draft-ietf-dnsext-rfc6195bis-01.txt   draft-ietf-dnsext-rfc6195bis-02.txt 
INTERNET-DRAFT Donald Eastlake INTERNET-DRAFT Donald Eastlake
Obsoletes: 6195 Huawei Obsoletes: 6195 Huawei
Updates: 1183, 3597 Updates: 1183, 3597
Intended status: Best Current Practice Intended status: Best Current Practice
Expires: November 1, 2012 May 2, 2012 Expires: December 9, 2012 June 10, 2012
Domain Name System (DNS) IANA Considerations Domain Name System (DNS) IANA Considerations
<draft-ietf-dnsext-rfc6195bis-01.txt> <draft-ietf-dnsext-rfc6195bis-02.txt>
Abstract Abstract
This document specifies Internet Assigned Number Authority (IANA) This document specifies Internet Assigned Number Authority (IANA)
parameter assignment considerations for the allocation of Domain Name parameter assignment considerations for the allocation of Domain Name
System (DNS) resource record types, CLASSes, operation codes, error System (DNS) resource record types, CLASSes, operation codes, error
codes, DNS protocol message header bits, and AFSDB resource record codes, DNS protocol message header bits, and AFSDB resource record
subtypes. It obsoletes RFC 6195. subtypes. It obsoletes RFC 6195 and updates RFCs 1183 and 3597.
Status of This Memo Status of This Memo
This Internet-Draft is submitted to IETF in full conformance with the This Internet-Draft is submitted to IETF in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Distribution of this draft is unlimited. It is intended to become the Distribution of this draft is unlimited. It is intended to become the
new BCP 42 obsoleting RFC 6195. Comments should be sent to the DNS new BCP 42 obsoleting RFC 6195. Comments should be sent to the DNS
Extensions Working Group mailing list <dnsext@ietf.org>. Extensions Working Group mailing list <dnsext@ietf.org>.
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Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet- other groups may also distribute working documents as Internet-
Drafts. Drafts.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html http://www.ietf.org/1id-abstracts.html. The list of Internet-Draft
Shadow Directories can be accessed at
The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html.
http://www.ietf.org/shadow.html
INTERNET-DRAFT DNS IANA Considerations INTERNET-DRAFT DNS IANA Considerations
Table of Contents Table of Contents
1. Introduction............................................3 1. Introduction............................................3
1.1. Terminology...........................................3 1.1 Terminology............................................3
1.2 Acknowledgement........................................3 1.2 Acknowledgement........................................3
2. DNS Query/Response Headers..............................4 2. DNS Query/Response Headers..............................4
2.1. One Spare Bit?........................................4 2.1 One Spare Bit?.........................................4
2.2. OpCode Assignment.....................................5 2.2 OpCode Assignment......................................5
2.3. RCODE Assignment......................................5 2.3 RCODE Assignment.......................................5
3. DNS Resource Records....................................7 3. DNS Resource Records....................................7
3.1. RRTYPE IANA Considerations............................8 3.1 RRTYPE IANA Considerations.............................8
3.1.1. DNS RRTYPE Allocation Policy........................9 3.1.1 DNS RRTYPE Allocation Policy.........................9
3.1.2. DNS RRTYPE Expert Guidelines.......................10 3.1.2 DNS RRTYPE Expert Guidelines........................10
3.1.3. Special Note on the OPT RR.........................10 3.1.3 Special Note on the OPT RR..........................10
3.1.4. The AFSDB RR Subtype Field.........................11 3.1.4 The AFSDB RR Subtype Field..........................11
3.2. RR CLASS IANA Considerations.........................11 3.2 RR CLASS IANA Considerations..........................11
3.3. Label Considerations.................................13 3.3. Label Considerations.................................13
3.3.1. Label Types........................................13 3.3.1 Label Types.........................................13
3.3.2. Label Contents and Use.............................13 3.3.2 Label Contents and Use..............................13
4. Security Considerations................................14 4. Security Considerations................................15
5. IANA Considerations....................................14 5. IANA Considerations....................................15
Appendix A: RRTYPE Allocation Template....................15 Appendix A: RRTYPE Allocation Template....................16
Appendix B: Changes From RFC 6195.........................16 Appendix B: Changes From RFC 6195.........................17
Normative References......................................17 Normative References......................................18
Informative References....................................18 Informative References....................................19
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1. Introduction 1. Introduction
The Domain Name System (DNS) provides replicated distributed secure The Domain Name System (DNS) provides replicated distributed secure
hierarchical databases that store "resource records" (RRs) under hierarchical databases that store "resource records" (RRs) under
domain names. DNS data is structured into CLASSes and zones that can domain names. DNS data is structured into CLASSes and zones that can
be independently maintained. Familiarity with [RFC1034], [RFC1035], be independently maintained. Familiarity with [RFC1034], [RFC1035],
[RFC2136], [RFC2181], and [RFC4033] is assumed. [RFC2136], [RFC2181], and [RFC4033] is assumed.
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query/response OpCode for such considerations if they have been query/response OpCode for such considerations if they have been
defined, except for AFSDB RR considerations [RFC1183], which are defined, except for AFSDB RR considerations [RFC1183], which are
included herein. This RFC obsoletes [RFC6195]; however, the only included herein. This RFC obsoletes [RFC6195]; however, the only
significant changes are those to the RRTYPE IANA allocation process, significant changes are those to the RRTYPE IANA allocation process,
aimed at streamlining it and clarifying the expected behavior of the aimed at streamlining it and clarifying the expected behavior of the
parties involved, and the closing of the AFSDB sub-type registry. parties involved, and the closing of the AFSDB sub-type registry.
IANA currently maintains a web page of DNS parameters available from IANA currently maintains a web page of DNS parameters available from
http://www.iana.org. http://www.iana.org.
1.1. Terminology 1.1 Terminology
"Standards Action", "IETF Review", "Specification Required", and "Standards Action", "IETF Review", "Specification Required", and
"Private Use" are as defined in [RFC5226]. "Private Use" are as defined in [RFC5226].
1.2 Acknowledgement 1.2 Acknowledgement
Alfred Hoenes contributions are gratefully acknowledged. Alfred Hoenes contributions are gratefully acknowledged.
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Action. Action.
The unsigned integer fields query count (QDCOUNT), answer count The unsigned integer fields query count (QDCOUNT), answer count
(ANCOUNT), authority count (NSCOUNT), and additional information (ANCOUNT), authority count (NSCOUNT), and additional information
count (ARCOUNT) express the number of records in each section for all count (ARCOUNT) express the number of records in each section for all
OpCodes except Update [RFC2136]. These fields have the same structure OpCodes except Update [RFC2136]. These fields have the same structure
and data type for Update but are instead the counts for the zone and data type for Update but are instead the counts for the zone
(ZOCOUNT), prerequisite (PRCOUNT), update (UPCOUNT), and additional (ZOCOUNT), prerequisite (PRCOUNT), update (UPCOUNT), and additional
information (ARCOUNT) sections. information (ARCOUNT) sections.
2.1. One Spare Bit? 2.1 One Spare Bit?
There have been ancient DNS implementations for which the Z bit being There have been ancient DNS implementations for which the Z bit being
on in a query meant that only a response from the primary server for on in a query meant that only a response from the primary server for
a zone is acceptable. It is believed that current DNS implementations a zone is acceptable. It is believed that current DNS implementations
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ignore this bit. ignore this bit.
Assigning a meaning to the Z bit requires a Standards Action. Assigning a meaning to the Z bit requires a Standards Action.
2.2. OpCode Assignment 2.2 OpCode Assignment
Currently, DNS OpCodes are assigned as follows: Currently, DNS OpCodes are assigned as follows:
OpCode Name Reference OpCode Name Reference
0 Query [RFC1035] 0 Query [RFC1035]
1 IQuery (Inverse Query, Obsolete) [RFC3425] 1 IQuery (Inverse Query, Obsolete) [RFC3425]
2 Status [RFC1035] 2 Status [RFC1035]
3 available for assignment 3 available for assignment
4 Notify [RFC1996] 4 Notify [RFC1996]
5 Update [RFC2136] 5 Update [RFC2136]
6-15 available for assignment 6-15 available for assignment
New OpCode assignments require a Standards Action as modified by New OpCode assignments require a Standards Action as modified by
[RFC4020]. [RFC4020].
2.3. RCODE Assignment 2.3 RCODE Assignment
It would appear from the DNS header above that only four bits of It would appear from the DNS header above that only four bits of
RCODE, or response/error code, are available. However, RCODEs can RCODE, or response/error code, are available. However, RCODEs can
appear not only at the top level of a DNS response but also inside appear not only at the top level of a DNS response but also inside
OPT RRs [RFC2671bis], TSIG RRs [RFC2845], and TKEY RRs [RFC2930]. The OPT RRs [RFC2671bis], TSIG RRs [RFC2845], and TKEY RRs [RFC2930]. The
OPT RR provides an 8-bit extension resulting in a 12-bit RCODE field, OPT RR provides an 8-bit extension resulting in a 12-bit RCODE field,
and the TSIG and TKEY RRs have a 16-bit RCODE field. and the TSIG and TKEY RRs have a 16-bit RCODE field.
Error codes appearing in the DNS header and in these three RR types 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 all refer to the same error code space with the single exception of
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RDLENGTH is an unsigned 16-bit integer that specifies the length in RDLENGTH is an unsigned 16-bit integer that specifies the length in
octets of the RDATA field. octets of the RDATA field.
RDATA is a variable-length string of octets that constitutes the RDATA is a variable-length string of octets that constitutes the
resource. The format of this information varies according to the TYPE resource. The format of this information varies according to the TYPE
and, in some cases, the CLASS of the resource record. and, in some cases, the CLASS of the resource record.
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3.1. RRTYPE IANA Considerations 3.1 RRTYPE IANA Considerations
There are three subcategories of RRTYPE numbers: data TYPEs, QTYPEs, There are three subcategories of RRTYPE numbers: data TYPEs, QTYPEs,
and Meta-TYPEs. and Meta-TYPEs.
Data TYPEs are the means of storing data. QTYPES can only be used in Data TYPEs are the means of storing data. QTYPES can only be used in
queries. Meta-TYPEs designate transient data associated with a queries. Meta-TYPEs designate transient data associated with a
particular DNS message and, in some cases, can also be used in particular DNS message and, in some cases, can also be used in
queries. Thus far, data TYPEs have been assigned from 1 upward, plus queries. Thus far, data TYPEs have been assigned from 1 upward, plus
the block from 100 through 103, and from 32,768 upward, while Q and the block from 100 through 103, and from 32,768 upward, while Q and
Meta-TYPEs have been assigned from 255 downward except for the OPT Meta-TYPEs have been assigned from 255 downward except for the OPT
Meta-RR, which is assigned TYPE 41. There have been DNS Meta-RR, which is assigned TYPE 41. There have been DNS
implementations that made caching decisions based on the top bit of implementations that made caching decisions based on the top bit of
the bottom byte of the RRTYPE. the bottom byte of the RRTYPE.
There are currently three Meta-TYPEs assigned: OPT [RFC2671bis], TSIG There are currently three Meta-TYPEs assigned: OPT [RFC2671bis], TSIG
[RFC2845], and TKEY [RFC2930]. There are currently five QTYPEs [RFC2845], and TKEY [RFC2930]. There are currently five QTYPEs
assigned: * (ALL), MAILA, MAILB, AXFR, and IXFR. assigned: * (ALL), MAILA, MAILB, AXFR, and IXFR.
RRTYPEs have mnemonics that must be completely disjoint from the Allocated RRTYPEs have mnemonics that must be completely disjoint
mnemonics used for CLASSes and that must match the following regular from the mnemonics used for CLASSes and that must match the regular
expression: expression below. In addition, the generic CLASS and RRTYPE names
specified in Section 5 of [RFC3597] cannot be assigned as new RRTYPE
mnemonics.
[A-Z][A-Z0-9\-]*[A-Z0-9] [A-Z][A-Z0-9\-]*[A-Z0-9]
but not
(TYPE|CLASS)(0|[1-9][0-9]*)
Considerations for the allocation of new RRTYPEs are as follows: Considerations for the allocation of new RRTYPEs are as follows:
Decimal Decimal
Hexadecimal Assignment Policy Hexadecimal Assignment Policy
0 0
0x0000 RRTYPE zero is used as a special indicator for the 0x0000 RRTYPE zero is used as a special indicator for the
SIG (0) RR [RFC2931] [RFC4034] and in other SIG (0) RR [RFC2931] [RFC4034] and in other
circumstances, and it must never be allocated for circumstances, and it must never be allocated for
ordinary use. ordinary use.
1 - 127 1 - 127
0x0001 - 0x007F Remaining RRTYPEs in this range are assigned for 0x0001 - 0x007F Remaining RRTYPEs in this range are assigned for
data TYPEs by the DNS RRTYPE Allocation Policy as data TYPEs by the DNS RRTYPE Allocation Policy as
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0xF000 - 0xFEFF Reserved for future use. IETF Review required to 0xF000 - 0xFEFF Reserved for future use. IETF Review required to
define use. define use.
65,280 - 65,534 65,280 - 65,534
0xFF00 - 0xFFFE Private Use. 0xFF00 - 0xFFFE Private Use.
65,535 65,535
0xFFFF Reserved, can only be assigned by a Standards 0xFFFF Reserved, can only be assigned by a Standards
Action. Action.
3.1.1. DNS RRTYPE Allocation Policy 3.1.1 DNS RRTYPE Allocation Policy
Parameter values specified in Section 3.1 above, as assigned based on Parameter values specified in Section 3.1 above as assigned based on
DNS RRTYPE Allocation Policy, are allocated by Expert Review if they DNS RRTYPE Allocation Policy, are allocated by Expert Review if they
meet the two requirements listed below. There will be a pool of a meet the two requirements listed below. There will be a pool of a
small number of Experts appointed by the IESG. Each application will small number of Experts appointed by the IESG. Each application will
be judged by an Expert selected by IANA. In any case where the be judged by an Expert selected by IANA. In any case where the
selected Expert is unavailable or states they have a conflict of selected Expert is unavailable or states they have a conflict of
interest, IANA may select another Expert from the pool. interest, IANA may select another Expert from the pool. Some
guidelines for the Experts are given in Section 3.1.2.
Some guidelines for the Experts are given in Section 3.1.2. RRTYPEs RRTYPEs that do not meet the requirements below may nonetheless be
that do not meet the requirements below may nonetheless be allocated allocated by a Standards Action as modified by [RFC4020].
by a Standards Action as modified by [RFC4020].
1. A complete template as specified in Appendix A has been posted to 1. A complete template as specified in Appendix A has been posted to
the dns-rrtype-applications@iana.org mailing list and received by the dns-rrtype-applications@iana.org mailing list and received by
the Expert. the Expert.
Note that the posting of partially completed, draft, or Note that the posting of partially completed, draft, or
formally submitted templates to dnsext@ietf.org by the applicant formally submitted templates to dnsext@ietf.org by the applicant
or Expert for comment and discussion is highly encouraged. Formal or Expert for comment and discussion is highly encouraged. Formal
submission of an RRTYPE template without consideration of some submission of an RRTYPE template without consideration of some
community review can be expected to increase the probability of community review can be expected to increase the probability of
initial rejection leading to a need to re-submit after initial rejection leading to a need to re-submit after
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should consult with other technical experts and the dnsext@ietf.org should consult with other technical experts and the dnsext@ietf.org
mailing list as necessary. If the Expert does not approve the mailing list as necessary. If the Expert does not approve the
application within this period, it is considered rejected. IANA application within this period, it is considered rejected. IANA
should report non-responsive Experts to the IESG. should report non-responsive Experts to the IESG.
IANA shall maintain a public archive of approved templates. In IANA shall maintain a public archive of approved templates. In
addition, if the required description of the RRTYPE applied for is addition, if the required description of the RRTYPE applied for is
referenced by URL, a copy of the document so referenced should be referenced by URL, a copy of the document so referenced should be
included in the archive. included in the archive.
3.1.2. DNS RRTYPE Expert Guidelines 3.1.2 DNS RRTYPE Expert Guidelines
The Expert should normally reject any RRTYPE allocation request that The Expert should normally reject any RRTYPE allocation request that
meets one or more of the following criteria: meets one or more of the following criteria:
1. Was documented in a manner that was not sufficiently clear or 1. Was documented in a manner that was not sufficiently clear or
complete to evaluate or implement. (Additional documentation can complete to evaluate or implement. (Additional documentation can
be provided during the Expert review period.) be provided during the Expert review period.)
2. The proposed RRTYPE or RRTYPEs affect DNS processing and do not 2. The proposed RRTYPE or RRTYPEs affect DNS processing and do not
meet the criteria in point 2 of Section 3.1.1 above. meet the criteria in point 2 of Section 3.1.1 above.
3. Application use as documented makes incorrect assumptions about 3. Application use as documented makes incorrect assumptions about
DNS protocol behavior, such as wild cards, CNAME, DNAME, etc. DNS protocol behavior, such as wild cards, CNAME, DNAME, etc.
4. An excessive number of RRTYPE values is being requested when the 4. An excessive number of RRTYPE values is being requested when the
purpose could be met with a smaller number or with Private Use purpose could be met with a smaller number or with Private Use
values. values.
3.1.3. Special Note on the OPT RR 3.1.3 Special Note on the OPT RR
The OPT (OPTion) RR (RRTYPE 41) and its IANA considerations are The OPT (OPTion) RR (RRTYPE 41) and its IANA considerations are
specified in [RFC2671bis]. Its primary purpose is to extend the specified in [RFC2671bis]. Its primary purpose is to extend the
effective field size of various DNS fields including RCODE, label effective field size of various DNS fields including RCODE, label
type, OpCode, flag bits, and RDATA size. In particular, for resolvers type, OpCode, flag bits, and RDATA size. In particular, for resolvers
and servers that recognize it, it extends the RCODE field from 4 to and servers that recognize it, it extends the RCODE field from 4 to
12 bits. 12 bits.
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3.1.4. The AFSDB RR Subtype Field 3.1.4 The AFSDB RR Subtype Field
The AFSDB RR [RFC1183] is a CLASS-insensitive RR that has the same The AFSDB RR [RFC1183] is a CLASS-insensitive RR that has the same
RDATA field structure as the MX RR [RFC1035], but the 16-bit unsigned RDATA field structure as the MX RR [RFC1035], but the 16-bit unsigned
integer field at the beginning of the RDATA is interpreted as a integer field at the beginning of the RDATA is interpreted as a
subtype as show below. This subtype registry is closed and allocation subtype as shown below. This subtype registry is closed and
of new subtypes is no longer permitted. allocation of new subtypes is no longer permitted.
Decimal Decimal
Hexadecimal Assignment Policy Hexadecimal Assignment Policy
0 0
0x0000 Reserved, registry closed 0x0000 Reserved, registry closed
1 1
0x0001 AFS v3.0 Location Service [RFC1183] 0x0001 AFS v3.0 Location Service [RFC1183]
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3 - 65,279 3 - 65,279
0x0003 - 0xFEFF Not allocated, registry closed 0x0003 - 0xFEFF Not allocated, registry closed
65,280 - 65,534 65,280 - 65,534
0xFF00 - 0xFFFE Private Use 0xFF00 - 0xFFFE Private Use
65,535 65,535
0xFFFF Reserved, registry closed 0xFFFF Reserved, registry closed
3.2. RR CLASS IANA Considerations 3.2 RR CLASS IANA Considerations
There are currently two subcategories of DNS CLASSes: normal, data- There are currently two subcategories of DNS CLASSes: normal, data-
containing classes and QCLASSes that are only meaningful in queries containing classes and QCLASSes that are only meaningful in queries
or updates. or updates.
DNS CLASSes have been little used but constitute another dimension of DNS CLASSes have been little used but constitute another dimension of
the DNS distributed database. In particular, there is no necessary the DNS distributed database. In particular, there is no necessary
relationship between the name space or root servers for one data relationship between the name space or root servers for one data
CLASS and those for another data CLASS. The same DNS NAME can have CLASS and those for another data CLASS. The same DNS NAME can have
completely different meanings in different CLASSes. The label types completely different meanings in different CLASSes. The label types
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As yet, there has not been a requirement for "meta-CLASSes". That As yet, there has not been a requirement for "meta-CLASSes". That
would be a CLASS to designate transient data associated with a would be a CLASS to designate transient data associated with a
particular DNS message, which might be usable in queries. However, it particular DNS message, which might be usable in queries. However, it
is possible that there might be a future requirement for one or more is possible that there might be a future requirement for one or more
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"meta-CLASSes". "meta-CLASSes".
CLASSes have mnemonics that must be completely disjoint from the Assigned CLASSes have mnemonics that must be completely disjoint from
mnemonics used for RRTYPEs and that must match the following regular the mnemonics used for RRTYPEs and that must match the regular
expression: expression below. In addition, the generic CLASS and RRTYPE names
specified in Section 5 of [RFC3597] cannot be assigned as new CLASS
mnemonics.
[A-Z][A-Z0-9\-]*[A-Z0-9] [A-Z][A-Z0-9\-]*[A-Z0-9]
but not
(CLASS|RRTYPE)(0|[1-9][0-9]*)
The current CLASS assignments and considerations for future The current CLASS assignments and considerations for future
assignments are as follows: assignments are as follows:
Decimal Decimal
Hexadecimal Assignment / Policy, Reference Hexadecimal Assignment / Policy, Reference
0 0
0x0000 Reserved; assignment requires a Standards Action 0x0000 Reserved; assignment requires a Standards Action
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254 254
0x00FE QCLASS NONE [RFC2136] 0x00FE QCLASS NONE [RFC2136]
255 255
0x00FF QCLASS * (ANY) [RFC1035] 0x00FF QCLASS * (ANY) [RFC1035]
256 - 32,767 256 - 32,767
0x0100 - 0x7FFF Available for assignment by IETF Review 0x0100 - 0x7FFF Available for assignment by IETF Review
32,768 - 57,343
0x8000 - 0xDFFF Assigned for data CLASSes only; Specification
Required for new assignments
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32,768 - 57,343
0x8000 - 0xDFFF Available for assignment to data CLASSes only;
Specification Required
57,344 - 65,279 57,344 - 65,279
0xE000 - 0xFEFF Assigned for QCLASSes and meta-CLASSes only; 0xE000 - 0xFEFF Available for assignment to QCLASSes and meta-
Specification Required for new assignments CLASSes only; Specification Required
65,280 - 65,534 65,280 - 65,534
0xFF00 - 0xFFFE Private Use 0xFF00 - 0xFFFE Private Use
65,535 65,535
0xFFFF Reserved; can only be assigned by a Standards 0xFFFF Reserved; can only be assigned by a Standards
Action Action
3.3. Label Considerations 3.3. Label Considerations
DNS NAMEs are sequences of labels [RFC1035]. DNS NAMEs are sequences of labels [RFC1035].
3.3.1. Label Types 3.3.1 Label Types
At the present time, there are two categories of label types: data At the present time, there are two categories of label types: data
labels and compression labels. Compression labels are pointers to labels and compression labels. Compression labels are pointers to
data labels elsewhere within an RR or DNS message and are intended to data labels elsewhere within an RR or DNS message and are intended to
shorten the wire encoding of NAMEs. shorten the wire encoding of NAMEs.
The two existing data label types are sometimes referred to as Text The two existing data label types are sometimes referred to as Text
and Binary. Text labels can, in fact, include any octet value and Binary. Text labels can, in fact, include any octet value
including zero-value octets, but many current uses involve only including zero-value octets, but many current uses involve only
printing ASCII characters [RFC20]. For retrieval, Text labels are printing ASCII characters [US-ASCII]. For retrieval, Text labels are
defined to treat ASCII upper and lower case letter codes as matching defined to treat ASCII upper and lower case letter codes as matching
[RFC4343]. Binary labels are bit sequences [RFC2673]. The Binary [RFC4343]. Binary labels are bit sequences [RFC2673]. The Binary
label type is Historic [RFC2671bis]. label type is Historic [RFC2671bis].
3.3.2. Label Contents and Use 3.3.2 Label Contents and Use
The last label in each NAME is "ROOT", which is the zero-length The last label in each NAME is "ROOT", which is the zero-length
label. By definition, the null or ROOT label cannot be used for any label. By definition, the null or ROOT label cannot be used for any
other NAME purpose. other NAME purpose.
NAMEs are local to a CLASS. The Hesiod [Dyer1987] and Chaos NAMEs are local to a CLASS. The Hesiod [Dyer1987] and Chaos
[Moon1981] CLASSes are for essentially local use. The IN, or [Moon1981] CLASSes are for essentially local use. The IN, or
Internet, CLASS is thus the only DNS CLASS in global use on the Internet, CLASS is thus the only DNS CLASS in global use on the
Internet at this time. Internet at this time.
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A somewhat out-of-date description of name allocation in the IN Class A somewhat out-of-date description of name allocation in the IN Class
is given in [RFC1591]. Some information on reserved top-level domain is given in [RFC1591]. Some information on reserved top-level domain
names is in BCP 32 [RFC2606]. names is in BCP 32 [RFC2606].
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4. Security Considerations 4. Security Considerations
This document addresses IANA considerations in the allocation of This document addresses IANA considerations in the allocation of
general DNS parameters, not security. See [RFC4033], [RFC4034], and general DNS parameters, not security. See [RFC4033], [RFC4034], and
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I. Does the proposal require/expect any changes in DNS I. Does the proposal require/expect any changes in DNS
servers/resolvers that prevent the new type from being processed servers/resolvers that prevent the new type from being processed
as an unknown RRTYPE (see [RFC3597])? as an unknown RRTYPE (see [RFC3597])?
J. Comments: J. Comments:
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Appendix B: Changes From RFC 6195 Appendix B: Changes From RFC 6195
Drop description of changes from RFC 5395 to RFC 6195 since those Drop description of changes from RFC 5395 to [RFC6195] since those
changes have already happened and we don't need to do them again. Add changes have already happened and we don't need to do them again. Add
description of changes from RFC 6195. description of changes from [RFC6195] to this document.
Cut back RRTYPE Expert review period to two weeks and eliminate the Cut back RRTYPE Expert review period to two weeks and eliminate the
mandatory dnsext@ietf.org comment period. Change workflow description mandatory dnsext@ietf.org comment period. Change workflow description
for RRTYPE review and allocation to correspond more closely to actual for RRTYPE review and allocation to correspond more closely to actual
practice. practice.
Close AFSDB sub-type registry. Close the AFSDB sub-type registry.
Update references for revised versions and change ASCII reference to Update references for revised versions.
[RFC20].
Clarify IANA archiving of referenced documentation as well as Clarify IANA archiving of referenced documentation as well as
approved RRTYPE application template. approved RRTYPE application template.
In the RRTYPE application template, change the label of question "B" In the RRTYPE application template, change the label of question "B"
to "B.1" and add "B.2" to ask about the kind of RR. to "B.1" and add "B.2" to ask about the kind of RR.
Addition of text and an exclusory regular expression to Sections 3.1
and 3.2 to prohibit the use of the generic CLASS and RRTYPE names
specified in [RFC3597] as the mnemonics for new CLASSes and RRTYPEes.
A number of editorial changes and typo fixes. A number of editorial changes and typo fixes.
INTERNET-DRAFT DNS IANA Considerations INTERNET-DRAFT DNS IANA Considerations
Normative References Normative References
[RFC20] - Cerf, V., "ASCII format for network interchange", RFC 20,
October 1969.
[RFC1034] - Mockapetris, P., "Domain names - concepts and [RFC1034] - Mockapetris, P., "Domain names - concepts and
facilities", STD 13, RFC 1034, November 1987. facilities", STD 13, RFC 1034, November 1987.
[RFC1035] - Mockapetris, P., "Domain names - implementation and [RFC1035] - Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987. specification", STD 13, RFC 1035, November 1987.
[RFC1996] - Vixie, P., "A Mechanism for Prompt Notification of Zone [RFC1996] - Vixie, P., "A Mechanism for Prompt Notification of Zone
Changes (DNS NOTIFY)", RFC 1996, August 1996. Changes (DNS NOTIFY)", RFC 1996, August 1996.
[RFC2136] - Vixie, P., Ed., Thomson, S., Rekhter, Y., and J. Bound, [RFC2136] - Vixie, P., Ed., Thomson, S., Rekhter, Y., and J. Bound,
"Dynamic Updates in the Domain Name System (DNS UPDATE)", RFC 2136, "Dynamic Updates in the Domain Name System (DNS UPDATE)",
April 1997. RFC 2136, April 1997.
[RFC2181] - Elz, R. and R. Bush, "Clarifications to the DNS [RFC2181] - Elz, R. and R. Bush, "Clarifications to the DNS
Specification", RFC 2181, July 1997. Specification", RFC 2181, July 1997.
[RFC2845] - Vixie, P., Gudmundsson, O., Eastlake 3rd, D., and B. [RFC2845] - Vixie, P., Gudmundsson, O., Eastlake 3rd, D., and B.
Wellington, "Secret Key Transaction Authentication for DNS (TSIG)", Wellington, "Secret Key Transaction Authentication for
RFC 2845, May 2000. DNS (TSIG)", RFC 2845, May 2000.
[RFC2930] - Eastlake 3rd, D., "Secret Key Establishment for DNS (TKEY [RFC2930] - Eastlake 3rd, D., "Secret Key Establishment for DNS (TKEY
RR)", RFC 2930, September 2000. RR)", RFC 2930, September 2000.
[RFC3425] - Lawrence, D., "Obsoleting IQUERY", RFC 3425, November [RFC3425] - Lawrence, D., "Obsoleting IQUERY", RFC 3425, November
2002. 2002.
[RFC3597] - Gustafsson, A., "Handling of Unknown DNS Resource Record [RFC3597] - Gustafsson, A., "Handling of Unknown DNS Resource Record
(RR) Types", RFC 3597, September 2003. (RR) Types", RFC 3597, September 2003.
[RFC4020] - Kompella, K. and A. Zinin, "Early IANA Allocation of [RFC4020] - Kompella, K. and A. Zinin, "Early IANA Allocation of
Standards Track Code Points", BCP 100, RFC 4020, February 2005. Standards Track Code Points", BCP 100, RFC 4020, February
2005.
[RFC4033] - Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4033] - Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "DNS Security Introduction and Requirements", RFC 4033, March Rose, "DNS Security Introduction and Requirements", RFC
2005. 4033, March 2005.
[RFC4034] - Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4034] - Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Resource Records for the DNS Security Extensions", RFC 4034, Rose, "Resource Records for the DNS Security Extensions",
March 2005. RFC 4034, March 2005.
[RFC4035] - Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4035] - Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Protocol Modifications for the DNS Security Extensions", RFC Rose, "Protocol Modifications for the DNS Security
4035, March 2005. Extensions", RFC 4035, March 2005.
INTERNET-DRAFT DNS IANA Considerations
[RFC4635] - Eastlake 3rd, D., "HMAC SHA (Hashed Message [RFC4635] - Eastlake 3rd, D., "HMAC SHA (Hashed Message
Authentication Code, Secure Hash Algorithm) TSIG Algorithm Authentication Code, Secure Hash Algorithm) TSIG
Identifiers", RFC 4635, August 2006. Algorithm Identifiers", RFC 4635, August 2006.
INTERNET-DRAFT DNS IANA Considerations
[RFC5226] - Narten, T. and H. Alvestrand, "Guidelines for Writing an [RFC5226] - Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008. IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
[RFC2671bis] - Damas, J., Graff, M., and Vixie, P., "Extension [RFC2671bis] - Damas, J., Graff, M., and Vixie, P., "Extension
Mechanisms for DNS (EDNS0)", draft-ietf-dnsext-rfc2671bis-edns0, work Mechanisms for DNS (EDNS0)", draft-ietf-dnsext-
in progress. rfc2671bis-edns0, work in progress.
[US-ASCII] - ANSI, "USA Standard Code for Information Interchange",
X3.4, American National Standards Institute: New York,
1968
Informative References Informative References
[Dyer1987] - Dyer, S., and F. Hsu, "Hesiod", Project Athena Technical [Dyer1987] - Dyer, S., and F. Hsu, "Hesiod", Project Athena Technical
Plan - Name Service, April 1987. Plan - Name Service, April 1987.
[Moon1981] - Moon, D., "Chaosnet", A.I. Memo 628, Massachusetts [Moon1981] - Moon, D., "Chaosnet", A.I. Memo 628, Massachusetts
Institute of Technology Artificial Intelligence Laboratory, June Institute of Technology Artificial Intelligence
1981. Laboratory, June 1981.
[RFC1183] - Everhart, C., Mamakos, L., Ullmann, R., and P. [RFC1183] - Everhart, C., Mamakos, L., Ullmann, R., and P.
Mockapetris, "New DNS RR Definitions", RFC 1183, October 1990. Mockapetris, "New DNS RR Definitions", RFC 1183, October
1990.
[RFC1591] - Postel, J., "Domain Name System Structure and [RFC1591] - Postel, J., "Domain Name System Structure and
Delegation", RFC 1591, March 1994. Delegation", RFC 1591, March 1994.
[RFC2606] - Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS [RFC2606] - Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS
Names", BCP 32, RFC 2606, June 1999. Names", BCP 32, RFC 2606, June 1999.
[RFC2673] - Crawford, M., "Binary Labels in the Domain Name System", [RFC2673] - Crawford, M., "Binary Labels in the Domain Name System",
RFC 2673, August 1999. RFC 2673, August 1999.
[RFC2931] - Eastlake 3rd, D., "DNS Request and Transaction Signatures [RFC2931] - Eastlake 3rd, D., "DNS Request and Transaction Signatures
( SIG(0)s )", RFC 2931, September 2000. ( SIG(0)s )", RFC 2931, September 2000.
[RFC4343] - Eastlake 3rd, D., "Domain Name System (DNS) Case [RFC4343] - Eastlake 3rd, D., "Domain Name System (DNS) Case
Insensitivity Clarification", RFC 4343, January 2006. Insensitivity Clarification", RFC 4343, January 2006.
[RFC6195] - Eastlake 3rd, D., "Domain Name System (DNS) IANA [RFC6195] - Eastlake 3rd, D., "Domain Name System (DNS) IANA
Considerations", RFC 6195, March 2011. Considerations", RFC 6195, March 2011.
INTERNET-DRAFT DNS IANA Considerations INTERNET-DRAFT DNS IANA Considerations
Author's Address Author's Address
Donald E. Eastlake 3rd Donald E. Eastlake 3rd
Huawei R&D USA Huawei R&D USA
155 Beaver Street 155 Beaver Street
Milford, MA 01757 USA Milford, MA 01757 USA
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