< draft-polk-ecrit-dhc-lost-discovery-00.txt		draft-polk-ecrit-dhc-lost-discovery-01.txt >
	Network Working Group H. Schulzrinne		Network Working Group H. Schulzrinne
	Internet-Draft Columbia U.		Internet-Draft Columbia U.
	Intended status: Standards Track J. Polk		Intended status: Standards Track J. Polk
	Expires: March 4, 2007 Cisco		Expires: March 31, 2007 Cisco
	H. Tschofenig		H. Tschofenig
	Siemens		Siemens
	August 31, 2006		September 27, 2006
	A Dynamic Host Configuration Protocol (DHCP) based Location-to-Service		A Dynamic Host Configuration Protocol (DHCP) based Location-to-Service
	Translation Protocol (LoST) Discovery Procedure		Translation Protocol (LoST) Discovery Procedure
	draft-polk-ecrit-dhc-lost-discovery-00.txt		draft-polk-ecrit-dhc-lost-discovery-01.txt
	Status of this Memo		Status of this Memo
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	applicable patent or other IPR claims of which he or she is aware		applicable patent or other IPR claims of which he or she is aware
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	Copyright Notice		Copyright Notice
	Copyright (C) The Internet Society (2006).		Copyright (C) The Internet Society (2006).
	Abstract		Abstract
	The Location-to-Service Translation Protocol (LoST) describes an XML-		The Location-to-Service Translation Protocol (LoST) describes an XML-
	based protocol for mapping service identifiers and geospatial or		based protocol for mapping service identifiers and geospatial or
	civic location information to service contact Uniform Resource		civic location information to service contact Uniform Resource
	skipping to change at page 2, line 21 ¶		skipping to change at page 2, line 14 ¶
	placement closer to the end host, e.g., in the access network, is		placement closer to the end host, e.g., in the access network, is
	desireable. Such a LoST server placement provides benefits in		desireable. Such a LoST server placement provides benefits in
	disaster situations with intermittent network connectivity regarding		disaster situations with intermittent network connectivity regarding
	the resiliency of emergency service communication.		the resiliency of emergency service communication.
	This document describes how a LoST client can discover a LoST server		This document describes how a LoST client can discover a LoST server
	using the Dynamic Host Configuration Protocol (DHCP).		using the Dynamic Host Configuration Protocol (DHCP).
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4		2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3
	3. LoST Server DHCPv4 Option . . . . . . . . . . . . . . . . . . 5		3. Domain Name Encoding . . . . . . . . . . . . . . . . . . . . . 3
	3.1. LoST Servers Domain Name List . . . . . . . . . . . . . . 5		4. LoST Server DHCPv4 Option . . . . . . . . . . . . . . . . . . . 4
	3.2. LoST Servers IPv4 Address List . . . . . . . . . . . . . . 6		5. LoST Server DHCPv6 Option . . . . . . . . . . . . . . . . . . . 4
	4. LoST Server DHCPv6 Option . . . . . . . . . . . . . . . . . . 8		6. Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
	4.1. LoST Servers Domain Name List . . . . . . . . . . . . . . 8		7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5
	4.2. LoST Servers IPv6 Address List . . . . . . . . . . . . . . 9		7.1. IANA Consideration for DHCPv4 Option . . . . . . . . . . . 6
	4.3. Client Operation . . . . . . . . . . . . . . . . . . . . . 10		7.2. IANA Consideration for DHCPv6 Option . . . . . . . . . . . 6
	4.4. Server Operation . . . . . . . . . . . . . . . . . . . . . 10		8. Security Considerations . . . . . . . . . . . . . . . . . . . . 6
	5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11		9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 6
	6. Security Considerations . . . . . . . . . . . . . . . . . . . 12		10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6
	7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13		10.1. Normative References . . . . . . . . . . . . . . . . . . . 6
	8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14		10.2. Informative References . . . . . . . . . . . . . . . . . . 7
	8.1. Normative References . . . . . . . . . . . . . . . . . . . 14		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8
	8.2. Informative References . . . . . . . . . . . . . . . . . . 14		Intellectual Property and Copyright Statements . . . . . . . . . . 9
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
	Intellectual Property and Copyright Statements . . . . . . . . . . 17
	1. Introduction		1. Introduction
	The Location-to-Service Translation Protocol (LoST)		The Location-to-Service Translation Protocol (LoST)
	[I-D.ietf-ecrit-lost] describes an XML-based protocol for mapping		[I-D.ietf-ecrit-lost] describes an XML-based protocol for mapping
	service identifiers and geospatial or civic location information to		service identifiers and geospatial or civic location information to
	service contact Uniform Resource Locators (URLs).		service contact Uniform Resource Locators (URLs).
	In order to query the LoST server, the LoST client needs to know its		In order to interact with a LoST server, the LoST client finally
	address. Several mechanisms can be used to learn this address,		needs to know its IP address. Several mechanisms can be used to
	including manual configuration. In some environments where DHCP is		learn this address, including manual configuration. In environments
	used and the local access networks either deploys a LoST server or		where the access network itself either deploys a LoST server or knows
	knows the address or host name of a third party provided LoST server,		a third party that operates a LoST server DHCP can provide the end
	DHCP can provide the end host with this information.		host with a domain name. This domain name is then used as input to
			the DNS-based resolution mechanism described in LoST
			[I-D.ietf-ecrit-lost] that reuses the URI-enabled NAPTR specification
			(see [I-D.daigle-unaptr]).
	This document specifies a DHCPv4 and a DHCPv6 option that allows LoST		This document specifies a DHCPv4 and a DHCPv6 option that allows LoST
	clients to discover local LoST servers.		clients to discover local LoST servers.
	Section 2 provides terminology. Section 3 describes the DHCPv4		Section 2 provides terminology. Section 4 describes the DHCPv4
	option while Section 4 describes the DHCPv6 option, with the same		option while Section 5 describes the DHCPv6 option, with the same
	functionality. IANA and Security Considerations complete the		functionality. IANA and Security Considerations complete the
	document in Section 5 and Section 6.		document in Section 7 and Section 8.
	2. Terminology		2. Terminology
	In this document, the key words "MUST", "MUST NOT", "REQUIRED",		In this document, the key words "MUST", "MUST NOT", "REQUIRED",
	"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",		"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
	and "OPTIONAL" are to be interpreted as described in RFC 2119		and "OPTIONAL" are to be interpreted as described in RFC 2119
	[RFC2119].		[RFC2119].
	Within this document, we use terminology from		Within this document, we use terminology from
	[I-D.ietf-ecrit-requirements] and [I-D.ietf-ecrit-lost].		[I-D.ietf-ecrit-requirements] and [I-D.ietf-ecrit-lost].
	3. LoST Server DHCPv4 Option		3. Domain Name Encoding
	The LoST server DHCP option carries either a 32-bit (binary) IPv4
	address or, preferably, a DNS (RFC 1035 [RFC1035]) fully-qualified
	domain name to be used by the LoST client to locate a LoST server.
	This option has two encodings, specified by the encoding byte ('enc')
	that follows the code byte. If the encoding byte has the value 0, it
	is followed by a list of domain names. If the encoding byte has the
	value 1, it is followed by one or more IPv4 addresses (Section 3.2).
	All implementations MUST support both encodings. The 'Len' field
	indicates the total number of octets in the option following the
	'Len' field, including the encoding byte.
	A DHCP server MUST NOT mix the two encodings in the same DHCP
	message, even if it sends two different instances of the same option.
	Attempts to do so would result in incorrect client behavior as DHCP
	processing rules call for the concatenation of multiple instances of
	an option into a single option prior to processing the option
	[RFC3396].
	The code for this option is TBD.
	3.1. LoST Servers Domain Name List
	If the 'enc' byte has a value of 0, the encoding byte is followed by		This section describes the encoding of the domain name used in the
	a sequence of labels, encoded according to Section 3.1 of RFC 1035		DHCPv4 option shown in Section 4 and also used in the DHCPv6 option
	[RFC1035], quoted below:		shown in Section 5.
	Domain names in messages are expressed in terms of a sequence of		The domain name is encoded according to Section 3.1 of RFC 1035
	labels. Each label is represented as a one octet length field		[RFC1035] whereby each label is represented as a one octet length
	followed by that number of octets. Since every domain name ends with		field followed by that number of octets. The domain name ends with
	the null label of the root, a domain name is terminated by a length		the null label of the root, a domain name is terminated by a length
	byte of zero. The high order two bits of every length octet must be		byte of zero. The high order two bits of every length octet must be
	zero, and the remaining six bits of the length field limit the label		zero, and the remaining six bits of the length field limit the label
	to 63 octets or less. To simplify implementations, the total length		to 63 octets or less. To simplify implementations, the total length
	of a domain name (i.e., label octets and label length octets) is		of a domain name (i.e., label octets and label length octets) is
	restricted to 255 octets or less.		restricted to 255 octets or less.
	RFC 1035 [RFC1035] encoding was chosen to accommodate future		RFC 1035 [RFC1035] encoding was chosen to accommodate future
	internationalized domain name mechanisms.		internationalized domain name mechanisms.
	The minimum length for this encoding is 3.		For DHCPv4 only: If the length of the domain name exceeds the
			maximum permissible within a single option (i.e., 254 octets), then
	The option MAY contain multiple domain names, but these SHOULD refer		the domain name MUST be represented in the DHCP message as specified
	to different NAPTR records, rather than different A records. The		in [RFC3396].
	client MUST try the records in the order listed. The client only
	resolves the subsequent domain names if attempts to contact the first
	one failed or yielded no common transport protocols between client
	and server or denote a domain administratively prohibited by client
	policy.
	Use of multiple domain names is not meant to replace NAPTR (?TBD?)
	and SRV records, but rather to allow a single DHCP server to indicate
	LoST servers operated by multiple providers.
	Clients MUST support compression according to the encoding in Section
	4.1.4 ("Domain Names - Implementation And Specification") of
	[RFC1035].
	Since the domain names are supposed to be different domains,		4. LoST Server DHCPv4 Option
	compression will likely have little effect, however.
	If the length of the domain list exceeds the maximum permissible		The LoST server DHCPv4 option carries a DNS (RFC 1035 [RFC1035])
	within a single option (254 octets), then the domain list MUST be		fully-qualified domain name to be used by the LoST client to locate a
	represented in the DHCP message as specified in [RFC3396].		LoST server.
	The DHCP option for this encoding has the following format:		The DHCP option for this encoding has the following format:
	Code Len enc DNS name of LoST server		Code Len LoST Server Domain Name
	+-----+-----+-----+-----+-----+-----+-----+-----+--		+-----+-----+-----+-----+-----+-----+-----+----
	| TBD | n | 0 | s1 | s2 | s3 | s4 | s5 | ...		| TBD | n | s1 | s2 | s3 | s4 | s5 | ...
	+-----+-----+-----+-----+-----+-----+-----+-----+--		+-----+-----+-----+-----+-----+-----+-----+----
	Figure 1: LoST FQDN DHCPv4 Option		Figure 1: LoST FQDN DHCPv4 Option
	As an example, consider the case where the server wants to offer two		Code: OPTION_LOST (TBD1)
	LoST servers, "example.com" and "example.net". These would be
	encoded as follows:
	+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
	|TBD|27 | 0 | 7 |'e'|'x'|'a'|'m'|'p'|'l'|'e'| 3 |'c'|'o'|'m'| 0 |
	+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
	+---+---+---+---+---+---+---+---+---+---+---+---+---+
	| 7 |'e'|'x'|'a'|'m'|'p'|'l'|'e'| 3 |'n'|'e'|'t'| 0 |
	+---+---+---+---+---+---+---+---+---+---+---+---+---+
	Figure 2: Example for a LoST FQDN DHCPv4 Option
	3.2. LoST Servers IPv4 Address List
	If the 'enc' byte has a value of 1, the encoding byte is followed by
	a list of IPv4 addresses indicating LoST servers available to the
	client. Servers MUST be listed in order of preference.
	Its minimum length is 5, and the length MUST be a multiple of 4 plus
	one. The offset is measured from the beginning of the option.
	The DHCP option for this encoding has the following format:
	Code Len enc Address 1 Address 2
	+-----+-----+-----+-----+-----+-----+-----+-----+--
	| TBD | n | 1 | a1 | a2 | a3 | a4 | a1 | ...
	+-----+-----+-----+-----+-----+-----+-----+-----+--
	Figure 3: LoST IP Address(es) DHCPv4 Option
	4. LoST Server DHCPv6 Option
	This document defines two DHCPv6 options that describe a local LoST
	server: one carries a list of domain names (see Section 4.1), the
	other a list of 128-bit (binary) IPv6 addresses (see Section 4.2).
	Since DHCPv6 does not suffer from a shortage of option codes, we
	avoid the encoding byte found in the IPv4 DHCP option for LoST
	servers (see Section 3). This makes the option shorter, easier to
	parse, simplifies appropriate word alignment for the numeric
	addresses and allows the client to request either numeric or
	domain name options using the "option request option".
	An implementation implementing this specification MUST support both
	options described in Section 4.1 and in Section 4.2.
	4.1. LoST Servers Domain Name List		Len: Length of the 'LoST Server Domain Name' field
			in octets; variable.
	The option length is followed by a sequence of labels, encoded		LoST server Domain Name: The domain name of the LoST
	according to Section 3.1 of RFC 1035 [RFC1035], quoted below:		server for the client to use.
	"Domain names in messages are expressed in terms of a sequence of		The encoding of the domain name is described in Section 3.
	labels. Each label is represented as a one octet length field
	followed by that number of octets. Since every domain name ends
	with the null label of the root, a domain name is terminated by a
	length byte of zero. The high order two bits of every length
	octet must be zero, and the remaining six bits of the length field
	limit the label to 63 octets or less. To simplify
	implementations, the total length of a domain name (i.e., label
	octets and label length octets) is restricted to 255 octets or
	less."
	RFC 1035 [RFC1035] encoding was chosen to accommodate future		Only a single domain name MUST be present in the DHCPv4 option.
	internationalized domain name mechanisms.
	The option MAY contain multiple domain names, but these SHOULD refer		5. LoST Server DHCPv6 Option
	to different NAPTR records, rather than different A records. The
	client MUST try the records in the order listed. The client only
	resolves the subsequent domain names if attempts to contact the first
	one failed or yielded no common transport protocols between client
	and server or denote a domain administratively prohibited by client
	policy. Domain names MUST be listed in order of preference.
	Use of multiple domain names is not meant to replace NAPTR or SRV		This document defines a DHCPv6 options to carry a domain name.
	records, but rather to allow a single DHCP server to indicate LoST
	servers operated by multiple providers.
	The DHCPv6 option has the format shown in Figure 4.		The DHCPv6 option has the format shown in Figure 3.
	0 1 2 3		0 1 2 3
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1		0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| OPTION_LOST_SERVER_D | option-length |		| OPTION_LOST | option-length |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| LoST Server Domain Name List |		| LoST Server Domain Name |
	| ... |		| ... |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+		+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	Figure 4: DHCPv6 Option for LoST Server Domain Name List		Figure 3: DHCPv6 Option for LoST Server Domain Name List
	option-code: OPTION_LOST_SERVER_D (TBD)		option-code: OPTION_LOST (TBD2)
	option-length: Length of the 'LoST Server Domain Name List' field		option-length: Length of the 'LoST Server Domain Name' field
	in octets; variable.		in octets; variable.
	LoST server Domain Name List: The domain names of LoST		LoST server Domain Name: The domain name of the LoST
	servers for the client to use. The domain names are encoded		server for the client to use.
	as specified in Section 8 ("Representation and use of domain
	names") of the DHCPv6 specification [RFC3315].
	4.2. LoST Servers IPv6 Address List
	This option specifies a list of IPv6 addresses indicating LoST
	servers available to the client. Servers MUST be listed in order of
	preference.
	The DHCPv6 option has the format shown in Figure 6.
	0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| OPTION_LOST_SERVER_A | option-len |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| |
	| LoST server (IP address) |
	| |
	| |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| |
	| LoST server (IP address) |
	| |
	| |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	| ... |
	+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	Figure 6: DHCPv6 Option for LoST Server IPv6 Address List
	option-code: OPTION_LOST_SERVER_A (TBD)
	option-length: Length of the 'options' field in octets; must be a
	multiple of 16.
	LoST server: IPv6 address of a LoST server for the client to use.
	The servers are listed in the order of preference for
	use by the client.
	4.3. Client Operation
	A client may request either or both of the LoST Servers Domain Name
	List and LoST IPv6 Address List options in an Options Request Option
	(ORO) as described in [RFC3315],
	If a client receives both the LoST Servers Domain Name List and LoST		A DHCPv6 client may request a LoST server domain name in an Options
	Servers IPv6 Address List options, it SHOULD use the LoST Servers		Request Option (ORO) as described in [RFC3315].
	Domain Name List option. Only if no server in the LoST Servers
	Domain Name List can be resolved or reached, the client MAY use the
	LoST Servers IPv6 Address List option.
	4.4. Server Operation		The encoding of the domain name is described in Section 3.
	A server MAY send a client one or both of the LoST Servers Domain		Only a single domain name MUST be present in the DHCPv6 option.
	Name List and LoST Servers IPv6 Address List options.
	If a client requests both options and the server is configured for		6. Example
	both, the server MAY send a client only one of these options and
	SHOULD send the LoST Servers Domain Name List.
	A server configured with the LoST Servers IPv6 Address List option		This section shows an example of a DHCPv4 option where the DHCP
	MUST send a client the LoST Servers IPv6 Address List option if that		server wants to offer the "example.com" domain name to the client as
	client requested the LoST Servers IPv6 Address List option and not		input to the U-NAPTR LoST discovery procedure. This domain name
	the LoST Servers Domain Name List option in an ORO (see [RFC3315]).		would be encoded as follows:
	The following table summarizes the server's response:		+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
			|TBD|13 | 7 |'e'|'x'|'a'|'m'|'p'|'l'|'e'| 3 |'c'|'o'|'m'| 0 |
			+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
	Client sends in ORO Domain Name List IPv6 Address List		Figure 5: Example for a LoST FQDN DHCPv4 Option
	__________________________________________________________________
	Neither option SHOULD MAY
	LoST Servers Domain Name List SHOULD MAY
	LoST Servers IPv6 Address List MAY MUST
	Both options SHOULD MAY
	5. IANA Considerations		7. IANA Considerations
			7.1. IANA Consideration for DHCPv4 Option
	The following DHCPv4 option code for the Location-to-Service		The following DHCPv4 option code for the Location-to-Service
	Translation Protocol (LoST) server option must be assigned by IANA:		Translation Protocol (LoST) server option must be assigned by IANA:
	Option Name Value Described in		Option Name Value Described in
	-----------------------------------------------		-----------------------------------------------
	OPTION_LOST TBD Section 3		OPTION_LOST TBD Section 4
			7.2. IANA Consideration for DHCPv6 Option
	IANA is requested to assign the following DHCPv6 option codes for the		IANA is requested to assign the following DHCPv6 option codes for the
	Location-to-Service Translation Protocol (LoST) options:		Location-to-Service Translation Protocol (LoST) options:
	Option Name Value Described in		Option Name Value Described in
	------------------------------------------------		------------------------------------------------
	OPTION_LOST_SERVER_D TBD Section 4.1		OPTION_LOST TBD Section 5
	OPTION_LOST_SERVER_A TBD Section 4.2
	6. Security Considerations		8. Security Considerations
	If an adversary manages to modify the response from a DHCP server or		If an adversary manages to modify the response from a DHCP server or
	insert its own response, a LoST client could be led to contact a		insert its own response, a LoST client could be led to contact a
	rogue LoST server under the control of the adversary or be given an		rogue LoST server under the control of the adversary or be given an
	invalid address. These threats are documented in		invalid address. These threats are documented in
	[I-D.ietf-ecrit-security-threats]. The security considerations in		[I-D.ietf-ecrit-security-threats]. The security considerations in
	[RFC2131], [RFC2132] and [RFC3315] are applicable to this document.		[RFC2131], [RFC2132] and [RFC3315] are applicable to this document.
	7. Acknowledgements		9. Acknowledgements
	This document copies a lot of text from [RFC3361] and from [RFC3319].
	The authors would therefore like to thank Henning Schulzrinne,
	Jonathan Rosenberg and Bernie Volz for their work on these two RFCs.
	Furthermore, the authors would like to thank Christian Dickmann and		The authors would like to thank Andrew Newton and Leslie Daigle for
	Mayutan Arumaithurai for their draft review.		their draft review. We would like to particularly thank Andrew
			Newton for the simplifications he proposed.
	8. References		10. References
	8.1. Normative References		10.1. Normative References
	[I-D.ietf-ecrit-lost]		[I-D.ietf-ecrit-lost]
	Hardie, T., "LoST: A Location-to-Service Translation		Hardie, T., "LoST: A Location-to-Service Translation
	Protocol", draft-ietf-ecrit-lost-00 (work in progress),		Protocol", draft-ietf-ecrit-lost-01 (work in progress),
	June 2006.		September 2006.
	[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.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Requirement Levels", RFC 2119, BCP 14, March 1997.		Requirement Levels", RFC 2119, BCP 14, March 1997.
	[RFC2131] Droms, R., "Dynamic Host Configuration Protocol",		[RFC2131] Droms, R., "Dynamic Host Configuration Protocol",
	RFC 2131, March 1997.		RFC 2131, March 1997.
	[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor		[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor
	Extensions", RFC 2132, March 1997.		Extensions", RFC 2132, March 1997.
	[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,		[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
	and M. Carney, "Dynamic Host Configuration Protocol for		and M. Carney, "Dynamic Host Configuration Protocol for
	IPv6 (DHCPv6)", RFC 3315, July 2003.		IPv6 (DHCPv6)", RFC 3315, July 2003.
	8.2. Informative References		10.2. Informative References
			[I-D.daigle-unaptr]
			Daigle, L., "Domain-based Application Service Location
			Using URIs and the Dynamic Delegation Discovery Service
			(DDDS)", draft-daigle-unaptr-00 (work in progress),
			June 2006.
	[I-D.ietf-ecrit-requirements]		[I-D.ietf-ecrit-requirements]
	Schulzrinne, H. and R. Marshall, "Requirements for		Schulzrinne, H. and R. Marshall, "Requirements for
	Emergency Context Resolution with Internet Technologies",		Emergency Context Resolution with Internet Technologies",
	draft-ietf-ecrit-requirements-12 (work in progress),		draft-ietf-ecrit-requirements-12 (work in progress),
	August 2006.		August 2006.
	[I-D.ietf-ecrit-security-threats]		[I-D.ietf-ecrit-security-threats]
	Taylor, T., "Security Threats and Requirements for		Taylor, T., "Security Threats and Requirements for
	Emergency Call Marking and Mapping",		Emergency Call Marking and Mapping",
End of changes. 46 change blocks.
	248 lines changed or deleted		103 lines changed or added
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