draft-gregorio-uritemplate-01.txt		draft-gregorio-uritemplate-02.txt
	Network Working Group J. Gregorio, Ed.		Network Working Group J. Gregorio, Ed.
	Internet-Draft		Internet-Draft Google
	Intended status: Standards Track M. Hadley, Ed.		Intended status: Standards Track M. Hadley, Ed.
	Expires: January 10, 2008 Sun Microsystems		Expires: May 29, 2008 Sun Microsystems
	M. Nottingham, Ed.		M. Nottingham, Ed.
	D. Orchard		D. Orchard
	BEA Systems, Inc.		BEA Systems, Inc.
	July 9, 2007		Nov 26, 2007
	URI Template		URI Template
	draft-gregorio-uritemplate-01		draft-gregorio-uritemplate-02
	Status of this Memo		Status of this Memo
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	Copyright Notice		Copyright Notice
	Copyright (C) The IETF Trust (2007).		Copyright (C) The IETF Trust (2007).
	Abstract		Abstract
	URI Templates are strings that can be transformed into URIs after		A URI Template is a compact sequence of characters used for the
	embedded variables are substituted. This document defines the syntax		construction of URIs. This specification defines the URI Template
	and processing of URI Templates.		syntax and the process for expanding a URI Template into a URI, along
			with guidelines and security considerations for the use of URI
			Templates on the Internet. The URI Template syntax allows for the
			construction of strings that are a superset of URIs, allowing an
			implementation to process any URI Template without knowing the
			scheme-specific requirements of every possible resulting URI.
	Editorial Note		Editorial Note
	To provide feedback on this Internet-Draft, join the W3C URI mailing		To provide feedback on this Internet-Draft, join the W3C URI mailing
	list (http://lists.w3.org/Archives/Public/uri/) [1].		list (http://lists.w3.org/Archives/Public/uri/) [1].
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 3		1.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 3
	3. URI Template . . . . . . . . . . . . . . . . . . . . . . . . . 4		1.2. Design Considerations . . . . . . . . . . . . . . . . . . 4
	3.1. Template Variables . . . . . . . . . . . . . . . . . . . . 4		1.3. Notational Conventions . . . . . . . . . . . . . . . . . . 4
	3.2. URI Template Substitution . . . . . . . . . . . . . . . . . 4		2. Characters . . . . . . . . . . . . . . . . . . . . . . . . . . 4
	3.3. Using URI Templates . . . . . . . . . . . . . . . . . . . . 5		3. URI Template . . . . . . . . . . . . . . . . . . . . . . . . . 5
	3.3.1. Examples . . . . . . . . . . . . . . . . . . . . . . . 5		3.1. Variables . . . . . . . . . . . . . . . . . . . . . . . . 5
	4. Security Considerations . . . . . . . . . . . . . . . . . . . . 6		3.2. Template Expansions . . . . . . . . . . . . . . . . . . . 6
	5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6		3.3. URI Template Substitution . . . . . . . . . . . . . . . . 6
	6. Normative References . . . . . . . . . . . . . . . . . . . . . 7		3.3.1. The 'opt' operator . . . . . . . . . . . . . . . . . . 7
	Appendix A. Contributors . . . . . . . . . . . . . . . . . . . . . 7		3.3.2. The 'neg' operator . . . . . . . . . . . . . . . . . . 7
	Appendix B. Revision History . . . . . . . . . . . . . . . . . . . 7		3.3.3. The 'prefix' operator . . . . . . . . . . . . . . . . 7
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7		3.3.4. The 'append' operator . . . . . . . . . . . . . . . . 7
	Intellectual Property and Copyright Statements . . . . . . . . . . 9		3.3.5. The 'join' operator . . . . . . . . . . . . . . . . . 7
			3.3.6. The 'listjoin' operator . . . . . . . . . . . . . . . 7
			3.4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . 8
			4. Security Considerations . . . . . . . . . . . . . . . . . . . 10
			5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
			6. Appendix A - Parsing URI Template Expansions . . . . . . . . . 10
			7. Normative References . . . . . . . . . . . . . . . . . . . . . 11
			Appendix A. Contributors . . . . . . . . . . . . . . . . . . . . 11
			Appendix B. Revision History . . . . . . . . . . . . . . . . . . 12
			Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12
			Intellectual Property and Copyright Statements . . . . . . . . . . 13
	1. Introduction		1. Introduction
	URI Templates are strings that contain embedded variables that are		A URI Template provides a simple and extensible format for URI
	transformed into URIs after embedded variables are substituted.		construction. A URI Template is a string that contains embedded
			expansions, text marked off in matching braces ('{', '}'), that
			denotes a part of the string that is to be substituted by a template
			processor to produce a URI. A URI Template is transformed into a URI
			by substituting the expansions with their calculated value.
	This is useful when it's necessary to convey the structure of a URI		Several specifications have defined URI Templates with varying levels
	in a well-defined way. For example, documentation of an interface		of formality, such as WSDL, WADL and OpenSearch. This specification
	exposed by a Web site might use a template to show people how to find		is derived from these concepts, giving a rigorous definition to such
	information about a user;		templates.
			This specification uses the terms "character" and "coded character
			set" in accordance with the definitions provided in [RFC2978], and
			"character encoding" in place of what [RFC2978] refers to as a
			"charset".
			1.1. Overview
			A URI Template allows a structural description of URIs while allowing
			a consumer of the template to construct a final URI by providing the
			values of the expansion variables. For example, given the following
			URI Template:
	http://www.example.com/users/{userid}		http://www.example.com/users/{userid}
	URI Templates can also be thought of as the basis of a machine-		And the following variable value
	readable forms language; by allowing clients to form their own
	identifiers based on templates given to them by the URI's authority,		userid := fred
	it's possible to construct dynamic systems that use more of the URI
	than traditional HTML forms are able to. For example,		The expansion of the URI Template is:
			http://www.example.com/users/fred
			URI Templates can be used as a machine-readable forms language. By
			allowing clients to form their own identifiers based on templates
			given to them by the URI's authority it's possible to construct
			dynamic systems that use more of the URI than traditional HTML forms.
			For example:
	http://www.example.org/products/{upc}/buyers?page={page_num}		http://www.example.org/products/{upc}/buyers?page={page_num}
	Finally, URI Templates can be used to compose URI-centric protocols		URI Templates can also be used to compose URI-centric protocols
	without impinging on authorities' control of their URIs. For		without impinging on authorities' control of their URI space. For
	example, there are many emerging conventions for passing around login		example, there are many emerging conventions for passing around login
	information between sites using URIs. Forcing people to use a well-		information between sites using URIs. Forcing people to use a well-
	known query parameter isn't good practice, but using a URI parameter		known query parameter isn't good practice, but using URI Templates
	allows different sites to specify local ways of conveying the same		allows different sites to specify local ways of conveying the same
	information;		information:
	http://login.example.org/login?back={return-uri}
	http://auth.example.com/userauth;{return-uri}		http://auth.example.com/userauth;{return-uri}
	This specification defines the basic syntax and processing of URI		http://login.example.org/login?back={return-uri}
	Templates. Each application of URI Templates will need to define its
	own profile of this specification that indicates what template
	variables are available, how to convey them to clients, and what
	their appropriate use is in that context.
	2. Notational Conventions		1.2. Design Considerations
			The URI Template syntax has been designed to carefully balance the
			need for a powerful substitution mechanism with ease of
			implementation and security. The syntax is designed to be easy to
			parse while at the same time providing enough flexibility to express
			many common templating scenarios. On the balance, the template
			processing is not Turing complete, thus avoiding a number of security
			issues, ala the billion-laughs attack of XML DTDs.
			Another consideration was to keep the syntax and processing in-line
			with the pre-existing templating schemes present in OpenSearch, WSDL
			and WADL.
			The final design consideration was control over the placement of
			reserved characters in the URI generated from a URI Template. The
			reserved characters in a URI Template can only appear in the non-
			expansion text, or in the argument to an operator, both locations are
			dictated by the URI Template author. Given the percent-encoding
			rules for variable values this means that the source of all
			structure, i.e reserved characters, in a URI generated from a URI
			Template is decided by the URI Template author.
			1.3. Notational Conventions
			This specification uses the Augmented Backus-Naur Form (ABNF)
			notation of [RFC4234], including the following core ABNF syntax rules
			defined by that specification: ALPHA (letters) and DIGIT (decimal
			digits). See [RFC3986] for the definitions of the URI-reference,
			percent-encoded, reserved, and unreserved rules.
	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 [RFC2119].		document are to be interpreted as described in [RFC2119].
	This specification uses the Augmented Backus-Naur Form (ABNF)		2. Characters
	notation of [RFC4234]. See [RFC3986] for the definitions of the URI-
	reference, reserved, and unreserved rules.		A URI Template is a sequence of characters, and has the same issues
			as URIs with regard to codepoints and character sets. That is, URI
			Template characters are frequently encoded as octets for transport or
			presentation. This specification does not mandate any particular
			character encoding for mapping between URI characters and the octets
			used to store or transmit those characters. When a URI appears in a
			protocol element, the character encoding is defined by that protocol;
			without such a definition, a URI is assumed to be in the same
			character encoding as the surrounding text.
			The ABNF notation defines its terminal values to be non-negative
			integers (codepoints) based on the US-ASCII coded character set
			[ASCII]. Because a URI is a sequence of characters, we must invert
			that relation in order to understand the URI syntax. Therefore, the
			integer values used by the ABNF must be mapped back to their
			corresponding characters via US-ASCII in order to complete the syntax
			rules.
	3. URI Template		3. URI Template
	A URI Template is a sequence of characters that contains one or more		A URI Template is a sequence of characters that contains one or more
	embedded template variables, see Section 3.1. A URI Template becomes		embedded template expansions, see Section 3.2. Each expansion
	a URI when the template variables are substituted with their values		references one or more variables whose values are used in when
	(see Section 3.2). For example:		determining the substition value for an expansion. A URI Template
			becomes a URI when the template expansions are substituted with their
			values (see Section 3.3). The generated URI will be a URI-reference,
			i.e. either an absolute URI or a relative reference.
	http://example.com/widgets/{widget_id}		3.1. Variables
	If the value of the widget_id variable is "xyzzy", the resulting URI		The value of every non-list variable, and the individual values in
	after substitution is:		list variables, must come from ( unreserved / pct-encoded ). For
			variable values that are strings that have characters outside that
			range, the entire string must be converted into UTF-8 [RFC3629], and
			then every octet of the UTF-8 string that falls outside of (
			unreserved / pct-encoded ) MUST be percent-encoded, as per [RFC3986],
			section 2.1.
	http://example.com/widgets/xyzzy		This does not imply that every variable value can be decoded into a
			Unicode string. For example, a variable value may be a binary blob
			that has been percent-encoded before being passed into the template
			processor.
	3.1. Template Variables		The Unicode Standard [UNIV4] defines various equivalences between
			sequences of characters for various purposes. Unicode Standard Annex
			#15 [UTR15] defines various Normalization Forms for these
			equivalences, in particular Normalization Form C (NFC, Canonical
			Decomposition, followed by Canonical Composition) and Normalization
			Form KC (NFKC, Compatibility Decomposition, followed by Canonical
			Composition). Since different Normalized Forms unicode strings will
			have different UTF-8 represenations it is RECOMMEDED that unicode
			strings use Normalized Form NFC.
	Template variables are the parameterized components of a URI		The meaning of 'defined' for a variable is progamming language and
	Template. A template variable MUST match the template-var rule.		library specific and beyond the scope of this specification. Also
			beyond the scope of this specification is the allowable programming
			constructs that can be used for a list variable used in the
			'listjoin' operator. For example, a Python implementation might
			allow only built-in list types, or it may allow any iterable to be
			used as the source for a list variable.
	template-char = unreserved		A variable may appear in more than one expansion in a URI Template.
	template-name = 1*template-char		The value used for that variable must remain the same for every
	template-var = "{" template-name "}"		template expansion when converting a URI Template into a URI.
	3.2. URI Template Substitution		3.2. Template Expansions
	Evaluating a URI Template ("substitution") consists of replacing all		Template expansions are the parameterized components of a URI
	template variables with their respective string values.		Template. A template expansion MUST match the 'expansion' rule.
	During substitution, the string value of a template variable MUST		op = 1*ALPHA
	have any characters that do not match the reserved or unreserved		arg = *(reserved / unreserved / pct-encoded)
	rules (i.e., those characters not legal in URIs without percent		var = varname [ '=' vardefault ]
	encoding) percent-encoded, as per [RFC3986], section 2.1. Specific		vars = var [ *("," var) ]
	applications of URI Templates MAY specify additional constraints and		varname = (ALPHA / DIGIT)*(ALPHA / DIGIT / "." / "_" / "-" )
	encoding rules in addition to this.		vardefault = *(unreserved / pct-encoded)
			operator = "-" op "|" arg "|" vars
			expansion = "{" ( var / operator ) "}"
	Any number of template variables MAY appear in a URI Template; a		3.3. URI Template Substitution
	single template-name MAY appear multiple times.
	The result of substitution MUST match the URI-reference rule and		Template substitution is the process of turning a URI Template into a
	SHOULD also match any known rules for the scheme of the resulting		URI given definitions for the variables used in the template.
	URI.		Substitution replaces each expansion with its calculated value.
	Typically, this is ensured by the definitions of the template		Every expansion consists of either a variable ('var') or an operator
	variables used. For example, they may specify that a variable's		expression. In a variable ('var') expansion, if the variable is
	value is not to contain certain characters, or that some characters		defined and non-empty then substitute the value of the variable,
	should be percent-encoded before substitution.		otherwise substitute the default value. If no default value is given
			then substitute with the empty string.
	3.3. Using URI Templates		If the expansion is an operator then the substitution value is
			determined by the given operator. Each operator works only on the
			variables that are defined within their expansion.
	Applications using URI Templates will typically need to specify a		3.3.1. The 'opt' operator
	number of things, including;
	o The template to use.		If the one or more of the variables are defined and non-empty then
	o What template variables are available.		substitute the value of 'arg', otherwise substitute the empty string.
	o For each of the variables;
	* What characters are allowed in the template's value.
	* What encodings should be applied to the value before
	substitutions.
	* How to handle errors such as the output of substitution being
	an invalid URI.
	URI Template processors SHOULD allow applications to indicate that;		3.3.2. The 'neg' operator
	o A variable's value is required to contain at least one character		If all of the variables are un-defined or empty then substitute the
	o A variable's value is required to match one of a set of supplied		value of arg, otherwise substitute the empty string.
	options
	o A variable's value is to have all reserved characters, as per
	RFC3986, percent-escaped before substitution
	Processors MAY make additional options available.		3.3.3. The 'prefix' operator
	3.3.1. Examples		The prefix operator MUST only have one variable in its expansion. If
			the variable is defined and non-empty then substitute the value of
			arg followed by the value of the variable, otherwise substitute the
			empty string.
	Given the following template names and values:		3.3.4. The 'append' operator
	+--------+--------------------------+		The append operator MUST only have one variable in its expansion. If
			the variable is defined and non-empty then substitute the value of
			the variable followed by the value of arg, otherwise substitute the
			empty string.
			3.3.5. The 'join' operator
			For each variable that is defined and non-empty create a keyvalue
			string that is the concatenation of the variable name, "=", and the
			variable value. Concatenate more than one keyvalue string with
			intervening values of arg to create the substitution value.
			3.3.6. The 'listjoin' operator
			The listjoin operator MUST have only one variable in its expansion
			and that variable must be a list. If the list is non-empty then
			substitute the concatenation of all the list members with intevening
			values of arg.
			The result of substitution MUST match the URI-reference rule and
			SHOULD also match any known rules for the scheme of the resulting
			URI.
			3.4. Examples
			Given the following template variable names and values:
			+----------+--------------------+
	| Name | Value |		| Name | Value |
	+--------+--------------------------+		+----------+--------------------+
	| a | fred |		| a | foo |
	| b | barney |		| b | bar |
	| c | cheeseburger |		| data | 10,20,30 |
	| d | one two three |		| points | ["10","20", "30"] |
	| e | 20% tricky |		| list0 | [] |
	| f | |		| str0 | |
	| 20 | this-is-spinal-tap |		| reserved | :/?#[]@!$&'()*+,;= |
	| scheme | https |		| u | \u2654\u2655 |
	| p | quote=to+be+or+not+to+be |		| a_b | baz |
	| q | hullo#world |		+----------+--------------------+
	+--------+--------------------------+
	Table 1		Table 1
	(Note that the name 'wilma' has not been defined, and the value of		The name 'foo' has not been defined, the value of 'str0' is the empty
	'f' is the empty string.)		string, and both list0 and points are lists. The variable 'u' is a
			string of two unicode characters, the WHITE CHESS KING (0x2654) and
			the WHITE CHESS QUEEN (0x2655).
	The following URI Templates will be expanded as shown:		The following URI Templates will be expanded as shown:
	http://example.org/page1#{a}		----
	http://example.org/page1#fred		http://example.org/?q={a}
			http://example.org/?q=foo
	http://example.org/{a}/{b}/		http://example.org/{foo}
	http://example.org/fred/barney/		http://example.org/
	http://example.org/{a}{b}/		relative/{reserved}/
	http://example.org/fredbarney/		relative/%3A%2F%3F%23%5B%5D%40%21%24%26%27%28%29%2A%2B%2C%3B%3D/
	http://example.com/order/{c}/{c}/{c}/		http://example.org/{foo=fred}
	http://example.com/order/cheeseburger/cheeseburger/cheeseburger/		http://example.org/fred
	http://example.org/{d}		http://example.org/{foo=%25}/
	http://example.org/one%20two%20three		http://example.org/%25/
	http://example.org/{e}		/{-prefix|#|foo}
	http://example.org/20%25%20tricky		/
	http://example.com/{f}/		./{-prefix|#|str0}
	http://example.com//		./
	{scheme}://{20}.example.org?date={wilma}&option={a}		/{-append|/|a}{-opt|data|points}{-neg|@|a}{-prefix|#|b}
	https://this-is-spinal-tap.example.org?date=&option=fred		/foo/data#bar
	http://example.org?{p}		http://example.org/q={u}
	http://example.org?quote=to+be+or+not+to+be		http://example.org/q=%E2%99%94%E2%99%95
	http://example.com/{q}		http://example.org/?{-join|&|a,data}
	http://example.com/hullo#world		http://example.org/?a=foo&data=10%2C20%2C30
			http://example.org/?d={-listjoin|,|points}&{-join|&|a,b}
			http://example.org/?d=10,20,30&a=foo&b=bar
			http://example.org/?d={-listjoin|,|list0}&{-join|&|foo}
			http://example.org/?d=&
			http://example.org/?d={-listjoin|&d=|points}
			http://example.org/?d=10&d=20&d=30
			http://example.org/{a}{b}/{a_b}
			http://example.org/foobar/baz
			http://example.org/{a}{-prefix|/-/|a}/
			http://example.org/foo/-/foo/
			----
	4. Security Considerations		4. Security Considerations
	A URI Template does not contain active or executable content. Other		A URI Template does not contain active or executable content. Other
	security considerations are the same as those for URIs, see section 7		security considerations are the same as those for URIs, see section 7
	of RFC3986.		of RFC3986.
	5. IANA Considerations		5. IANA Considerations
	In common with RFC3986, URI scheme names form a registered namespace		In common with RFC3986, URI scheme names form a registered namespace
	that is managed by IANA according to the procedures defined in		that is managed by IANA according to the procedures defined in
	[RFC4395]. No IANA actions are required by this document.		[RFC4395]. No IANA actions are required by this document.
	6. Normative References		6. Appendix A - Parsing URI Template Expansions
			Parsing a valid URI Template expansion does not require building a
			parser from the given ABNF. Instead, the set of allowed characters
			in each part of URI Template expansion has been chosen to avoid
			complex parsing, and breaking an expansion into its component parts
			can be achieved by a series of splits of the character string.
			Here is example Python code that parses a URI Template expansion and
			returns the operator, argument, and variables as a tuple. The
			variables are returned as a dictionary of variable names mapped to
			their default values. If no default is given then the name maps to
			None.
			def parse_expansion(expansion):
			if "|" in expansion:
			(op, arg, vars_) = expansion.split("|")
			op = op[1:]
			else:
			(op, arg, vars_) = (None, None, expansion)
			vars_ = vars_.split(",")
			variables = {}
			for var in vars_:
			if "=" in var:
			(varname, vardefault) = var.split("=")
			else:
			(varname, vardefault) = (var, None)
			variables[varname] = vardefault
			return (op, arg, variables)
			And here is an example of the parse_expansion() function being used.
			>>> parse_expansion("-join|&|a,b,c=1")
			('join', '&', {'a': None, 'c': '1', 'b': None})
			>>> parse_expansion("c=1")
			(None, None, {'c': '1'})
			7. Normative References
			[ASCII] American National Standards Institute, "Coded Character
			Set - 7-bit American Standard Code for Information
			Interchange", ANSI X3.4, 1986.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Requirement Levels", BCP 14, RFC 2119, March 1997.		Requirement Levels", BCP 14, RFC 2119, March 1997.
			[RFC2978] Freed, N. and J. Postel, "IANA Charset Registration
			Procedures", BCP 19, RFC 2978, October 2000.
			[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
			10646", STD 63, RFC 3629, November 2003.
	[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform		[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
	Resource Identifier (URI): Generic Syntax", STD 66,		Resource Identifier (URI): Generic Syntax", STD 66,
	RFC 3986, January 2005.		RFC 3986, January 2005.
	[RFC4234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax		[RFC4234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
	Specifications: ABNF", RFC 4234, October 2005.		Specifications: ABNF", RFC 4234, October 2005.
	[RFC4395] Hansen, T., Hardie, T., and L. Masinter, "Guidelines and		[RFC4395] Hansen, T., Hardie, T., and L. Masinter, "Guidelines and
	Registration Procedures for New URI Schemes", BCP 115,		Registration Procedures for New URI Schemes", BCP 115,
	RFC 4395, February 2006.		RFC 4395, February 2006.
			[UNIV4] The Unicode Consortium, "The Unicode Standard, Version
			4.0.1, defined by: The Unicode Standard, Version 4.0
			(Reading, MA, Addison-Wesley, 2003. ISBN 0-321-18578-1),
			as amended by Unicode 4.0.1
			(http://www.unicode.org/versions/Unicode4.0.1/)",
			March 2004.
			[UTR15] Davis, M. and M. Duerst, "Unicode Normalization Forms",
			Unicode Standard Annex # 15, April 2003.
	[1] <http://lists.w3.org/Archives/Public/uri/>		[1] <http://lists.w3.org/Archives/Public/uri/>
	Appendix A. Contributors		Appendix A. Contributors
	The following people made significant contributions to this		The following people made significant contributions to this
	specification: DeWitt Clinton and James Snell.		specification: DeWitt Clinton and James Snell.
	Appendix B. Revision History		Appendix B. Revision History
			02 - Added operators and came up with coherent percent-encoding and
			reserved character story. Added large examples section which is
			extracted and tested against the implementation.
	01		01
	00 - Initial Revision.		00 - Initial Revision.
	Authors' Addresses		Authors' Addresses
	Joe Gregorio (editor)		Joe Gregorio (editor)
			Google
	Email: joe@bitworking.org		Email: joe@bitworking.org
	URI: http://bitworking.org/		URI: http://bitworking.org/
	Marc Hadley (editor)		Marc Hadley (editor)
	Sun Microsystems		Sun Microsystems
	Email: Marc.Hadley@sun.com		Email: Marc.Hadley@sun.com
	URI: http://sun.com/		URI: http://sun.com/
	Mark Nottingham (editor)		Mark Nottingham (editor)
	Email: mnot@pobox.com		Email: mnot@pobox.com
	URI: