draft-ietf-dnsext-rfc2538bis-00.txt   draft-ietf-dnsext-rfc2538bis-01.txt 
Network Working Group S. Josefsson Network Working Group S. Josefsson
Expires: July 25, 2005 Expires: July 2, 2005
Storing Certificates in the Domain Name System (DNS) Storing Certificates in the Domain Name System (DNS)
draft-ietf-dnsext-rfc2538bis-00 draft-ietf-dnsext-rfc2538bis-01
Status of this Memo Status of this Memo
This document is an Internet-Draft and is subject to all provisions This document is an Internet-Draft and is subject to all provisions
of section 3 of RFC 3667. By submitting this Internet-Draft, each of section 3 of RFC 3667. By submitting this Internet-Draft, each
author represents that any applicable patent or other IPR claims of 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 is aware have been or will be disclosed, and any of
which he or she become aware will be disclosed, in accordance with which he or she become aware will be disclosed, in accordance with
RFC 3668. RFC 3668.
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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
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The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt. http://www.ietf.org/ietf/1id-abstracts.txt.
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This Internet-Draft will expire on July 25, 2005. This Internet-Draft will expire on July 2, 2005.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2005). Copyright (C) The Internet Society (2005).
Abstract Abstract
Cryptographic public key are frequently published and their Cryptographic public key are frequently published and their
authenticity demonstrated by certificates. A CERT resource record authenticity demonstrated by certificates. A CERT resource record
(RR) is defined so that such certificates and related certificate (RR) is defined so that such certificates and related certificate
revocation lists can be stored in the Domain Name System (DNS). revocation lists can be stored in the Domain Name System (DNS).
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. The CERT Resource Record . . . . . . . . . . . . . . . . . . . 3 2. The CERT Resource Record . . . . . . . . . . . . . . . . . . . 3
2.1 Certificate Type Values . . . . . . . . . . . . . . . . . 4 2.1 Certificate Type Values . . . . . . . . . . . . . . . . . 4
2.2 Text Representation of CERT RRs . . . . . . . . . . . . . 5 2.2 Text Representation of CERT RRs . . . . . . . . . . . . . 5
2.3 X.509 OIDs . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 X.509 OIDs . . . . . . . . . . . . . . . . . . . . . . . . 6
3. Appropriate Owner Names for CERT RRs . . . . . . . . . . . . . 6 3. Appropriate Owner Names for CERT RRs . . . . . . . . . . . . . 6
3.1 Content-based X.509 CERT RR Names . . . . . . . . . . . . 7 3.1 Content-based X.509 CERT RR Names . . . . . . . . . . . . 7
3.2 Purpose-based X.509 CERT RR Names . . . . . . . . . . . . 8 3.2 Purpose-based X.509 CERT RR Names . . . . . . . . . . . . 8
3.3 Content-based OpenPGP CERT RR Names . . . . . . . . . . . 8 3.3 Content-based OpenPGP CERT RR Names . . . . . . . . . . . 8
3.4 Purpose-based OpenPGP CERT RR Names . . . . . . . . . . . 9 3.4 Purpose-based OpenPGP CERT RR Names . . . . . . . . . . . 9
3.5 Owner names for IPKIX, ISPKI, and IPGP . . . . . . . . . . 9
4. Performance Considerations . . . . . . . . . . . . . . . . . . 9 4. Performance Considerations . . . . . . . . . . . . . . . . . . 9
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. Security Considerations . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
8. Changes since RFC 2538 . . . . . . . . . . . . . . . . . . . . 11 8. Changes since RFC 2538 . . . . . . . . . . . . . . . . . . . . 11
Author's Address . . . . . . . . . . . . . . . . . . . . . . . 12 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 12
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11
9.1 Normative References . . . . . . . . . . . . . . . . . . . . 11 9.1 Normative References . . . . . . . . . . . . . . . . . . . . 11
9.2 Informative References . . . . . . . . . . . . . . . . . . . 12 9.2 Informative References . . . . . . . . . . . . . . . . . . . 12
A. Copying conditions . . . . . . . . . . . . . . . . . . . . . . 12 A. Copying conditions . . . . . . . . . . . . . . . . . . . . . . 12
Intellectual Property and Copyright Statements . . . . . . . . 13 Intellectual Property and Copyright Statements . . . . . . . . 14
1. Introduction 1. Introduction
Public keys are frequently published in the form of a certificate and Public keys are frequently published in the form of a certificate and
their authenticity is commonly demonstrated by certificates and their authenticity is commonly demonstrated by certificates and
related certificate revocation lists (CRLs). A certificate is a related certificate revocation lists (CRLs). A certificate is a
binding, through a cryptographic digital signature, of a public key, binding, through a cryptographic digital signature, of a public key,
a validity interval and/or conditions, and identity, authorization, a validity interval and/or conditions, and identity, authorization,
or other information. A certificate revocation list is a list of or other information. A certificate revocation list is a list of
certificates that are revoked, and incidental information, all signed certificates that are revoked, and incidental information, all signed
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2.1 Certificate Type Values 2.1 Certificate Type Values
The following values are defined or reserved: The following values are defined or reserved:
Value Mnemonic Certificate Type Value Mnemonic Certificate Type
----- -------- ----------- ---- ----- -------- ----------- ----
0 reserved 0 reserved
1 PKIX X.509 as per PKIX 1 PKIX X.509 as per PKIX
2 SPKI SPKI certificate 2 SPKI SPKI certificate
3 PGP OpenPGP packet 3 PGP OpenPGP packet
4-252 available for IANA assignment 4 IPKIX The URL of an X.509 data object
5 ISPKI The URL of an SPKI certificate
6 IPGP The URL of an OpenPGP packet
7-252 available for IANA assignment
253 URI URI private 253 URI URI private
254 OID OID private 254 OID OID private
255-65534 available for IANA assignment 255-65534 available for IANA assignment
65535 reserved 65535 reserved
The PKIX type is reserved to indicate an X.509 certificate conforming The PKIX type is reserved to indicate an X.509 certificate conforming
to the profile being defined by the IETF PKIX working group. The to the profile being defined by the IETF PKIX working group. The
certificate section will start with a one byte unsigned OID length certificate section will start with a one byte unsigned OID length
and then an X.500 OID indicating the nature of the remainder of the and then an X.500 OID indicating the nature of the remainder of the
certificate section (see 2.3 below). (NOTE: X.509 certificates do certificate section (see 2.3 below). (NOTE: X.509 certificates do
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The SPKI type is reserved to indicate a certificate formated as to be The SPKI type is reserved to indicate a certificate formated as to be
specified by the IETF SPKI working group. specified by the IETF SPKI working group.
The PGP type indicates an OpenPGP packet as described in [5] and its The PGP type indicates an OpenPGP packet as described in [5] and its
extensions and successors. Two uses are to transfer public key extensions and successors. Two uses are to transfer public key
material and revocation signatures. The data is binary, and MUST NOT material and revocation signatures. The data is binary, and MUST NOT
be encoded into an ASCII armor. An implementation SHOULD process be encoded into an ASCII armor. An implementation SHOULD process
transferable public keys as described in section 10.1 of [5], but it transferable public keys as described in section 10.1 of [5], but it
MAY handle additional OpenPGP packets. MAY handle additional OpenPGP packets.
The IPKIX, ISPKI and IPGP types indicate a URL which will serve the
content that would have been in the "certificate, CRL or URL" field
of the corresponding (PKIX, SPKI or PGP) packet types. These types
are known as "indirect". These packet types MUST be used when the
content is too large to fit in the CERT RR, and MAY be used at the
implementations discretion. They SHOULD NOT be used where the entire
UDP packet would have fit in 512 bytes.
The URI private type indicates a certificate format defined by an The URI private type indicates a certificate format defined by an
absolute URI. The certificate portion of the CERT RR MUST begin with absolute URI. The certificate portion of the CERT RR MUST begin with
a null terminated URI [4] and the data after the null is the private a null terminated URI [4] and the data after the null is the private
format certificate itself. The URI SHOULD be such that a retrieval format certificate itself. The URI SHOULD be such that a retrieval
from it will lead to documentation on the format of the certificate. from it will lead to documentation on the format of the certificate.
Recognition of private certificate types need not be based on URI Recognition of private certificate types need not be based on URI
equality but can use various forms of pattern matching so that, for equality but can use various forms of pattern matching so that, for
example, subtype or version information can also be encoded into the example, subtype or version information can also be encoded into the
URI. URI.
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the character such as \000 for NULL. the character such as \000 for NULL.
The choice of name under which CERT RRs are stored is important to The choice of name under which CERT RRs are stored is important to
clients that perform CERT queries. In some situations, the client clients that perform CERT queries. In some situations, the client
may not know all information about the CERT RR object it wishes to may not know all information about the CERT RR object it wishes to
retrieve. For example, a client may not know the subject name of an retrieve. For example, a client may not know the subject name of an
X.509 certificate, or the e-mail address of the owner of an OpenPGP X.509 certificate, or the e-mail address of the owner of an OpenPGP
key. Further, the client might only know the hostname of a service key. Further, the client might only know the hostname of a service
that uses X.509 certificates or the Key ID of an OpenPGP key. that uses X.509 certificates or the Key ID of an OpenPGP key.
This motivate describing two different owner name guidelines. We This motivates describing two different owner name guidelines. We
call the two rules content-based owner names and purpose-based owner call the two rules content-based owner names and purpose-based owner
names. A content-based owner name is derived from the content of the names. A content-based owner name is derived from the content of the
CERT RR data; for example the Subject field in an X.509 certificate CERT RR data; for example the Subject field in an X.509 certificate
or the User ID field in OpenPGP keys. A purpose-based owner name is or the User ID field in OpenPGP keys. A purpose-based owner name is
selected to be a name that clients that wishes to retrieve CERT RRs selected to be a name that clients that wishes to retrieve CERT RRs
are expected to know; for example the host name of a X.509 protected are expected to know; for example the host name of a X.509 protected
service or a Key ID of an OpenPGP key. Note that in some situations, service or a Key ID of an OpenPGP key. Note that in some situations,
the content-based and purpose-based owner name can be the same; for the content-based and purpose-based owner name can be the same; for
example when a client look up keys based on e-mail addresses for example when a client look up keys based on e-mail addresses for
incoming e-mail. incoming e-mail.
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The recommended locations of CERT storage are as follows, in priority The recommended locations of CERT storage are as follows, in priority
order: order:
1. If a domain name is included in the identification in the 1. If a domain name is included in the identification in the
certificate or CRL, that should be used. certificate or CRL, that should be used.
2. If a domain name is not included but an IP address is included, 2. If a domain name is not included but an IP address is included,
then the translation of that IP address into the appropriate then the translation of that IP address into the appropriate
inverse domain name should be used. inverse domain name should be used.
3. If neither of the above it used but a URI containing a domain 3. If neither of the above it used but a URI containing a domain
name is present, that domain name should be used. name is present, that domain name should be used.
4. If none of the above is included but a character string name is 4. If none of the above is included but a character string name is
included, then it should be treated as described for PGP names included, then it should be treated as described for OpenPGP
below. names below.
5. If none of the above apply, then the distinguished name (DN) 5. If none of the above apply, then the distinguished name (DN)
should be mapped into a domain name as specified in [3]. should be mapped into a domain name as specified in [3].
Example 1: Assume that an X.509v3 certificate is issued to /CN=John Example 1: Assume that an X.509v3 certificate is issued to /CN=John
Doe/DC=Doe/DC=com/DC=xy/O=Doe Inc/C=XY/ with Subject Alternative Doe/DC=Doe/DC=com/DC=xy/O=Doe Inc/C=XY/ with Subject Alternative
names of (a) string "John (the Man) Doe", (b) domain name john- names of (a) string "John (the Man) Doe", (b) domain name john-
doe.com, and (c) uri <https://www.secure.john-doe.com:8080/>. Then doe.com, and (c) uri <https://www.secure.john-doe.com:8080/>. Then
the storage locations recommended, in priority order, would be the storage locations recommended, in priority order, would be
1. john-doe.com, 1. john-doe.com,
2. www.secure.john-doe.com, and 2. www.secure.john-doe.com, and
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Example: A S/MIME certificate for Example: A S/MIME certificate for
"[email protected]" will use a standard "[email protected]" will use a standard
hostname translation of the owner name, hostname translation of the owner name,
i.e. "postmaster.example.org". i.e. "postmaster.example.org".
SSL Certificate Hostname of the SSL server. SSL Certificate Hostname of the SSL server.
IPSEC Certificate Hostname of the IPSEC machine, and/or IPSEC Certificate Hostname of the IPSEC machine, and/or
for the in-addr.arpa reverse lookup IP address. for the in-addr.arpa reverse lookup IP address.
CRLs Hostname of the issuing CA. An alternative approach for IPSEC is to store raw public keys [12].
3.3 Content-based OpenPGP CERT RR Names 3.3 Content-based OpenPGP CERT RR Names
OpenPGP signed keys (certificates) use a general character string OpenPGP signed keys (certificates) use a general character string
User ID [5]. However, it is recommended by OpenPGP that such names User ID [5]. However, it is recommended by OpenPGP that such names
include the RFC 2822 [7] email address of the party, as in "Leslie include the RFC 2822 [7] email address of the party, as in "Leslie
Example <[email protected]>". If such a format is used, the CERT Example <[email protected]>". If such a format is used, the CERT
should be under the standard translation of the email address into a should be under the standard translation of the email address into a
domain name, which would be leslie.host.example in this case. If no domain name, which would be leslie.host.example in this case. If no
RFC 2822 name can be extracted from the string name no specific RFC 2822 name can be extracted from the string name no specific
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If a user has more than one email address, the CNAME type can be used If a user has more than one email address, the CNAME type can be used
to reduce the amount of data stored in the DNS. For example: to reduce the amount of data stored in the DNS. For example:
$ORIGIN example.org. $ORIGIN example.org.
smith IN CERT PGP 0 0 <OpenPGP binary> smith IN CERT PGP 0 0 <OpenPGP binary>
john.smith IN CNAME smith john.smith IN CNAME smith
js IN CNAME smith js IN CNAME smith
3.4 Purpose-based OpenPGP CERT RR Names 3.4 Purpose-based OpenPGP CERT RR Names
Applications that receive an OpenPGP packet but do not know the email Applications that receive an OpenPGP packet containing encrypted or
address of the sender will have difficulties constructing the correct signed data but do not know the email address of the sender will have
owner name, and cannot use the content-based owner name guidelines. difficulties constructing the correct owner name and cannot use the
However, these clients commonly know the key fingerprint or the Key content-based owner name guidelines. However, these clients commonly
ID. The key ID is found in OpenPGP packets, and the key fingerprint know the key fingerprint or the Key ID. The key ID is found in
is commonly found in auxilliary data that may be available. For OpenPGP packets, and the key fingerprint is commonly found in
these situations, it is recommended to use an owner name identical to auxilliary data that may be available. For these situations, it is
the key fingerprint and key ID expressed in hexadecimal [11]. For recommended to use an owner name identical to the key fingerprint and
example: key ID expressed in hexadecimal [11]. For example:
$ORIGIN example.org. $ORIGIN example.org.
0424D4EE81A0E3D119C6F835EDA21E94B565716F IN CERT PGP ... 0424D4EE81A0E3D119C6F835EDA21E94B565716F IN CERT PGP ...
F835EDA21E94B565716F IN CERT PGP ... F835EDA21E94B565716F IN CERT PGP ...
B565716F IN CERT PGP ... B565716F IN CERT PGP ...
If the same key material is stored at several owner names, the use of If the same key material is stored at several owner names, the use of
CNAME may be used to avoid data duplication. Note that CNAME is not CNAME may be used to avoid data duplication. Note that CNAME is not
always applicable, because it map an owner names to the other for all always applicable, because it map an owner names to the other for all
purposes, and this may be sub-optimal when two keys with the same Key purposes, and this may be sub-optimal when two keys with the same Key
ID are stored. ID are stored.
3.5 Owner names for IPKIX, ISPKI, and IPGP
These types are stored under the same owner names, both purpose- and
content-based, as the PKIX, SPKI and PGP types, respectively.
4. Performance Considerations 4. Performance Considerations
Current Domain Name System (DNS) implementations are optimized for Current Domain Name System (DNS) implementations are optimized for
small transfers, typically not more than 512 bytes including small transfers, typically not more than 512 bytes including
overhead. While larger transfers will perform correctly and work is overhead. While larger transfers will perform correctly and work is
underway to make larger transfers more efficient, it is still underway to make larger transfers more efficient, it is still
advisable at this time to make every reasonable effort to minimize advisable at this time to make every reasonable effort to minimize
the size of certificates stored within the DNS. Steps that can be the size of certificates stored within the DNS. Steps that can be
taken may include using the fewest possible optional or extensions taken may include using the fewest possible optional or extensions
fields and using short field values for variable length fields that fields and using short field values for variable length fields that
must be included. must be included.
The RDATA field in the DNS protocol may only hold data of size 65535 The RDATA field in the DNS protocol may only hold data of size 65535
octets (64kb) or less. This means that each CERT RR cannot contain octets (64kb) or less. This means that each CERT RR cannot contain
more than 64kb worth of payload, even if the corresponding more than 64kb worth of payload, even if the corresponding
certificate or certificate revocation list is larger. This document certificate or certificate revocation list is larger. This document
do not address this limitation. address this by defining "indirect" data types for each normal type.
5. Acknowledgements 5. Acknowledgements
The majority of this document is copied verbatim from RFC 2538, by The majority of this document is copied verbatim from RFC 2538, by
Donald Eastlake 3rd and Olafur Gudmundsson. Donald Eastlake 3rd and Olafur Gudmundsson.
The author wishes to thank David Shaw and Michael Graff for their The author wishes to thank David Shaw and Michael Graff for their
contributions to the earlier work that motivated this revised contributions to the earlier work that motivated this revised
document. document.
Florian Weimer suggested to clarify wording regarding what data can This document was improved by suggestions and comments from Olivier
be stored in RRDATA portion of OpenPGP CERT RRs, and that the URI Dubuisson, Ben Laurie, Samuel Weiler, and Florian Weimer. No doubt
type may include hashes to secure the indirection. Olivier Dubuisson the list is incomplete. We apologize to anyone we left out.
confirmed that the X.509 OID were indeed correct.
6. Security Considerations 6. Security Considerations
By definition, certificates contain their own authenticating By definition, certificates contain their own authenticating
signature. Thus it is reasonable to store certificates in non-secure signature. Thus it is reasonable to store certificates in non-secure
DNS zones or to retrieve certificates from DNS with DNS security DNS zones or to retrieve certificates from DNS with DNS security
checking not implemented or deferred for efficiency. The results MAY checking not implemented or deferred for efficiency. The results MAY
be trusted if the certificate chain is verified back to a known be trusted if the certificate chain is verified back to a known
trusted key and this conforms with the user's security policy. trusted key and this conforms with the user's security policy.
Alternatively, if certificates are retrieved from a secure DNS zone Alternatively, if certificates are retrieved from a secure DNS zone
with DNS security checking enabled and are verified by DNS security, with DNS security checking enabled and are verified by DNS security,
the key within the retrieved certificate MAY be trusted without the key within the retrieved certificate MAY be trusted without
verifying the certificate chain if this conforms with the user's verifying the certificate chain if this conforms with the user's
security policy. security policy.
When the URI type is used, it should be understood that is introduce When the URI type is used, it should be understood that it introduces
an additional indirection that may allow for a new attack vector. an additional indirection that may allow for a new attack vector.
One method to secure that indirection is to include a hash of the One method to secure that indirection is to include a hash of the
certificate in the URI itself. certificate in the URI itself.
CERT RRs are not used in connection with securing the DNS security CERT RRs are not used by DNSSEC [8] so there are no security
additions so there are no security considerations related to CERT RRs considerations related to CERT RRs and securing the DNS itself.
and securing the DNS itself.
If DNSSEC [8] is used then the non-existence of a CERT RR, and
consequently certificates or revocation lists, can be securely
asserted. Without DNSSEC, this is not possible.
7. IANA Considerations 7. IANA Considerations
Certificate types 0x0000 through 0x00FF and 0xFF00 through 0xFFFF can Certificate types 0x0000 through 0x00FF and 0xFF00 through 0xFFFF can
only be assigned by an IETF standards action [6]. This document only be assigned by an IETF standards action [6]. This document
assigns 0x0001 through 0x0003 and 0x00FD and 0x00FE. Certificate assigns 0x0001 through 0x0006 and 0x00FD and 0x00FE. Certificate
types 0x0100 through 0xFEFF are assigned through IETF Consensus [6] types 0x0100 through 0xFEFF are assigned through IETF Consensus [6]
based on RFC documentation of the certificate type. The availability based on RFC documentation of the certificate type. The availability
of private types under 0x00FD and 0x00FE should satisfy most of private types under 0x00FD and 0x00FE should satisfy most
requirements for proprietary or private types. requirements for proprietary or private types.
8. Changes since RFC 2538 8. Changes since RFC 2538
1. Editorial changes to conform with new document requirements, 1. Editorial changes to conform with new document requirements,
including splitting reference section into two parts and updating including splitting reference section into two parts and updating
the references to point at latest versions, and to add some the references to point at latest versions, and to add some
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4. Clarify that integers in the representation format are decimal. 4. Clarify that integers in the representation format are decimal.
5. Replace KEY/SIG with DNSKEY/RRSIG etc, to align with DNSSECbis 5. Replace KEY/SIG with DNSKEY/RRSIG etc, to align with DNSSECbis
terminology. Improve reference for Key Tag Algorithm terminology. Improve reference for Key Tag Algorithm
calculations. calculations.
6. Add examples that suggest use of CNAME to reduce bandwidth. 6. Add examples that suggest use of CNAME to reduce bandwidth.
7. In section 3, appended the last paragraphs that discuss 7. In section 3, appended the last paragraphs that discuss
"content-based" vs "purpose-based" owner names. Add section 3.2 "content-based" vs "purpose-based" owner names. Add section 3.2
for purpose-based X.509 CERT owner names, and section 3.4 for for purpose-based X.509 CERT owner names, and section 3.4 for
purpose-based OpenPGP CERT owner names. purpose-based OpenPGP CERT owner names.
8. Added size considerations. 8. Added size considerations.
9. Added indirect types IPKIX, ISPKI, and IPGP.
9. References 9. References
9.1 Normative References 9.1 Normative References
[1] Mockapetris, P., "Domain names - concepts and facilities", STD [1] Mockapetris, P., "Domain names - concepts and facilities", STD
13, RFC 1034, November 1987. 13, RFC 1034, November 1987.
[2] Mockapetris, P., "Domain names - implementation and [2] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987. specification", STD 13, RFC 1035, November 1987.
skipping to change at page 12, line 22 skipping to change at page 12, line 40
2004. 2004.
9.2 Informative References 9.2 Informative References
[10] Bradner, S., "Key words for use in RFCs to Indicate Requirement [10] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
[11] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings", [11] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings",
RFC 3548, July 2003. RFC 3548, July 2003.
[12] Richardson, M., "A method for storing IPsec keying material in
DNS", draft-ietf-ipseckey-rr-11 (work in progress), July 2004.
Author's Address Author's Address
Simon Josefsson Simon Josefsson
EMail: [email protected] EMail: [email protected]
Appendix A. Copying conditions Appendix A. Copying conditions
Regarding the portion of this document that was written by Simon Regarding the portion of this document that was written by Simon
Josefsson ("the author", for the remainder of this section), the Josefsson ("the author", for the remainder of this section), the
 End of changes. 

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