draft-josefsson-dns-url-11.txt		draft-josefsson-dns-url-12.txt
	Network Working Group S. Josefsson		Network Working Group S. Josefsson
	Expires: August 11, 2005		Expires: November 26, 2005
	Domain Name System Uniform Resource Identifiers		Domain Name System Uniform Resource Identifiers
	draft-josefsson-dns-url-11		draft-josefsson-dns-url-12
	Status of this Memo		Status of this Memo
	This document is an Internet-Draft and is subject to all provisions		By submitting this Internet-Draft, each author represents that any
	of section 3 of RFC 3667. By submitting this Internet-Draft, each		applicable patent or other IPR claims of which he or she is aware
	author represents that any applicable patent or other IPR claims of		have been or will be disclosed, and any of which he or she becomes
	which he or she is aware have been or will be disclosed, and any of		aware will be disclosed, in accordance with Section 6 of BCP 79.
	which he or she become aware will be disclosed, in accordance with
	RFC 3668.
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	This Internet-Draft will expire on August 11, 2005.		This Internet-Draft will expire on November 26, 2005.
	Copyright Notice		Copyright Notice
	Copyright (C) The Internet Society (2005).		Copyright (C) The Internet Society (2005).
	Abstract		Abstract
	This document define Uniform Resource Identifiers for Domain Name		This document define Uniform Resource Identifiers for Domain Name
	System resources.		System resources.
			See <http://josefsson.org/dns-url/> for more information.
	Table of Contents		Table of Contents
	1. Introduction and Background . . . . . . . . . . . . . . . . . 3		1. Introduction and Background . . . . . . . . . . . . . . . . . 3
	2. Usage Model . . . . . . . . . . . . . . . . . . . . . . . . . 4		2. Usage Model . . . . . . . . . . . . . . . . . . . . . . . . . 4
	3. DNS URI Registration . . . . . . . . . . . . . . . . . . . . . 5		3. DNS URI Registration . . . . . . . . . . . . . . . . . . . . . 5
	4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 8		4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9		5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9
	6. Security Considerations . . . . . . . . . . . . . . . . . . . 9		6. Security Considerations . . . . . . . . . . . . . . . . . . . 9
	7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9		7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
	8. Copying conditions . . . . . . . . . . . . . . . . . . . . . . 10		8. Copying conditions . . . . . . . . . . . . . . . . . . . . . . 10
	9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10		9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10
	9.1 Normative References . . . . . . . . . . . . . . . . . . . . 10		9.1 Normative References . . . . . . . . . . . . . . . . . . . 10
	9.2 Informative References . . . . . . . . . . . . . . . . . . . 10		9.2 Informative References . . . . . . . . . . . . . . . . . . 10
	Author's Address . . . . . . . . . . . . . . . . . . . . . . . 11		Author's Address . . . . . . . . . . . . . . . . . . . . . . . 11
	A. Revision Changes . . . . . . . . . . . . . . . . . . . . . . . 11		A. Revision Changes . . . . . . . . . . . . . . . . . . . . . . . 11
	A.1 Changes since -06 . . . . . . . . . . . . . . . . . . . . 11		A.1 Changes since -06 . . . . . . . . . . . . . . . . . . . . 11
	A.2 Changes since -07 . . . . . . . . . . . . . . . . . . . . 11		A.2 Changes since -07 . . . . . . . . . . . . . . . . . . . . 12
	A.3 Changes since -08 . . . . . . . . . . . . . . . . . . . . 12		A.3 Changes since -08 . . . . . . . . . . . . . . . . . . . . 12
	A.4 Changes since -09 . . . . . . . . . . . . . . . . . . . . 12		A.4 Changes since -09 . . . . . . . . . . . . . . . . . . . . 12
	A.5 Changes since -10 . . . . . . . . . . . . . . . . . . . . 12		A.5 Changes since -10 . . . . . . . . . . . . . . . . . . . . 12
			A.6 Changes since -11 . . . . . . . . . . . . . . . . . . . . 12
	Intellectual Property and Copyright Statements . . . . . . . . 13		Intellectual Property and Copyright Statements . . . . . . . . 13
	1. Introduction and Background		1. Introduction and Background
	The Domain Name System (DNS) [1][2] is a widely deployed system used		The Domain Name System (DNS) [1][2] is a widely deployed system used
	to, among other things, translate host names into IP addresses.		to, among other things, translate host names into IP addresses.
	Recent work has added support for storing certificates and		Recent work has added support for storing certificates and
	certificate revocation lists (CRLs) in the DNS [9]. Several		certificate revocation lists (CRLs) in the DNS [9]. Several
	protocols use Uniform Resource Locators (URLs) to point at		protocols use Uniform Resource Locators (URLs) to point at
	certificates and CRLs. By defining a Uniform Resource Identifier		certificates and CRLs. By defining a Uniform Resource Identifier
	(URI) scheme for DNS resources, such protocols can reference		(URI) scheme for DNS resources, such protocols can reference
	certificates and CRLs stored in the DNS.		certificates and CRLs stored in the DNS.
	A few examples of protocols that may utilize DNS URIs:		Two examples of data structures that may embed DNS URIs:
	o The OpenPGP Message Format [7], where an end-user may indicate the		o The OpenPGP Message Format [7], where an end-user may indicate the
	location of a copy of any updates to her key, using the "preferred		location of a copy of any updates to her key, using the "preferred
	key server" field.		key server" field.
	o The X.509 Online Certificate Status Protocol [10], where the OCSP		o The Internet X.509 Public Key Infrastructure [14] format, where
	responder can indicate where a CRL is found, using the		the issuer may use a DNS URI in a CRL Distribution Point
	id-pkix-ocsp-crl extension.		certificate extension field.
	The DNS URI scheme defined here can be used to reference any data		The DNS URI scheme defined here can be used to reference any data
	stored in the DNS, and is not limited to certificates or CRLs. The		stored in the DNS, and is not limited to certificates or CRLs. The
	purpose of this specification is to define a generic DNS URI, not to		purpose of this specification is to define a generic DNS URI, not to
	specify a solution only for certificates stored in the DNS.		specify a solution only for certificates stored in the DNS.
	Data browsers may support DNS URIs by forming DNS queries and render		Data browsers may support DNS URIs by forming DNS queries and render
	DNS responses using HTML [13], similar to what is commonly done for		DNS responses using HTML [13], similar to what is commonly done for
	FTP [5] resources.		FTP [6] resources.
	The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",		The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this		"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	document are to be interpreted as described in RFC 2119 [6].		document are to be interpreted as described in RFC 2119 [3].
	2. Usage Model		2. Usage Model
	The reader is referred to section 1 of [4] for an in-depth discussion		The reader is referred to section 1 of [5] for an in-depth discussion
	of URI classifications. In particular, the reader is assumed to be		of URI classifications. In particular, the reader is assumed to be
	familiar with the "name" vs "locator" distinction. This section		familiar with the "name" vs "locator" distinction. This section
	describe how the DNS URI scheme is intended to be used, and outline		describe how the DNS URI scheme is intended to be used, and outline
	future work that may be required to use URIs with the DNS for some		future work that may be required to use URIs with the DNS for some
	applications.		applications.
	The URI scheme described in this document focus on the data stored in		The URI scheme described in this document focus on the data stored in
	the DNS. As such, there is no provision to specify any of the fields		the DNS. As such, there is no provision to specify any of the fields
	in the actual DNS protocol. This is intentional, so that the URI may		in the actual DNS protocol. This is intentional, so that the URI may
	be used even in situations where the DNS protocol is not used		be used even in situations where the DNS protocol is not used
	skipping to change at page 5, line 14		skipping to change at page 5, line 14
	3. DNS URI Registration		3. DNS URI Registration
	The section contain the registration template for the DNS URI scheme		The section contain the registration template for the DNS URI scheme
	in accordance with [12].		in accordance with [12].
	URL scheme name: "dns".		URL scheme name: "dns".
	URL scheme syntax: A DNS URI designate a DNS resource record set,		URL scheme syntax: A DNS URI designate a DNS resource record set,
	referenced by domain name, class, type and optionally the authority.		referenced by domain name, class, type and optionally the authority.
	The DNS URI follows the generic syntax from RFC 3986 [4], and is		The DNS URI follows the generic syntax from RFC 3986 [5], and is
	described using ABNF [3]. Strings are not case sensitive and free		described using ABNF [4]. Strings are not case sensitive and free
	insertion of linear-white-space is not permitted.		insertion of linear-white-space is not permitted.
	dnsurl = "dns:" [ "//" dnsauthority "/" ]		dnsurl = "dns:" [ "//" dnsauthority "/" ]
	dnsname ["?" dnsquery]		dnsname ["?" dnsquery]
	dnsauthority = host [ ":" port ]		dnsauthority = host [ ":" port ]
	; See RFC 3986 for the		; See RFC 3986 for the
	; definition of "host" and "port".		; definition of "host" and "port".
	dnsname = *pchar		dnsname = *pchar
	skipping to change at page 5, line 44		skipping to change at page 5, line 44
	; "dnsname" value is to be		; "dnsname" value is to be
	; interpreted as the root itself.		; interpreted as the root itself.
	; See below on relative dnsname's.		; See below on relative dnsname's.
	dnsquery = dnsqueryelement [";" dnsquery]		dnsquery = dnsqueryelement [";" dnsquery]
	dnsqueryelement = ( "CLASS=" dnsclassval ) / ( "TYPE=" dnstypeval )		dnsqueryelement = ( "CLASS=" dnsclassval ) / ( "TYPE=" dnstypeval )
	; Each clause MUST NOT be used more		; Each clause MUST NOT be used more
	; than once.		; than once.
	dnsclassval = 1*digit / "IN" / "CH" / ...		dnsclassval = 1*digit / "IN" / "CH" /
	; Any IANA registered DNS class		<Any IANA registered DNS class mnemonic>
	; expressed as mnemonic or as
	; decimal integer.
	dnstypeval = 1*digit / "A" / "NS" / "MD" / ...		dnstypeval = 1*digit / "A" / "NS" / "MD" /
	; Any IANA registered DNS type		<Any IANA registered DNS type mnemonic>
	; expressed as mnemonic or as
	; decimal integer.
	Unless specified in the URI, the authority ("dnsauthority") is		Unless specified in the URI, the authority ("dnsauthority") is
	assumed to be locally known, the class ("dnsclassval") to be the		assumed to be locally known, the class ("dnsclassval") to be the
	Internet class ("IN"), and the type ("dnstypeval") to be the Address		Internet class ("IN"), and the type ("dnstypeval") to be the Address
	type ("A"). These default values match the typical use of DNS; to		type ("A"). These default values match the typical use of DNS; to
	look up addresses for host names.		look up addresses for host names.
	A dnsquery element MUST NOT contain more than one occurance of the		A dnsquery element MUST NOT contain more than one occurance of the
	"CLASS" and "TYPE" fields. For example, both		"CLASS" and "TYPE" fields. For example, both "dns:
	"dns:example?TYPE=A;TYPE=TXT" and "dns:example?TYPE=A;TYPE=A" are		example?TYPE=A;TYPE=TXT" and "dns:example?TYPE=A;TYPE=A" are invalid.
	invalid. However, the fields may occur in any order, so that both		However, the fields may occur in any order, so that both "dns:
	"dns:example?TYPE=A;CLASS=IN" and "dns:example?CLASS=IN;TYPE=A" are		example?TYPE=A;CLASS=IN" and "dns:example?CLASS=IN;TYPE=A" are valid.
	valid.
	The digit representation of types and classes MAY be used when a		The digit representation of types and classes MAY be used when a
	mnemonic for the corresponding value is not well known (e.g., for		mnemonic for the corresponding value is not well known (e.g., for
	newly introduced types or classes), but SHOULD NOT be used for the		newly introduced types or classes), but SHOULD NOT be used for the
	types or classes defined in the DNS specification [2]. All		types or classes defined in the DNS specification [2]. All
	implementations MUST recognize the mnemonics defined in [2].		implementations MUST recognize the mnemonics defined in [2].
	To avoid ambiguity, relative "dnsname" values (i.e., those not ending		To avoid ambiguity, relative "dnsname" values (i.e., those not ending
	with ".") are assumed to be relative to the root. For example,		with ".") are assumed to be relative to the root. For example, "dns:
	"dns:host.example" and "dns:host.example." both refer to the same		host.example" and "dns:host.example." both refer to the same owner
	owner name, namely "host.example.". Further, an empty "dnsname"		name, namely "host.example.". Further, an empty "dnsname" value is
	value is considered to be a degenerative form of a relative name,		considered to be a degenerative form of a relative name, which refer
	which refer to the root (".").		to the root (".").
	To resolve a DNS URI using the DNS protocol [2] a query is created,		To resolve a DNS URI using the DNS protocol [2] a query is created,
	using as input the dnsname, dnsclassval and dnstypeval from the URI		using as input the dnsname, dnsclassval and dnstypeval from the URI
	string (or the appropriate default values). If an authority		string (or the appropriate default values). If an authority
	("dnsauthority") is given in the URI string, this indicate the server		("dnsauthority") is given in the URI string, this indicate the server
	that should receive the DNS query, otherwise the default DNS server		that should receive the DNS query, otherwise the default DNS server
	should receive it.		should receive it.
	Note that DNS URIs could be resolved by other protocols than the DNS		Note that DNS URIs could be resolved by other protocols than the DNS
	protocol, or by using the DNS protocol in some other way than as		protocol, or by using the DNS protocol in some other way than as
	skipping to change at page 6, line 52		skipping to change at page 6, line 47
	usage. The previous paragraph only illustrate how DNS URIs are		usage. The previous paragraph only illustrate how DNS URIs are
	resolved using the DNS protocol.		resolved using the DNS protocol.
	A client MAY want to check that it understands the dnsclassval and		A client MAY want to check that it understands the dnsclassval and
	dnstypeval before sending a query, so that it will be able to		dnstypeval before sending a query, so that it will be able to
	understand the response. However, a typical example of a client that		understand the response. However, a typical example of a client that
	would not need to check dnsclassval and dnstypeval would be a proxy,		would not need to check dnsclassval and dnstypeval would be a proxy,
	that would just treat the received answer as opaque data.		that would just treat the received answer as opaque data.
	Character encoding considerations: The characters are encoded as per		Character encoding considerations: The characters are encoded as per
	RFC 3986 [4]. The DNS protocol do not consider character sets, it		RFC 3986 [5]. The DNS protocol do not consider character sets, it
	simply transports opaque data. In particular, the "dnsname" field of		simply transports opaque data. In particular, the "dnsname" field of
	the DNS URI is to be considered an internationalized domain name		the DNS URI is to be considered an internationalized domain name
	(IDN) unaware domain name slot, in the terminology of [15]. The		(IDN) unaware domain name slot, in the terminology of [16]. The
	considerations for "host" and "port" are discussed in [4]		considerations for "host" and "port" are discussed in [5]
	Because "." is used as the DNS label separator, an escaping mechanism		Because "." is used as the DNS label separator, an escaping mechanism
	is required to encode a "." that is part of a DNS label. The		is required to encode a "." that is part of a DNS label. The
	escaping mechanism is described in section 5.1 of RFC 1035. For		escaping mechanism is described in section 5.1 of RFC 1035. For
	example, a DNS label of "exa.mple" can be escaped as "exa\.mple" or		example, a DNS label of "exa.mple" can be escaped as "exa\.mple" or
	"exa\046mple". However, the URI specification disallow the "\"		"exa\046mple". However, the URI specification disallow the "\"
	character from occuring directly in URIs, so it must be escaped as		character from occuring directly in URIs, so it must be escaped as
	"%5c". The single DNS label "exa.mple" is thus encoded as		"%5c". The single DNS label "exa.mple" is thus encoded as "exa%
	"exa%5c.mple". The same mechanism can be used to encode other		5c.mple". The same mechanism can be used to encode other characters,
	characters, for example "?" and ";". Note that "." and "%2e" are		for example "?" and ";". Note that "." and "%2e" are equivalent
	equivalent within dnsname, and are interchangable.		within dnsname, and are interchangable.
	This URI specification allows all possible domain names to be encoded		This URI specification allows all possible domain names to be encoded
	(of course following the encoding rules of [4]), however certain		(of course following the encoding rules of [5]), however certain
	applications may restrict the set of valid characters. Care should		applications may restrict the set of valid characters. Care should
	be taken so that invalid characters in these contexts does not cause		be taken so that invalid characters in these contexts does not cause
	harm. In particular, host names in the DNS have certain		harm. In particular, host names in the DNS have certain
	restrictions. It is up to these application to limit this subset,		restrictions. It is up to these application to limit this subset,
	this URI scheme places no restrictions.		this URI scheme places no restrictions.
	Intended usage: Whenever DNS resources are useful to reference by		Intended usage: Whenever DNS resources are useful to reference by
	protocol independent identifiers, often when the data is more		protocol independent identifiers, often when the data is more
	important than the access method. Since software in general has		important than the access method. Since software in general has
	coped without this so far, it is not anticipated to be implemented		coped without this so far, it is not anticipated to be implemented
	skipping to change at page 8, line 42		skipping to change at page 8, line 37
	The following illustrate a URI for a resource with the name		The following illustrate a URI for a resource with the name
	"ftp.example.org", in the Internet (IN) class and the address (A)		"ftp.example.org", in the Internet (IN) class and the address (A)
	type, but from the DNS authority 192.168.1.1 instead of the default		type, but from the DNS authority 192.168.1.1 instead of the default
	authority:		authority:
	dns://192.168.1.1/ftp.example.org?type=A		dns://192.168.1.1/ftp.example.org?type=A
	The following illustrate various escaping techniques. The owner name		The following illustrate various escaping techniques. The owner name
	would be "world wide web.example\.domain.org" where "\." denote the		would be "world wide web.example\.domain.org" where "\." denote the
	character "." as part of a label, and "." denote the label		character "." as part of a label, and "." denote the label separator:
	separator:
	dns:world%20wide%20web.example%5c.domain.example?TYPE=TXT		dns:world%20wide%20web.example%5c.domain.example?TYPE=TXT
	The following illustrate a strange, but valid, DNS resource:		The following illustrate a strange, but valid, DNS resource:
	dns://fw.example.org/*.%20%00.example?type=TXT		dns://fw.example.org/*.%20%00.example?type=TXT
	5. Acknowledgments		5. Acknowledgments
	Thanks to Stuart Cheshire, Donald Eastlake, Pasi Eronen, Ted Hardie,		Thanks to Stuart Cheshire, Donald Eastlake, Pasi Eronen, Bill Fenner,
	Peter Koch, Andrew Main, Larry Masinter, Michael Mealling, Steve		Ted Hardie, Russ Housley, Peter Koch, Andrew Main, Larry Masinter,
	Mattson, and Paul Vixie for comments and suggestions. The author		Michael Mealling, Steve Mattson, Paul Vixie, Sam Weiler, and Bert
	acknowledges the RSA Laboratories for supporting the work that led to		Wijnen for comments and suggestions. The author acknowledges the RSA
	this document.		Laboratories for supporting the work that led to this document.
	6. Security Considerations		6. Security Considerations
	If a DNS URI references domains in the Internet DNS environment, both		If a DNS URI references domains in the Internet DNS environment, both
	the URI itself and the information referenced by the URI is public		the URI itself and the information referenced by the URI is public
	information. If a DNS URI is used within an "internal" DNS		information. If a DNS URI is used within an "internal" DNS
	environment, both the DNS URI and the data is referenced should be		environment, both the DNS URI and the data is referenced should be
	handled using the same considerations that apply to DNS data in the		handled using the same considerations that apply to DNS data in the
	environment.		environment.
	If information referenced by DNS URIs are used to make security		If information referenced by DNS URIs are used to make security
	decisions (examples of such data include, but is not limited to,		decisions (examples of such data include, but is not limited to,
	certificates stored in the DNS), implementations may need to employ		certificates stored in the DNS), implementations may need to employ
	security techniques such as Secure DNS [8], or even CMS [14] or		security techniques such as Secure DNS [8], or even CMS [15] or
	OpenPGP [7], to protect the data during transport. How to implement		OpenPGP [7], to protect the data during transport. How to implement
	this will depend on the usage scenario, and it is not up to this URI		this will depend on the usage scenario, and it is not up to this URI
	scheme to define how the data referenced by DNS URIs should be		scheme to define how the data referenced by DNS URIs should be
	protected.		protected.
	If applications accept unknown dnsqueryelement values (e.g., accepts		If applications accept unknown dnsqueryelement values (e.g., accepts
	the URI "dns:www.example.org?secret=value" without knowing what the		the URI "dns:www.example.org?secret=value" without knowing what the
	"secret=value" dnsqueryelement means), a covert channel used to		"secret=value" dnsqueryelement means), a covert channel used to
	"leak" information may be enabled. The implications of covert		"leak" information may be enabled. The implications of covert
	channels should be understood by applications that accepts unknown		channels should be understood by applications that accepts unknown
	dnsqueryelement values.		dnsqueryelement values.
	Slight variations, such as difference between upper and lower case in		Slight variations, such as difference between upper and lower case in
	the dnsname field, can be used as a covert channel to leak		the dnsname field, can be used as a covert channel to leak
	information.		information.
	7. IANA Considerations		7. IANA Considerations
	The IANA is asked to register the DNS URI scheme, using the template		The IANA is asked to register the DNS URI scheme, using the template
	in section 2, in accordance with RFC 2717 [12].		in section 3, in accordance with RFC 2717 [12].
	8. Copying conditions		8. Copying conditions
			Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005 Simon Josefsson
	Regarding this entire document or any portion of it, the author makes		Regarding this entire document or any portion of it, the author makes
	no guarantees and is not responsible for any damage resulting from		no guarantees and is not responsible for any damage resulting from
	its use. The author grants irrevocable permission to anyone to use,		its use. The author grants irrevocable permission to anyone to use,
	modify, and distribute it in any way that does not diminish the		modify, and distribute it in any way that does not diminish the
	rights of anyone else to use, modify, and distribute it, provided		rights of anyone else to use, modify, and distribute it, provided
	that redistributed derivative works do not contain misleading author		that redistributed derivative works do not contain misleading author
	or version information. Derivative works need not be licensed under		or version information. Derivative works need not be licensed under
	similar terms.		similar terms.
	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",
	13, RFC 1034, November 1987.		STD 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.
	[3] Crocker, D. and P. Overell, "Augmented BNF for Syntax		[3] Bradner, S., "Key words for use in RFCs to Indicate Requirement
			Levels", BCP 14, RFC 2119, March 1997.
			[4] Crocker, D. and P. Overell, "Augmented BNF for Syntax
	Specifications: ABNF", RFC 2234, November 1997.		Specifications: ABNF", RFC 2234, November 1997.
	[4] Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform Resource		[5] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
	Identifier (URI): Generic Syntax", STD 66, RFC 3986, January		Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986,
	2005.		January 2005.
	9.2 Informative References		9.2 Informative References
	[5] Postel, J. and J. Reynolds, "File Transfer Protocol", STD 9,		[6] Postel, J. and J. Reynolds, "File Transfer Protocol", STD 9,
	RFC 959, October 1985.		RFC 959, October 1985.
	[6] Bradner, S., "Key words for use in RFCs to Indicate Requirement		[7] Callas, J., Donnerhacke, L., Finney, H., and R. Thayer,
	Levels", BCP 14, RFC 2119, March 1997.		"OpenPGP Message Format", RFC 2440, November 1998.
	[7] Callas, J., Donnerhacke, L., Finney, H. and R. Thayer, "OpenPGP
	Message Format", RFC 2440, November 1998.
	[8] Eastlake, D., "Domain Name System Security Extensions", RFC		[8] Eastlake, D., "Domain Name System Security Extensions",
	2535, March 1999.		RFC 2535, March 1999.
	[9] Eastlake, D. and O. Gudmundsson, "Storing Certificates in the		[9] Eastlake, D. and O. Gudmundsson, "Storing Certificates in the
	Domain Name System (DNS)", RFC 2538, March 1999.		Domain Name System (DNS)", RFC 2538, March 1999.
	[10] Myers, M., Ankney, R., Malpani, A., Galperin, S. and C. Adams,		[10] Myers, M., Ankney, R., Malpani, A., Galperin, S., and C. Adams,
	"X.509 Internet Public Key Infrastructure Online Certificate		"X.509 Internet Public Key Infrastructure Online Certificate
	Status Protocol - OCSP", RFC 2560, June 1999.		Status Protocol - OCSP", RFC 2560, June 1999.
	[11] Crawford, M., "Binary Labels in the Domain Name System", RFC		[11] Crawford, M., "Binary Labels in the Domain Name System",
	2673, August 1999.		RFC 2673, August 1999.
	[12] Petke, R. and I. King, "Registration Procedures for URL Scheme		[12] Petke, R. and I. King, "Registration Procedures for URL Scheme
	Names", BCP 35, RFC 2717, November 1999.		Names", BCP 35, RFC 2717, November 1999.
	[13] Connolly, D. and L. Masinter, "The 'text/html' Media Type", RFC		[13] Connolly, D. and L. Masinter, "The 'text/html' Media Type",
	2854, June 2000.		RFC 2854, June 2000.
	[14] Housley, R., "Cryptographic Message Syntax (CMS)", RFC 3369,		[14] Housley, R., Polk, W., Ford, W., and D. Solo, "Internet X.509
			Public Key Infrastructure Certificate and Certificate
			Revocation List (CRL) Profile", RFC 3280, April 2002.
			[15] Housley, R., "Cryptographic Message Syntax (CMS)", RFC 3369,
	August 2002.		August 2002.
	[15] Faltstrom, P., Hoffman, P. and A. Costello, "Internationalizing		[16] Faltstrom, P., Hoffman, P., and A. Costello,
	Domain Names in Applications (IDNA)", RFC 3490, March 2003.		"Internationalizing Domain Names in Applications (IDNA)",
			RFC 3490, March 2003.
	[16] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD		[17] Yergeau, F., "UTF-8, a transformation format of ISO 10646",
	63, RFC 3629, November 2003.		STD 63, RFC 3629, November 2003.
	Author's Address		Author's Address
	Simon Josefsson		Simon Josefsson
	EMail: simon@josefsson.org		Email: simon@josefsson.org
	Appendix A. Revision Changes		Appendix A. Revision Changes
	Note to RFC editor: Remove this appendix before publication.		Note to RFC editor: Remove this appendix before publication.
	A.1 Changes since -06		A.1 Changes since -06
	The MIME registration templates for text/dns and application/dns was		The MIME registration templates for text/dns and application/dns was
	removed, and will be defined in separate documents.		removed, and will be defined in separate documents.
	skipping to change at page 13, line 5		skipping to change at page 12, line 44
	dnsname field is made a IDN unaware domain name slot. Use standard		dnsname field is made a IDN unaware domain name slot. Use standard
	DNS escaping (i.e, "\." for ".") instead of broken approach that		DNS escaping (i.e, "\." for ".") instead of broken approach that
	violated the URI specification. Improve examples. Add security		violated the URI specification. Improve examples. Add security
	considerations.		considerations.
	A.5 Changes since -10		A.5 Changes since -10
	Add section "Usage Model". Move acknowledgements, as per rfc2223bis.		Add section "Usage Model". Move acknowledgements, as per rfc2223bis.
	Add permissive copying condition. Updates to align with RFC 3986.		Add permissive copying condition. Updates to align with RFC 3986.
			A.6 Changes since -11
			Fix typos. IESG feedback: Move RFC2119 reference to normative
			section. Replace OCSP example with X.509 CRL Distribution Point
			extension. Fix ABNF not to use "...".
	Intellectual Property Statement		Intellectual Property Statement
	The IETF takes no position regarding the validity or scope of any		The IETF takes no position regarding the validity or scope of any
	Intellectual Property Rights or other rights that might be claimed to		Intellectual Property Rights or other rights that might be claimed to
	pertain to the implementation or use of the technology described in		pertain to the implementation or use of the technology described in
	this document or the extent to which any license under such rights		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		might or might not be available; nor does it represent that it has
	made any independent effort to identify any such rights. Information		made any independent effort to identify any such rights. Information
	on the procedures with respect to rights in RFC documents can be		on the procedures with respect to rights in RFC documents can be
	found in BCP 78 and BCP 79.		found in BCP 78 and BCP 79.
End of changes.
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