Internet DRAFT - draft-hamrick-vwrap-launch

draft-hamrick-vwrap-launch






Virtual World Region Agent                                    M. Hamrick
Protocol                                           Linden Research, Inc.
Internet-Draft                                               J. Hurliman
Intended status: Informational                         Intel Corporation
Expires: August 16, 2010                               February 12, 2010


Virtual World Region Agent Protocol : Client Application Launch Message
                     draft-hamrick-vwrap-launch-00

Abstract

   This document describes the LLIDL interface description for the
   Virtual World Region Agent Protocol (VWRAP) Client Application Launch
   message format.  Messages in this format are intended to be used in
   conjunction with standard web authentication or authorization
   technologies such as OpenID or OAuth.  This document describes the
   message format, the processing expectations and three MIME types that
   may be used to identify requests to initiate a virtual worlds
   session.

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on August 16, 2010.

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.



Hamrick & Hurliman       Expires August 16, 2010                [Page 1]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the BSD License.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Requirements Language  . . . . . . . . . . . . . . . . . .  3
   2.  The VWRAP Client Application Launch Message Format . . . . . .  3
   3.  Message Flow . . . . . . . . . . . . . . . . . . . . . . . . .  4
   4.  Processing Expectations  . . . . . . . . . . . . . . . . . . .  6
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  6
   6.  MIME Type Registrations  . . . . . . . . . . . . . . . . . . .  7
     6.1.  MIME Type Registration for application/calm+xml  . . . . .  7
     6.2.  MIME Type Registration for application/calm+json . . . . .  8
     6.3.  MIME Type Registration for application/calm+binary . . . .  9
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 10
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 11
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 11
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 11
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12























Hamrick & Hurliman       Expires August 16, 2010                [Page 2]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


1.  Introduction

   Web authentication protocols such as OpenID [OPENID] and web
   authorization protocols such as OAuth [I-D.hammer-oauth] are of
   increasing interest to the internet community.  They have great
   utility in web-based application environments.  Best practice for
   their use in conjunction with applications that do not expose a HTML
   rendering interface is less clear.  Virtual World (VW) client
   applications, for instance, are often implemented as "desktop
   applications" instead of "web apps".  This introduces difficulty in
   using web based authentication and authorization protocols to
   initiate a virtual world session.

   OpenID and OAuth traditionally use a HTTP redirect [RFC2616] after
   user or token authentication to begin an authorized session with a
   web application.  The problem in using desktop applications with "web
   auth" technologies is that desktop applications do not generally have
   a URL to act as the target of HTTP redirection.

   One possible solution to this problem is to register a unique MIME
   type [RFC2046] with the user's web browser and following successful
   user or token authentication, redirect the user's web browser to a
   resource with that MIME type.  Upon receipt of such a resource, a
   properly configured web browser could then launch the client desktop
   application.

   This document describes the format of a web resource suitable for
   signaling the user's web browser to launch a virtual world client
   application that uses Virtual World Region Agent Protocol (VWRAP)
   Authentication [I-D.hamrick-vwrap-authentication] to establish a
   session between the client application and network resources
   implementing the virtual world.

1.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].


2.  The VWRAP Client Application Launch Message Format

   The Client Application Launch message is an LLSD
   [I-D.hamrick-vwrap-type-system] message, defined by the LLIDL below,
   but is identified with a unique MIME type (described below.)  It may
   be transmitted in XML, JSON or Binary format, at the web server's
   convenience.  Compliant client applications SHOULD support XML, JSON
   and Binary serialization formats.



Hamrick & Hurliman       Expires August 16, 2010                [Page 3]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


   ; note that the &request defined here uses named types &authenticator
   ; and &identifier which are defined in
   ; draft-hamrick-vwrap-authentication-00

   &request = {
     authenticator : &authenticator,
     identifier : &identifier,
     loginurl : uri,
     region : uri
   }

   %% launch_request << &request

   Figure 1 : VWRAP Client Application Launch Message


3.  Message Flow

   The VWRAP Client Application Launch Message is intended to be sent by
   a web server to a web browser following successful authentication.
   Requirements for web authentication are explicitly not defined in
   this document, and left as a responsibility of the authenticating web
   service.

   Two techniques for processing a client application launch message are
   defined.  The first requests a one time "single use only" secret from
   an agent domain.  This secret is used to authenticate the client to
   the agent domain.  The second technique uses possession of a web
   capability to authenticate the client.  The message flow for both
   techniques is the same.

   Figure 2 below shows message flows between four conceptual entities.
   It is provided for expository purposes only; implementers may choose
   to combine conceptual entities into fewer reified components.  That
   is, nothing in this specification should be interpreted to require
   four distinct, deployed entities.















Hamrick & Hurliman       Expires August 16, 2010                [Page 4]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


   +------------------+        2.       +------------------+
   |                  |---------------->|                  |
   | Web Auth Service |        3.       | VWRAP Agent Domain |
   |                  |<----------------|                  |
   +------------------+                 +------------------+
          ^     |                              ^
       1. |     | 4.                           | 6.
          |     v                              |
   +------------------+        5.       +------------------+
   |                  |---------------->|                  |
   |    Web Browser   |                 |  VWRAP Client App  |
   |                  |                 |                  |
   +------------------+                 +------------------+

   Figure 2 : Message Flow For Client Application Launch Requests

   0. Registering MIME types as Web Browser Helper Applications  The
       technique defined in this document depends on the traditional web
       browser capability to define a "helper application" when the
       browser receives a MIME type it cannot handle itself.  Compliant
       VWRAP Client Applications SHOULD register themselves as the
       helper application for the three MIME types listed in IANA
       Considerations (Section 5) below.

       The exact technique used to register the client application with
       the VWRAP Client Application Launch Message is beyond the scope
       of this document.

   1. Web Client to Web Server Authentication / Authorization  The
       process of launching an VWRAP client application using a web
       based authentication or authorization system begins with
       successful user authentication or token authentication.  It is
       traditional in these systems for the user's web browser to be
       redirected to a web based application following authentication.
       This document assumes the user's web browser will instead be
       redirected to an HTTP or HTTPS URI that will eventually respond
       with a Client Application Launch Message.

       The exact nature of the web-based authentication or authorization
       scheme used is beyond the scope of this document.

   2. One Time Password or LoginURL Capability Request  Before the web
       service responsible for communicating the launch message to the
       user's web browser may download the message, it must first
       request a "single use only" shared secret or the LoginURL web
       capability.

       The exact mechanism for this request is beyond the scope of this



Hamrick & Hurliman       Expires August 16, 2010                [Page 5]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


       document.  However, the request from the authentication service
       to the agent domain SHOULD contain an account or avatar name
       known to the agent domain and SHOULD be communicated over a
       secure channel.

   3. One Time Password or LoginURL Capability Response  The agent
       domain responds with a One Time Password or web capability.  If
       the one time password is used, the password SHOULD be a sequence
       of unguessable octets, thought the exact encoding and transport
       of the request is beyond the scope of this document.

   4. Client Application Launch Download  After the One Time Password or
       web capability is passed from the agent domain to the
       authorization service, it is included in the Client Application
       Launch Message along with an account or avatar identifier, a
       login URI for the agent domain and an initial region URI
       indicating the avatar's initial location in the virtual world.

   5. Web Browser Launches Client Application  When the user's web
       browser receives the Client Application Launch Message, it
       forwards the contents of the message AND the message's MIME type
       to the registered Client Application.

   6. VWRAP Authentication  In response to receipt of the Client
       Application Launch Message, the client application uses the
       information in the message to begin the VWRAP Authentication
       process and initial placement of the user's avatar in the virtual
       world.


4.  Processing Expectations

   When a client application receives a client application launch
   message, it is expected to request a seed capability from the service
   endpoint from in the loginurl specified in message.  The loginurl is
   expected to identify the service endpoint for an agent_login resource
   defined in the VWRAP Trust Model and User Authentication
   [I-D.hamrick-vwrap-authentication] specification.  The client SHOULD
   pass the &authenticator and &identifier map entries to the
   agent_login resource unaltered.


5.  IANA Considerations

   In accordance with [RFC5226], this document registers the following
   mime types:





Hamrick & Hurliman       Expires August 16, 2010                [Page 6]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


       application/calm+xml

       application/calm+json

       application/calm+binary

   See the MIME Type Registrations section (Section 6) below for
   detailed information on MIME Type registrations.


6.  MIME Type Registrations

   This section provides media-type registration applications (as per
   RFC 4288 [RFC4288].)

6.1.  MIME Type Registration for application/calm+xml

   To: ietf-types@iana.org

   Subject: Registration of media type application/calm+xml

   Type name: application

   Subtype name: calm+xml

   Required Parameters: none

   Optional Parameters: none

   Encoding Considerations:  The Extensible Markup Language (XML)
       specification allows for the use of multiple character sets.  The
       character set used to encode the body of the message is defined
       as part of the XML header.  If no character set is indicated in
       the XML header, compliant systems MUST assume UTF-8.  When
       encoding binary data using RFC 4648 [RFC4648], characters outside
       the base alphabet are explicitly allowable and should be ignored.

   Security Considerations:  The VWRAP Client Application Launch Request
       Message contains sensitive information.  Compliant systems SHOULD
       ensure the confidentiality of the communications media between
       the web authentication service and the VWRAP agent domain as well
       as that between the web authentication service and the user's web
       browser.

   Interoperability Considerations:  While it is possible for compliant
       implementations to specify the use of character sets other than
       UTF-8, such systems MUST accept UTF-8 input and SHOULD generate
       UTF-8 output.



Hamrick & Hurliman       Expires August 16, 2010                [Page 7]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


   Published specification: this specification.

   Applications that use this media type:  Virtual world, tele-presence
       and content management systems related to "virtual reality"
       systems.

   Additional Information:

       Magic Number(s): none

       File Extension: calmx

       Macintosh File Type Code(s): CALX

   Person & email address to contact for further information:  Meadhbh
       Hamrick <infinity@lindenlab.com>

   Intended Usage: COMMON

   Author: IESG

   Change Controller: IESG

6.2.  MIME Type Registration for application/calm+json

   To: ietf-types@iana.org

   Subject: Registration of media type application/calm+json

   Type name: application

   Subtype name: calm+json

   Required Parameters: none

   Optional Parameters: none

   Encoding Considerations: Use of Unicode is Mandatory  ECMA-262
       [ECMA262r5] requires the use of Unicode, but allows the use of
       UTF-8, UTF-16 or UTF-32 character encodings.

   Security Considerations:  The VWRAP Client Application Launch Request
       Message contains sensitive information.  Compliant systems SHOULD
       ensure the confidentiality of the communications media between
       the web authentication service and the VWRAP agent domain as well
       as that between the web authentication service and the user's web
       browser.




Hamrick & Hurliman       Expires August 16, 2010                [Page 8]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


   Interoperability Considerations:  none

   Published specification: This specification.

   Applications that use this media type:  Virtual world, tele-presence
       and content management systems related to "virtual reality"
       systems.

   Additional Information:

       Magic Number(s): none

       File Extension: calmj

       Macintosh File Type Code(s): CALJ

   Person & email address to contact for further information:  Meadhbh
       Hamrick <infinity@lindenlab.com>

   Intended Usage: COMMON

   Author: IESG

   Change Controller: IESG

6.3.  MIME Type Registration for application/calm+binary

   To: ietf-types@iana.org

   Subject: Registration of media type application/calm+binary

   Type name: application

   Subtype name: calm+binary

   Required Parameters: none

   Optional Parameters: none

   Encoding Considerations: LLSD Binary Serialization REQUIRES the use
   of binary content-transfer-encoding  Section 5 of RFC 2045 [RFC2045]
       describes the binary Content-Transfer-Encoding header field.
       This specification REQUIRES the use of this header to alert
       intermediary systems that information being included in the
       message should be interpreted as binary data with no end-of-line
       semantics which could be considerably longer than allowed in an
       RFC 821 transport.




Hamrick & Hurliman       Expires August 16, 2010                [Page 9]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


   Security Considerations:  The VWRAP Client Application Launch Request
       Message contains sensitive information.  Compliant systems SHOULD
       ensure the confidentiality of the communications media between
       the web authentication service and the VWRAP agent domain as well
       as that between the web authentication service and the user's web
       browser.

   Interoperability Considerations: none

   Published specification: This specification.

   Applications that use this media type:  Virtual world, tele-presence
       and content management systems related to "virtual reality"
       systems.

   Additional Information:

       Magic Number(s): none

       File Extension: calb

       Macintosh File Type Code(s): CALB

   Person & email address to contact for further information:  Meadhbh
       Hamrick <infinity@lindenlab.com>

   Intended Usage: COMMON

   Author: IESG

   Change Controller: IESG


7.  Security Considerations

   Security considerations for this specification are, fortunately,
   either simple or beyond the scope of this document.  RFC 3552
   [RFC3552] describes several aspects to use when evaluating the
   security of a specification or implementation.  The authors believe
   most common security concerns users of this specification will
   encounter are more appropriately considered as transport, network or
   link layer issues.  Or, as higher level "application security"
   issues.


8.  References





Hamrick & Hurliman       Expires August 16, 2010               [Page 10]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


8.1.  Normative References

   [ECMA262r5]
              ECMA International, "Standard ECMA-262, 5th Edition :
              ECMAScript Language Specification", December 2009, <http:/
              /www.ecma-international.org/publications/standards/
              Ecma-262.htm>.

   [I-D.hammer-oauth]
              Hammer-Lahav, E. and B. Cook, "The OAuth Core Protocol",
              draft-hammer-oauth-02 (work in progress), March 2009.

   [I-D.hamrick-vwrap-authentication]
              Chu, T., Hamrick, M., and M. Lentczner, "VWRAP Trust Model
              and User Authentication",
              draft-hamrick-vwrap-authentication-00 (work in progress),
              February 2010.

   [I-D.hamrick-vwrap-type-system]
              Brashears, A., Hamrick, M., and M. Lentczner, "VWRAP :
              Abstract Type System for the Transmission of Dynamic
              Structured Data", draft-hamrick-vwrap-type-system-00 (work
              in progress), February 2010.

   [OPENID]   OpenID Foundation, "OpenID Authentication 2.0 - Final",
              2007.

   [RFC2045]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part One: Format of Internet Message
              Bodies", RFC 2045, November 1996.

   [RFC2046]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part Two: Media Types", RFC 2046,
              November 1996.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4288]  Freed, N. and J. Klensin, "Media Type Specifications and
              Registration Procedures", BCP 13, RFC 4288, December 2005.

   [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", RFC 4648, October 2006.

8.2.  Informative References

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext



Hamrick & Hurliman       Expires August 16, 2010               [Page 11]

Internet-Draft  VWRAP : Client Application Launch Message  February 2010


              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC3552]  Rescorla, E. and B. Korver, "Guidelines for Writing RFC
              Text on Security Considerations", BCP 72, RFC 3552,
              July 2003.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.


Authors' Addresses

   Meadhbh Siobhan Hamrick
   Linden Research, Inc.
   945 Battery St.
   San Francisco, CA  94111
   US

   Phone: +1 650 283 0344
   Email: infinity@lindenlab.com


   John Hurliman
   Intel Corporation
   3600 Juliette Lane
   Santa Clara?, CA  95051
   US

   Phone: +1 408 123 4560
   Email: john.hurliman@intel.com




















Hamrick & Hurliman       Expires August 16, 2010               [Page 12]