyright (C) The IETF Trust (2008).
|
||||
Copyright (c) 2008 IETF Trust and the persons identified as the
|
||||
document authors. All rights reserved.
|
||||
|
||||
This document is subject to BCP 78 and the IETF Trust's Legal
|
||||
Provisions Relating to IETF Documents
|
||||
(http://trustee.ietf.org/license-info) in effect on the date of
|
||||
publication of this document. Please review these documents
|
||||
carefully, as they describe your rights and restrictions with
|
||||
respect to this document.
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|
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Abstract
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@ -139,7 +146,7 @@ documents.
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The original "specification" of the AXFR sub-protocol is scattered
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through RFC 1034 and RFC 1035. Section 2.2 of RFC 1035 on page 5
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depicts the scenario for which AXFR has been designed. Section 4.3.5
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of RFC 1034 describes the zone synchronisation strategies in general
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of RFC 1034 describes the zone synchronization strategies in general
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and rules for the invocation of a full zone transfer via AXFR; the
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fifth paragraph of that section contains a very short sketch of the
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AXFR protocol. Section 3.2.3 of RFC 1035 has assigned the code point
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@ -162,13 +169,12 @@ define AXFR as it exists, or is supposed to exist, currently.
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2 AXFR Messages
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An AXFR message exchange (or session) consists of an AXFR query message
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and a set of AXFR response messages. In this document, AXFR client is
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An AXFR session consists of an exchange of a AXFR query message and a
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set of AXFR response messages. In this document, the AXFR client is
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the sender of the AXFR query and the AXFR server is the responder.
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(Use of terms such as master, slave, primary, secondary are not
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important to defining the AXFR exchange.) The reason for the imbalance
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in number of messages derives from large zones whose contents cannot be
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fit into the limited permissible size of a DNS message.
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important to defining AXFR.) The use of the word "session" without
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qualification refers to an AXFR session.
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An important aspect to keep in mind is that the definition of AXFR is
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restricted to TCP [RFC0793]. The design of the AXFR process has
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|
|
@ -177,7 +183,7 @@ certain inherent features that are not easily ported to UDP [RFC0768].
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The basic format of an AXFR message is the DNS message as defined in
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RFC 1035, Section 4 ("MESSAGES") [RFC1035], updated by the following:
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- "A Mechanism for Prompt Notification of Zone Changes (...)" [RFC1996]
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- "Domain Name System (DNS) IANA Considerations" [RFC2929]
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- "Domain Name System (DNS) IANA Considerations" [RFC5395]
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- "Dynamic Updates in the Domain Name System (DNS UPDATE)" [RFC2136]
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- "Extension Mechanisms for DNS (EDNS0)" [RFC2671]
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- "Secret Key Transaction Authentication for DNS (TSIG)" [RFC2845]
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@ -188,8 +194,11 @@ RFC 1035, Section 4 ("MESSAGES") [RFC1035], updated by the following:
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- "HMAC SHA TSIG Algorithm Identifiers" [RFC4635]
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|
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The upper limit on the permissible size of a DNS message over TCP is
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defined in RFC 1035, section 4.2.2. Unlike DNS messages over UDP,
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this limit is not changed by EDNS0.
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only restricted by the TCP framing defined in RFC 1035, section 4.2.2
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which specifies a two-octet message length field, understood to be
|
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unsigned, and thus causing a limit of 65535 octets. Unlike DNS
|
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messages over UDP, this limit is not changed by EDNS0.
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|
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Field names used in this document will correspond to the names as they
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appear in the IANA registry for DNS Header Flags [DNSFLGS].
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|
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@ -294,7 +303,7 @@ additional section might change over time. If either a change to an
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existing resource record (like the OPT RR for EDNS0) is made or
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a new additional section record is created, the new definitions ought
|
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to include a discussion on the impact upon AXFR. Although this is not
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predictale, future additional section residing records may have an
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predictable, future additional section residing records may have an
|
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effect that is orthogonal to AXFR, so can ride through the session as
|
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opaque data. In this case, a "wise" implementation ought to be able
|
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to pass these records through without disruption.
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|
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@ -323,7 +332,8 @@ necessary.
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An AXFR client might receive a number of AXFR response messages
|
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free of an error condition before the message indicating an error
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is received. But once an error is reported, the AXFR client can
|
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assume that the error reporting message is the last.
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assume that the error reporting message is the last message sent by
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the AXFR server in the current AXFR session.
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2.2.1 "0 Message" Response
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|
|
@ -333,33 +343,16 @@ is unhealthy for there to be 0 responses in a protocol that is designed
|
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around a query - response paradigm over an unreliable transport. The
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lack of a response could be a sign of underlying network problems and
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cause the protocol state machine to react accordingly. However, AXFR
|
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uses TCP and not UDP, eliminating undetected network errors.
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uses TCP and not UDP, eliminating undetectable network errors.
|
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|
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A "0 message response" is reserved for situations in which the server
|
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has a reason to suspect that the query is sent for the purpose of
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abuse. Due to the use of this being so controversial, a "0 message
|
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response" is not being defined as a legitimate part of the protocol
|
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but the use of it is being acknowledge as a warning to AXFR client
|
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but the use of it is being acknowledged as a warning to AXFR client
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implementations. Any earnest query has the expectation of some
|
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response but may not get one.
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|
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If an AXFR client sends a query on a TCP connection and the connection
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is closed at any point, the AXFR client MUST consider the session
|
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terminated. The message ID MAY be used again on a new connection,
|
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even if the question and AXFR server are the same. Facing a dropped
|
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connection a client SHOULD try to make some determination whether the
|
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connection closure was the result of network activity or a decision
|
||||
by the AXFR server. This determination is not an exact science. It
|
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is up to the AXFR client implementor to react, but the reaction
|
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SHOULD NOT be an endless cycle of retires nor an increasing (in
|
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frequency) retry rate.
|
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|
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An AXFR server implementor SHOULD take into consideration what this
|
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dilemma described above when a connection is closed with an outstanding
|
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query in the pipeline. For this reason, a server ought to reserve
|
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this course of action for situations in which it believes beyond a
|
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doubt that the AXFR client is attemping abusive behavior.
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|
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2.2.2 Header Values
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|
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ID See note 2.2.2.a
|
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|
|
@ -446,11 +439,14 @@ resource records appearing in the additional section. See Section
|
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2.2.3 Query Section
|
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|
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In the first response message, this section MUST be copied from the
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query. In subsequent messages this section MAY be copied from the
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query, MAY be empty. The content of this section MAY be used to
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query. In subsequent messages, this section MAY be copied from the
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query or it MAY be empty. The content of this section MAY be used to
|
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determine the context of the message, that is, the name of the zone
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being transferred.
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>| [...]. In subsequent messages, this section MAY be copied from the
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>| query, or it MAY be empty. [...]
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2.2.4 Answer Section
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MUST be populated with the zone contents. See later section on
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@ -460,7 +456,7 @@ encoding zone contents.
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MUST be empty.
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2.2.5 Additional Section
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2.2.6 Additional Section
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|
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The contents of this section MUST follow the guidelines for EDNS0,
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TSIG, SIG(0), or what ever other future record is possible here. The
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|
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@ -469,10 +465,29 @@ contents of section 2.1.5 apply here as well.
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Note that TSIG and SIG(0), if in use, will treat each individual
|
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AXFR response message within a session as a unit of data. That is,
|
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each message will have a TSIG or SIG(0) (if in use) and the
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crytpographic check will cover just that message. The same rule
|
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cryptographic check will cover just that message. The same rule
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will apply to future alternatives and documents covering them ought
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to consider the impact on AXFR response messages.
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2.3 TCP Connection Aborts
|
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|
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If an AXFR client sends a query on a TCP connection and the connection
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is closed at any point, the AXFR client MUST consider the AXFR session
|
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terminated. The message ID MAY be used again on a new connection,
|
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even if the question and AXFR server are the same. Facing a dropped
|
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connection a client SHOULD try to make some determination whether the
|
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connection closure was the result of network activity or a decision
|
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by the AXFR server. This determination is not an exact science. It
|
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is up to the AXFR client implementor to react, but the reaction
|
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SHOULD NOT be an endless cycle of retries nor an increasing (in
|
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frequency) retry rate.
|
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|
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An AXFR server implementor SHOULD take into consideration the dilemma
|
||||
described above when a connection is closed with an outstanding query
|
||||
in the pipeline. For this reason, a server ought to reserve this
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course of action for situations in which it believes beyond a doubt
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that the AXFR client is attempting abusive behavior.
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3 Zone Contents
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The objective of the AXFR session is to request and transfer the
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@ -497,7 +512,11 @@ records as will fit within a DNS message.
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Zones for which it is impractical to list the entire zones for a serial
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number (because changes happen too quickly) are not suitable for AXFR
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retrieval.
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retrieval. A typical (but not limiting) description of such a zone
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is a zone consisting of responses generated via other database lookups
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and/or computed based upon ever changing data. In essence, if the
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zone changes (on average) more frequently than and AXFR session can be
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finished, the zone is not a good candidate for AXFR.
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3.2 Delegation Records
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|
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@ -511,11 +530,12 @@ included in a zone transfer.
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The phrase "that describe cuts" is a reference to the NS set and
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applicable glue records. It does not mean that the cut points and the
|
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apex resource records are identical. For example, the SOA resource
|
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record is only found at the apex, as well as a slew of DNSSEC resource
|
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records. There are also some DNSSEC resource record sets that are
|
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explicitly different between the cut point and the apex. The
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discussion here is restricted to just the NS resource record set and
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glue as these "describe cuts."
|
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record is only found at the apex, as well as DNSSEC resource records.
|
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The is even a DNSSEC resource record found only at the zone cut and not
|
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at the corresponding apex. There are also some DNSSEC resource record
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sets that are explicitly different between the cut point and the apex.
|
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The discussion here is restricted to just the NS resource record set
|
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and glue as these "describe cuts."
|
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|
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The issue is that in operations there are times when the NS resource
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records for a zone might be different at a cut point in the parent and
|
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|
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@ -525,7 +545,7 @@ protocol is robust enough to overcome inconsistencies up to (but not
|
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including) there being no parent indicated NS resource record
|
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referencing a server that is able to serve the child zone. This
|
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robustness is one quality that has fueled the success of the DNS.
|
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Still, the inconsistency is a error state and steps need to be taken
|
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Still, the inconsistency is an error state and steps need to be taken
|
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to make it apparent (if it is unplanned) and to make it clear once
|
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the inconsistency has been removed.
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|
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@ -538,7 +558,7 @@ the cut point.
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The question that arises is, when facing a situation in which a cut
|
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point's NS resource records do not match the authoritative set, whether
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an AXFR server responds with the NS resource record set that is in the
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zone or is at the authoritative location.
|
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zone being transferred or is at the authoritative location.
|
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|
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The AXFR response MUST contain the cut point NS resource record set
|
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registered with the zone whether it agrees with the authoritative set
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|
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@ -567,7 +587,7 @@ in a registration database.
|
|||
|
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4) Beginning with an error state of two servers for a zone having
|
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inconsistent zone contents for a given zone serial number, if a client
|
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requests and recieves an IXFR transfer from one server followed by
|
||||
requests and receives an IXFR transfer from one server followed by
|
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another IXFR transfer from the other server, the client can encounter
|
||||
an IXFR protocol error state where an attempt is made to incrementally
|
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add a record that already exists or to delete a record that does not
|
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|
|
@ -578,7 +598,7 @@ it relates. A nudge for updated text on this.)
|
|||
|
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3.3 Glue Records
|
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|
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As quoted in the previous section, RFC 1034, section 4.2.1, provides
|
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As quoted in the previous section, section 4.2.1 of RFC 1034 provides
|
||||
guidance and rationale for the inclusion of glue records as part of
|
||||
an AXFR transfer. And, as also argued in the previous section of this
|
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document, even when there is an inconsistency between the address in a
|
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|
|
@ -586,7 +606,7 @@ glue record and the authoritative copy of the name server's address,
|
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the glue resource record that is registered as part of the zone for
|
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that serial number is to be included.
|
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|
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This applies for glue records for any address family.
|
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This applies to glue records for any address family [RFC1700].
|
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|
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The AXFR response MUST contain the appropriate glue records as
|
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registered with the zone. The interpretation of "registered with"
|
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|
|
@ -615,12 +635,12 @@ Compression."
|
|||
|
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3.5 Occluded Names
|
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|
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Dynamic Update [RFC2136] (and including DNAME [2672]) operations can
|
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Dynamic Update [RFC2136] (and including DNAME [RFC2672]) operations can
|
||||
have a side effect of occluding names in a zone. The addition of a
|
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delegation point via dynamic update will render all subordinate domain
|
||||
names to be in a limbo, still part of the zone but not available for to
|
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the look up process. The addition of a DNAME resource record set has
|
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the same impact. The subordinate names are said to be "occluded."
|
||||
names to be in a limbo, still part of the zone but not available
|
||||
to the lookup process. The addition of a DNAME resource record has the
|
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same impact. The subordinate names are said to be "occluded."
|
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|
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Occluded names MUST be included in AXFR responses. An AXFR client MUST
|
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be able to identify and handle occluded names. The rationale for this
|
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|
|
@ -631,20 +651,20 @@ was in error and is to be undone.
|
|||
|
||||
AXFR sessions are currently restricted to TCP by section 4.3.5 of RFC
|
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1034 that states: "Because accuracy is essential, TCP or some other
|
||||
reliable protocol must be used for AXFR requests." The most common
|
||||
scenario is for an AXFR client to open a TCP connection to the AXFR
|
||||
server, send an AXFR query, receive the AXFR response, and then
|
||||
close the connection. There are variations on this, such as a query
|
||||
for the zone's SOA resource record first, and so on.
|
||||
reliable protocol must be used for AXFR requests." The restriction to
|
||||
TCP is also mentioned in section 6.1.3.2. of "Requirements for Internet
|
||||
Hosts - Application and Support" [RFC1123].
|
||||
|
||||
Two issues have emerged since the original specification of AXFR.
|
||||
One is that lack of specificity has yielded some implementations
|
||||
that assume the TCP connection is dedicated to the single AXFR
|
||||
session, which has led to implementation choices that prevent either
|
||||
multiple concurrent zone transfers or the use of the open connection
|
||||
for other queries. The other issue is the prospect of using UDP as a
|
||||
transport has come to look promising because of trends in the past
|
||||
two decades.
|
||||
The most common scenario is for an AXFR client to open a TCP connection
|
||||
to the AXFR server, send an AXFR query, receive the AXFR response, and
|
||||
then close the connection. There are variations on this, such as a
|
||||
query for the zone's SOA resource record first, and so on. Note that
|
||||
this is documented as a most common scenario.
|
||||
|
||||
The assumption that a TCP connection is dedicated to the single AXFR
|
||||
session is incorrect, this as has led to implementation choices that
|
||||
prevent either multiple concurrent zone transfers or the use of the
|
||||
open connection for other queries.
|
||||
|
||||
Being able to have multiple concurrent zone transfers is considered
|
||||
desirable by operators who have sets of name servers that are
|
||||
|
|
@ -690,10 +710,11 @@ reason. An AXFR client SHOULD close the connection when there is
|
|||
no apparent need to use the connection for some time period. The
|
||||
AXFR server ought not have to maintain idle connections, the burden
|
||||
of connection closure ought to be on the client. Apparent need for
|
||||
the connection is a judgement for the AXFR client and the DNS
|
||||
client. If the connection is used for multiple sessions, or it is
|
||||
known sessions will be coming or is there is other query/response
|
||||
traffic on the open connection, that is "apparent need."
|
||||
the connection is a judgment for the AXFR client and the DNS
|
||||
client. If the connection is used for multiple sessions, or if it is
|
||||
known sessions will be coming or if there is other query/response
|
||||
traffic anticipated or currently on the open connection, then there
|
||||
is "apparent need."
|
||||
|
||||
An AXFR client MAY cancel delivery of a zone only by closing the
|
||||
connection. However, this action will also cancel all other outstanding
|
||||
|
|
@ -719,7 +740,7 @@ opening a new connection. (Non-AXFR session traffic can also use an
|
|||
open connection.) If in doing so the AXFR client realizes that
|
||||
the responses cannot be properly differentiated (lack of matching
|
||||
query IDs for example) or the connection is terminated for a remote
|
||||
reason, then the AXFR client SHOULD not attempt to reuse an open
|
||||
reason, then the AXFR client SHOULD NOT attempt to reuse an open
|
||||
connection with the specific AXFR server until the AXFR server is
|
||||
updated (which is of course, not an event captured in the DNS
|
||||
protocol).
|
||||
|
|
@ -758,8 +779,7 @@ serving AXFR. All reasons are arguable, but the fact remains that
|
|||
there is a requirement to provide mechanisms to restrict AXFR.
|
||||
|
||||
A DNS implementation SHOULD provide means to restrict AXFR sessions to
|
||||
specific clients. By default, a DNS implementation SHOULD only allow
|
||||
the designated authoritative servers to have access to the zone.
|
||||
specific clients.
|
||||
|
||||
An implementation SHOULD allow access to be granted to Internet
|
||||
Protocol addresses and ranges, regardless of whether a source address
|
||||
|
|
@ -777,10 +797,32 @@ all AXFR requests. I.e., an operator ought to be able to allow any
|
|||
AXFR query to be granted.
|
||||
|
||||
A general purpose implementation SHOULD NOT have a default policy
|
||||
for AXFR requests to be "open to all."
|
||||
for AXFR requests to be "open to all." For example, a default could
|
||||
be to restrict transfers to loopback address(es) and such.
|
||||
|
||||
6 Zone Integrity
|
||||
|
||||
An AXFR client MUST ensure that only a successfully transferred
|
||||
copy of the zone data can be used to serve this zone. Previous
|
||||
description and implementation practice have introduced a two-stage
|
||||
model of the whole zone synchronization procedure: Upon a trigger
|
||||
event (e.g., polling of SOA resource record detects change in the
|
||||
SOA serial number, or via DNS NOTIFY [RFC1996]), the AXFR session
|
||||
is initiated, whereby the zone data are saved in a zone file or
|
||||
data base (this latter step is necessary anyway to ensure proper
|
||||
restart of the server); upon successful completion of the AXFR
|
||||
operation and some sanity checks, this data set is 'loaded' and
|
||||
made available for serving the zone in an atomic operation, and
|
||||
flagged 'valid' for use during the next restart of the DNS server;
|
||||
if any error is detected, this data set MUST be deleted, and the
|
||||
AXFR client MUST continue to serve the previous version of the zone,
|
||||
if it did before. The externally visible behavior of an AXFR client
|
||||
implementation MUST be equivalent to that of this two-stage model.
|
||||
|
||||
If a server rejects data contained in an AXFR session, the server
|
||||
SHOULD remember the serial number and not attempt to retrieve the
|
||||
same zone version again.
|
||||
|
||||
Ensuring that an AXFR client does not accept a forged copy of a zone is
|
||||
important to the security of a zone. If a zone operator has the
|
||||
opportunity, protection can be afforded via dedicated links, physical
|
||||
|
|
@ -794,7 +836,34 @@ Authentication for DNS" [RFC2845] and/or "DNS Request and Transaction
|
|||
Signatures ( SIG(0)s )" [RFC2931] to allow AXFR clients to verify the
|
||||
contents. These techniques MAY also be used for authorization.
|
||||
|
||||
7 Backwards Compatibility
|
||||
7 Zone Expiry Timer
|
||||
|
||||
Section 4.3.5 of RFC 1034 contains the following paragraph:
|
||||
|
||||
"The periodic polling of the secondary servers is controlled by
|
||||
parameters in the SOA RR for the zone, which set the minimum acceptable
|
||||
polling intervals. The parameters are called REFRESH, RETRY, and
|
||||
EXPIRE. Whenever a new zone is loaded in a secondary, the secondary
|
||||
waits REFRESH seconds before checking with the primary for a new serial.
|
||||
If this check cannot be completed, new checks are started every RETRY
|
||||
seconds. The check is a simple query to the primary for the SOA RR of
|
||||
the zone. If the serial field in the secondary's zone copy is equal to
|
||||
the serial returned by the primary, then no changes have occurred, and
|
||||
the REFRESH interval wait is restarted. If the secondary finds it
|
||||
impossible to perform a serial check for the EXPIRE interval, it must
|
||||
assume that its copy of the zone is obsolete an discard it."
|
||||
|
||||
Perhaps what is not clear in the paragraph regarding the EXPIRE
|
||||
interval timer is that it is only reset to the EXPIRE parameter when
|
||||
a new zone is loaded. A new zone means a zone with a higher serial
|
||||
number than the most recently loaded zone. The EXPIRE interval timer
|
||||
is not reset automatically as a result of a zone transfer as a zone
|
||||
could be (mistakenly) transferred with the same or lower serial number.
|
||||
|
||||
I.e., successively transferring a zone from server to server does not
|
||||
permit the zone to avoid expiration.
|
||||
|
||||
8 Backwards Compatibility
|
||||
|
||||
Describing backwards compatibility is difficult because of the lack of
|
||||
specifics in the original definition. In this section some hints at
|
||||
|
|
@ -813,7 +882,7 @@ implementation SHOULD, in it's documentation, encourage operators to
|
|||
periodically review AXFR clients and servers it has made notes about as
|
||||
old software periodically gets updated.
|
||||
|
||||
7.1 Server
|
||||
8.1 Server
|
||||
|
||||
An AXFR server has the luxury of being able to react to an AXFR
|
||||
client's abilities with the exception of knowing if the client can
|
||||
|
|
@ -825,7 +894,7 @@ An implementation of an AXFR server SHOULD permit configuring, on a per
|
|||
AXFR client basis, a need to revert to single resource record per
|
||||
message. The default SHOULD be to use multiple records per message.
|
||||
|
||||
7.2 Client
|
||||
8.2 Client
|
||||
|
||||
An AXFR client has the opportunity to try extensions when querying
|
||||
an AXFR server.
|
||||
|
|
@ -836,23 +905,23 @@ and SHOULD take into consideration whether the AXFR server intends to
|
|||
close the connection immediately upon completion of the original
|
||||
(connection-causing) zone transfer.
|
||||
|
||||
8 Security Considerations
|
||||
9 Security Considerations
|
||||
|
||||
Concerns regarding authorization, traffic flooding, and message
|
||||
integrity are mentioned in "Authorization" (section 5), "TCP" (section
|
||||
4.2) and Zone Integrity (section 6).
|
||||
4.2) and "Zone Integrity" (section 6).
|
||||
|
||||
9 IANA Considerations
|
||||
10 IANA Considerations
|
||||
|
||||
No new registries or new registrations are included in this document.
|
||||
|
||||
10 Internationalization Considerations
|
||||
11 Internationalization Considerations
|
||||
|
||||
It is assumed that supporting of international domain names has been
|
||||
solved via "Internationalizing Domain Names in Applications (IDNA)"
|
||||
[RFC3490].
|
||||
|
||||
11 Acknowledgements
|
||||
12 Acknowledgements
|
||||
|
||||
Earlier editions of this document have been edited by Andreas
|
||||
Gustafsson. In his latest version, this acknowledgement appeared.
|
||||
|
|
@ -868,15 +937,15 @@ Alfred Hoenes, Mark Andrews, Paul Vixie, Wouter Wijngaards, Iain
|
|||
Calder, Tony Finch, Ian Jackson, Andreas Gustafsson, Brian Wellington,
|
||||
...
|
||||
|
||||
12 References
|
||||
13 References
|
||||
|
||||
All references prefixed by "RFC" can be obtained from the RFC Editor,
|
||||
All references prefixed by "RFC" can be obtained from the RFC Editor
|
||||
web site at the URLs: http://rfc-editor.org/rfc.html
|
||||
or http://rfc-editor.org/rfcsearch.html ;
|
||||
information regarding this organization can be found at the following
|
||||
URL:
|
||||
http://rfc-editor.org/
|
||||
Additionally, these documents can be obtained via the IETF web site.
|
||||
URL: http://rfc-editor.org/
|
||||
|
||||
12.1 Normative
|
||||
13.1 Normative
|
||||
|
||||
[RFC0793] Postel, J., "Transmission Control Protocol", STD 7, RFC 793,
|
||||
September 1981.
|
||||
|
|
@ -886,6 +955,8 @@ Additionally, these documents can be obtained via the IETF web site.
|
|||
STD 13, RFC 1034, November 1987.
|
||||
[RFC1035] Mockapetris, P., "Domain names - implementation and
|
||||
specification", STD 13, RFC 1035, November 1987.
|
||||
[RFC1123] Braden, R., "Requirements for Internet Hosts - Application
|
||||
and Support", STD 3, RFC 1123, October 1989.
|
||||
[RFC1995] Ohta, M., "Incremental Zone Transfer in DNS", RFC 1995,
|
||||
August 1996.
|
||||
[RFC1996] Vixie, P., "A Mechanism for Prompt Notification of Zone
|
||||
|
|
@ -900,9 +971,8 @@ Additionally, these documents can be obtained via the IETF web site.
|
|||
[RFC2845] Vixie, P., Gudmundsson, O., Eastlake 3rd, D., and B.
|
||||
Wellington, "Secret Key Transaction Authentication for DNS
|
||||
(TSIG)", RFC 2845, May 2000.
|
||||
[RFC2929] Eastlake 3rd, D., Brunner-Williams, E., and B. Manning,
|
||||
"Domain Name System (DNS) IANA Considerations", BCP 42, RFC
|
||||
2929, September 2000.
|
||||
[RFC5395] Eastlake 3rd, "Domain Name System (DNS) IANA Considerations",
|
||||
BCP 42, RFC 5395, November 2008.
|
||||
[RFC2930] Eastlake 3rd, D., "Secret Key Establishment for DNS (TKEY
|
||||
RR)", RFC 2930, September 2000.
|
||||
[RFC2931] Eastlake 3rd, D., "DNS Request and Transaction Signatures
|
||||
|
|
@ -925,10 +995,12 @@ Additionally, these documents can be obtained via the IETF web site.
|
|||
[DNSFLGS] http://www.iana.org/assignments/dns-header-flags
|
||||
[DNSVALS] http://www.iana.org/assignments/dns-parameters
|
||||
|
||||
12.2 Informative
|
||||
13.2 Informative
|
||||
|
||||
[BCP14] Bradner, S., "Key words for use in RFCs to Indicate
|
||||
Requirement Levels", BCP 14, RFC 2119, March 1997.
|
||||
[RFC1700] J. Reynolds and J. Postel, "Assigned Numbers", RFC 1700,
|
||||
October 1994.
|
||||
[RFC2764] Gleeson, B., Lin, A., Heinanen, J., Armitage, G., and A.
|
||||
Malis, "A Framework for IP Based Virtual Private Networks",
|
||||
RFC 2764, February 2000.
|
||||
|
|
@ -936,7 +1008,7 @@ Additionally, these documents can be obtained via the IETF web site.
|
|||
"Internationalizing Domain Names in Applications (IDNA)", RFC
|
||||
3490, March 2003.
|
||||
|
||||
13 Editor's Address
|
||||
14 Editor's Address
|
||||
|
||||
Edward Lewis
|
||||
46000 Center Oak Plaza
|
||||
|
|
@ -944,49 +1016,7 @@ Sterling, VA, 22033, US
|
|||
+1-571-434-5468
|
||||
ed.lewis@neustar.biz
|
||||
|
||||
Full Copyright Statement
|
||||
|
||||
Copyright (C) The IETF Trust (2008).
|
||||
|
||||
This document is subject to the rights, licenses and restrictions
|
||||
contained in BCP 78, and except as set forth therein, the authors
|
||||
retain all their rights.
|
||||
|
||||
This document and the information contained herein are provided on an
|
||||
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
|
||||
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
|
||||
THE INTERNET ENGINEERING TASK FORCE DISCLAIM 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.
|
||||
|
||||
Intellectual Property
|
||||
|
||||
The IETF takes no position regarding the validity or scope of any
|
||||
Intellectual Property Rights or other rights that might be claimed to
|
||||
pertain to the implementation or use of the technology described in
|
||||
this document or the extent to which any license under such rights
|
||||
might or might not be available; nor does it represent that it has
|
||||
made any independent effort to identify any such rights. Information
|
||||
on the procedures with respect to rights in RFC documents can be
|
||||
found in BCP 78 and BCP 79.
|
||||
|
||||
Copies of IPR disclosures made to the IETF Secretariat and any
|
||||
assurances of licenses to be made available, or the result of an
|
||||
attempt made to obtain a general license or permission for the use of
|
||||
such proprietary rights by implementers or users of this
|
||||
specification can be obtained from the IETF on-line IPR repository at
|
||||
http://www.ietf.org/ipr.
|
||||
|
||||
The IETF invites any interested party to bring to its attention any
|
||||
copyrights, patents or patent applications, or other proprietary
|
||||
rights that may cover technology that may be required to implement
|
||||
this standard. Please address the information to the IETF at
|
||||
ietf-ipr@ietf.org.
|
||||
|
||||
Acknowledgment
|
||||
|
||||
Funding for the RFC Editor function is provided by the IETF
|
||||
Administrative Support Activity (IASA).
|
||||
|
||||
|
||||
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Reference in a new issue