Internet DRAFT - draft-oauth-dyn-reg-v1
draft-oauth-dyn-reg-v1
Network Working Group T. Hardjono, Ed.
Internet-Draft MIT
Intended status: Standards Track M. Machulak
Expires: April 26, 2012 Newcastle University
E. Maler
XMLgrrl.com
C. Scholz
COM.lounge GmbH
October 24, 2011
OAuth Dynamic Client Registration Protocol
draft-oauth-dyn-reg-v1-03
Abstract
This specification proposes an OAuth Dynamic Client Registration
protocol.
Status of this Memo
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provisions of BCP 78 and BCP 79.
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Internet-Drafts are draft documents valid for a maximum of six months
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This Internet-Draft will expire on April 26, 2012.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
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include Simplified BSD License text as described in Section 4.e of
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Notational Conventions . . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. The client needs to be uniquely identifiable by the
authorization server . . . . . . . . . . . . . . . . . . . 5
3.2. The authorization server must collect metadata about a
client for later user interaction . . . . . . . . . . . . 5
3.3. The authorization server must have the option of
strongly authenticating the client and its metadata . . . 5
3.4. Dynamic client registration must be possible from both
web-server applications and applications with other
capabilities and limitations, such as native
applications . . . . . . . . . . . . . . . . . . . . . . . 6
3.5. Transaction integrity must be ensured in large
deployments where data propagation can be an issue . . . . 6
3.6. UMA design principles and requirements . . . . . . . . . . 6
4. Analysis of Registration Flow Options . . . . . . . . . . . . 7
5. Discovery of Server's Client Registration Endpoint . . . . . . 8
6. Client Registration with Pushed Metadata . . . . . . . . . . . 9
6.1. Client Registration Request . . . . . . . . . . . . . . . 9
6.2. Client Registration Response . . . . . . . . . . . . . . . 10
6.3. Error Response . . . . . . . . . . . . . . . . . . . . . . 11
7. Client Registration with Pushed URL and Pulled Metadata . . . 12
7.1. Client Registration Request . . . . . . . . . . . . . . . 13
7.2. Client Discovery . . . . . . . . . . . . . . . . . . . . . 14
7.3. Client Registration Response . . . . . . . . . . . . . . . 15
7.4. Error Response . . . . . . . . . . . . . . . . . . . . . . 16
8. Native Application Client Registration . . . . . . . . . . . . 17
9. Security Considerations . . . . . . . . . . . . . . . . . . . 18
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 18
11. Document History . . . . . . . . . . . . . . . . . . . . . . . 18
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
12.1. Normative References . . . . . . . . . . . . . . . . . . . 19
12.2. Non-Normative References . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 20
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1. Introduction
This informal draft discusses a number of requirements for and
approaches to automatic registration of clients with an OAuth
authorization server, with special emphasis on the needs of the
OAuth-based User-Managed Access protocol [UMA-Core].
In some use-case scenarios it is desirable or necessary to allow
OAuth clients to obtain authorization from an OAuth authorization
server without the two parties having previously interacted.
Nevertheless, in order for the authorization server to accurately
represent to end-users which client is seeking authorization to
access the end-user's resources, a method for automatic and unique
registration of clients is needed.
The goal of this proposed registration protocol is for an
authorization server to provide a client with a client identifier and
optionally a client secret in a dynamic fashion. To accomplish this,
the authorization server must first be provided with information
about the client, with the client-name being the minimal information
provided. In practice, additional information will need to be
furnished to the authorization server, such as the client's homepage,
icon, description, and so on.
The dynamic registration protocol proposed here is envisioned to be
an additional task to be performed by the OAuth authorization server,
namely registration of a new client identifier and optional secret
and the issuance of this information to the client. This task would
occur prior to the point at which the client wields its identifier
and secret at the authorization server in order to obtain an access
token in normal OAuth fashion.
1.1. Notational Conventions
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 [RFC2119].
Unless otherwise noted, all the protocol parameter names and values
are case sensitive.
1.2. Terminology
resource server
A server capable of accepting and responding to protected
resource requests.
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resource owner
An entity capable of granting access to a protected resource.
client
An application obtaining authorization and making protected
resource requests.
authorization server
A server capable of issuing tokens after successfully
authenticating the resource owner and obtaining authorization.
The authorization server may be the same server as the resource
server, or a separate entity.
authorization manager
An UMA-defined variant of an authorization server that carries
out an authorizing user's policies governing access to a
protected resource.
end-user authorization endpoint
The authorization server's HTTP endpoint capable of
authenticating the end-user and obtaining authorization.
token endpoint
The authorization server's HTTP endpoint capable of issuing
tokens and refreshing expired tokens.
client identifier
An unique identifier issued to the client to identify itself to
the authorization server. Client identifiers may have a
matching secret.
client registration endpoint The authorization server's HTTP
endpoint capable of issuing client identifiers and optional
client secrets.
2. Use Cases
The UMA protocol involves two instances of OAuth flows. In the
first, an end-user introduces a host (essentially an enhanced OAuth
resource server) to an authorization manager (an enhanced OAuth
authorization server) as a client of it, possibly without that host
having obtained client identification information from that server
previously. In the second, a requester (an enhanced OAuth client)
approaches a host and authorization manager to get and use an access
token in approximately the normal OAuth fashion, again possibly
without that client having obtained client identification information
from that server previously. Both the host-as-client and the
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requester-as-client thus may need dynamic client registration in
order for the UMA protocol flow to proceed.
The needs for inter-party trust vary in different UMA use cases. In
lightweight Web circumstances such as person-to-person calendar
sharing, dynamic registration is entirely appropriate. In cases
where high-sensitivity information is being protected or where a
regulatory environment puts constraints on the building of trust
relationships, such as sharing health records with medical
professionals or giving access to tax records to outsourced
bookkeeping staff, static means of provisioning client identifiers
may be imposed.
More information about UMA use cases is available at [UMA-UC].
3. Requirements
Following are proposed requirements for dynamic client registration.
3.1. The client needs to be uniquely identifiable by the authorization
server
In order for an authorization server to do proper user-delegated
authorization and prevent unauthorized access it must be able to
identify clients uniquely. As is done today in OAuth, the client
identifier (and optional secret) should thus be issued by the
authorization server and not simply accepted as proposed by the
client.
3.2. The authorization server must collect metadata about a client for
later user interaction
In order for the authorization server to describe a client to an end-
user in an authorization step it needs information about the client.
This can be the client name at a minimum, but today servers usually
request at least a description, a homepage URL, and an icon when
doing manual registration.
3.3. The authorization server must have the option of strongly
authenticating the client and its metadata
In order to prevent spoofing of clients and enable dynamic building
of strong trust relationships, the authorization server should have
the option to verify the provided information. This might be solved
using message signature verification; relatively weaker
authentication might be achieved in a simpler way by pulling metadata
from a trusted client URL.
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3.4. Dynamic client registration must be possible from both web-server
applications and applications with other capabilities and
limitations, such as native applications
In the UMA context, alternative types of applications might serve as
both hosts (for example, as a device-based personal data store) and
requesters (for example, to subscribe to a calendar or view a photo).
Such applications, particularly native applications, may have special
limitations, so new solutions to meeting the set of requirements
presented here may be needed. We anticipate that each instance of a
native application (that is, the specific instance running on each
device) that is installed and run by the same user may need the
option of getting a unique client identifier. In this case, there
are implications around gathering and displaying enough information
to ensure that the end-user is delegating authorization to the
intended application.
3.5. Transaction integrity must be ensured in large deployments where
data propagation can be an issue
When a client sends information to a server endpoint, it might take
time for this data to propagate through big server installations that
spread across various data centers. Care needs to be taken that
subsequent interactions with the user after the registration process,
such as an authorization request, show the correct data.
In the UMA context, dynamic registration of a host at an AM is almost
certain to take place in the middle of an introduction and
authorization process mediated by the end-user; even though the host
needs a client identifier from the AM no matter which end-user caused
the registration process to take place, the end-user may need to wait
for the registration sub-process to finish in order to continue with
the overall process. It may be necessary to ensure that the host
interacts with the same AM server throughout.
3.6. UMA design principles and requirements
In addition to general requirements for dynamic client registration,
UMA seeks to optimize for the design principles and requirements
found in the UMA Requirements document [UMA-Reqs], most particularly:
o DP1: Simple to understand, implement in an interoperable fashion,
and deploy on an Internet-wide scale
o DP6: Able to be combined and extended to support a variety of use
cases and emerging application functionality
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o DP8: Avoid adding crypto requirements beyond what existing web app
implementations do today
o DP10: Complexity should be borne by the authorization endpoint vs.
other endpoints
4. Analysis of Registration Flow Options
This section analyzes some options for exchanging client metadata for
a client identifier and optional secret.
It currently seems impossible to specify a single registration flow
that will satisfy all requirements, deployment needs, and client
types. This document, therefore, presents as small a variety of
options as possible. If it is possible to construct a single unified
flow in the ultimate design, all other things being equal this would
be preferred.
Client provides metadata on every request
In this approach, the client passes all necessary metadata such
as its name and icon on every request to the authorization
server, and the client doesn't wield a client identifier as
such. This option makes it more difficult (though not
impossible) to meet the first and second requirements since
different clients could theoretically represent themselves to
an authorization server with the same metadata and the same
client could represent itself on subsequent visits with
different metadata. Also, today's OAuth protocol requires the
use of a client identifier. Because of the UMA simplicity
principle we do not recommend this flow option and and have not
provided a candidate solution.
Client pushes metadata
In this approach, the client discovers the registration
endpoint of the authorization server and sends its metadata
directly to that endpoint in a standard format. The
authorization server answers with a client identifier and
optional secret in the response. This approach may be
necessary in cases where the client is behind a firewall, but
strong authentication of the client metadata may be more
difficult or costly with this approach than with a "pull"
approach, discussed just below. Further, this approach is
problematic in the case of applications that can't function as
POST-capable web servers. A proposal for "push" is presented
in this document.
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Client pushes URL, server pulls metadata from it
In this approach, the client sends only a URL to the
authorization server, which then uses that URL to pull metadata
about the client in some standard format, returning
identification information in the response to the initial
request. This approach more easily allows for strong
authentication of clients because the metadata can be
statically signed. (The message containing the URL could be
signed as well.) However, caution should be exercised around
the propagation issue if the initial URL push is made to a
server different from the one the end-user is interacting with.
Further, this approach is problematic in the case of
applications that cannot themselves serve as "pull-able"
metadata repositories. A proposal for "pull" is presented in
this document.
Native-app client collaborates with home-base web app to provide
metadata
An instance of a native application (for example, on a mobile
device) may have difficulty directly conveying trustworthy
metadata but may also have difficulty providing a trustworthy
third-party source from which a server can pull metadata. This
document explores one option for meeting the requirements, but
does not present a full-fledged proposal.
5. Discovery of Server's Client Registration Endpoint
Regardless of flow option, the client needs to discover the
authorization server's client registration endpoint.
The client MUST use the [RFC5785] and [hostmeta] discovery mechanisms
to learn the URI of the client registration endpoint at the
authorization server. The authorization server MUST provide a host-
meta document containing a Link element with a rel value of:
"http://oauth.net/as/registration"
For example:
<XRD>
<Host>http://server.example.com</Host>
<Link rel="http://oauth.net/as/registration"
href="https://server.example.com/register">
<Title>Client Registration Endpoint</Title>
</Link>
</XRD>
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6. Client Registration with Pushed Metadata
This registration flow works as follows:
1. The client sends its metadata in JSON form to the client
registration endpoint. The client MUST send its name,
description, and redirection URI and MAY send a URI for its icon.
The client MAY sign the metadata as a JSON Token issuer, using
the mechanisms defined in [OAuth-Sig].
2. The authorization server checks the data, verifying the signature
as necessary, and returns a client identifier and an optional
client secret.
+--------+ +---------------+
| Client |--(A)--- Registration Request --->| Authorization |
| | with Metadata | Server |
| | | |
| |<-(B)----Registration Response ---| |
| | with Client ID Info | |
+--------+ +---------------+
Figure 1: Client Registration Flow with Pushed Metadata
6.1. Client Registration Request
The client sends a JSON formatted document to the client registration
endpoint. The client includes the following parameters in the
request:
type
REQUIRED. This parameter must be set to "push".
client_name
REQUIRED. This field contains a human-readable name of the
client.
client_url
REQUIRED. This field contains the URL of the homepage of the
client.
client_description
REQUIRED. This field contains a text description of the
client.
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client_icon
OPTIONAL. This field contains a URL for an icon for the
client.
redirect_url
REQUIRED. This field contains the URL to which the
authorization server should send its response.
The client MAY include additional metadata in the request and the
authorization server MAY ignore this additional information.
For example, the client might send the following request:
POST /register HTTP/1.1
Host: server.example.com
Content-Type: application/json
{
type: "push",
client_name: "Online Photo Gallery",
client_url: "http://onlinephotogallery.com",
client_description: "Uploading and also editing capabilities!",
client_icon: "http://onlinephotogallery.com/icon.png",
redirect_url: "https://onlinephotogallery.com/client_reg"
}
The parameters are included in the entity body of the HTTP request
using the "application/json" media type as defined by [JSON]. The
parameters are serialized into a JSON structure by adding each
parameter at the highest structure level. Parameter names and string
values are included as JSON strings.
6.2. Client Registration Response
After receiving and verifying information received from the client,
the authorization server issues a client identifier and an optional
client secret, and constructs the response by adding the following
parameters to the entity body of the HTTP response with a 200 status
code (OK):
client_id
REQUIRED.
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client_secret
OPTIONAL.
issued_at
OPTIONAL. Specifies the timestamp when the identifier was
issued. The timestamp value MUST be a positive integer. The
value is expressed in the number of seconds since January 1,
1970 00:00:00 GMT.
expires_in
OPTIONAL; if supplied, the "issued_at" parameter is REQUIRED.
Specifies the valid lifetime, in seconds, of the identifier.
The value is represented in base 10 ASCII.
The parameters are included in the entity body of the HTTP response
using the "application/json" media type as defined by [JSON]. The
parameters are serialized into a JSON structure by adding each
parameter at the highest structure level. Parameter names and string
values are included as JSON strings.
The authorization server MUST include the HTTP "Cache-Control"
response header field with a value of "no-store" in any response
containing "client_secret".
For example, the authorization server might return the following
response:
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-store
{
client_id: "5UO9XcL4TQTa",
client_secret: "WdRKN3zeTc20"
}
6.3. Error Response
If the request for registration is invalid or unauthorized, the
authorization server constructs the response by adding the following
parameters to the entity body of the HTTP response with a 400 status
code (Bad Request) using the "application/json" media type:
o "error" (REQUIRED).
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o "error_description" (OPTIONAL). Human-readable text providing
additional information, used to assist in the understanding and
resolution of the error occurred.
o "error_uri" (OPTIONAL). A URI identifying a human-readable web
page with information about the error, used to provide the end-
user with additional information about the error.
An example error response (with line breaks for readability):
HTTP/1.1 400 Bad Request
Content-Type: application/json
Cache-Control: no-store
{
"error": "unauthorized_client",
"description": "This client is not on the
white list of this Authorization Server."
}
7. Client Registration with Pushed URL and Pulled Metadata
This registration flow works as follows:
1. The client sends its metadata URI to the client registration
endpoint. The client MAY sign the metadata as a JSON Token
issuer, using the mechanisms defined in [OAuth-Sig].
2. The authorization server verifies the signature as necessary, and
uses the [RFC5785] and [hostmeta] discovery mechanisms on this
URI to retrieve the host-meta document describing the client.
The host-meta document MUST contain the client name, description,
and redirection URI, and MAY contain a URI for the client icon.
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+--------+ +---------------+
| Client |--(A)--- Registration Request --->| Authorization |
| | with URL | Server |
| | | |
| |<-(B)--- Client Discovery --------| |
| | | |
| |--(C)---- Host-Meta Document ---->| |
| | | |
| |<-(D)--- Registration Response ---| |
| | with Client ID Info | |
+--------+ +---------------+
Figure 2: Client Registration Flow with Pushed URL and Pulled
Metadata
7.1. Client Registration Request
The client sends a JSON formatted document to the client registration
endpoint. The client includes the following parameters in the
request:
type
REQUIRED. This parameter must be set to "pull".
client_url
REQUIRED. This field contains the URL of the homepage of the
client.
The client MUST NOT include other metadata parameters, such as those
defined in the pushed-metadata scenario.
For example, the client might send the following request:
POST /register HTTP/1.1
Host: server.example.com
Content-Type: application/json
{
type: "pull",
url: "http://onlinephotogallery.com"
}
The parameters are included in the entity body of the HTTP request
using the "application/json" media type as defined by [JSON]. The
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parameters are serialized into a JSON structure by adding each
parameter at the highest structure level. Parameter names and string
values are included as JSON strings.
7.2. Client Discovery
The authorization server evaluates this request and MAY perform a
[RFC5785] and [hostmeta] discovery mechanism on the provided URL to
the host-meta document for the client.
For example:
GET /.well-known/host-meta HTTP/1.1
Host: onlinephotogallery.com
The authorization server retrieves the host-meta document, which MUST
contain:
o A "Property" element with a "type" value of
"http://oauth.net/client/name" containing the human-readable
client name. (REQUIRED)
o A "Property" element with a "type" value of
"http://oauth.net/client/description" containing the human
readable description of the client. (REQUIRED)
o A "Link" element with a "rel" value of
"http://oauth.net/client/redirect_uri" (REQUIRED).
o A "Link" element with a "rel" value of
"http://oauth.net/client/uri" (REQUIRED).
o A "Link" element with a "rel" value of
"http://oauth.net/client/icon" (OPTIONAL).
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For example:
<XRD>
<Host>http://onlinephotogallery.com</Host>
<Property type="http://oauth.net/client/name">
Online Photo Gallery
</Property>
<Property type="http://oauth.net/client/description">
Really nice Online Photo Gallery!
</Property>
<Link rel="http://oauth.net/client/uri"
href="http://onlinephotogallery.com">
<Title>Client URI</Title>
</Link>
<Link rel="http://oauth.net/client/redirect_uri"
href="https://onlinephotogallery.com/client_reg">
<Title>Client Redirect URI</Title>
</Link>
<Link rel="http://oauth.net/client/icon"
href="http://onlinephotogallery.com/icon.png">
<Title>Client Icon</Title>
</Link>
</XRD>
7.3. Client Registration Response
After receiving and verifying information retrieved from the client,
the authorization server issues the client identifier and an optional
client secret, and constructs the response by adding the following
parameters to the entity body of the HTTP response with a 200 status
code (OK):
o "client_id" (REQUIRED)
o "client_secret" (OPTIONAL)
The parameters are included in the entity body of the HTTP response
using the "application/json" media type as defined by [JSON]. The
parameters are serialized into a JSON structure by adding each
parameter at the highest structure level. Parameter names and string
values are included as JSON strings.
The authorization server MUST include the HTTP "Cache-Control"
response header field with a value of "no-store" in any response
containing the "client_secret".
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For example the authorization server might return the following
response:
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-store
{
"client_id":"5UO9XcL4TQTa",
"client_secret":"WdRKN3zeTc20"
}
7.4. Error Response
If the request for registration is invalid or unauthorized, the
authorization server constructs the response by adding the following
parameters to the entity body of the HTTP response with a 400 status
code (Bad Request) using the "application/json" media type:
o "error" (REQUIRED). A single error code.
o "error_description" (OPTIONAL). Human-readable text providing
additional information, used to assist in the understanding and
resolution of the error occurred.
o "error_uri" (OPTIONAL). A URI identifying a human-readable web
page with information about the error, used to provide the end-
user with additional information about the error.
An example error response (with line breaks for readability):
HTTP/1.1 400 Bad Request
Content-Type: application/json
Cache-Control: no-store
{
"error": "unauthorized_client",
"description": "This client is not on the
white list of this Authorization Server."
}
If the host-meta discovery was not successful, the authorization
server MUST use the error code "hostmeta_error".
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An example error response (with line breaks for readability):
HTTP/1.1 404 Not Found
Content-Type: application/json
Cache-Control: no-store
{
"error": "hostmeta_error",
"description": "The hostmeta document could
not be retrieved from the URL."
}
8. Native Application Client Registration
For a native application serving as an UMA host, we anticipate that
the need for dynamic client registration to introduce this app to an
UMA authorization manager may typically happen only once (or very
infrequently), likely to a single authorization manager, and
registration could usefully take place at the time the app is
provisioned onto a device. By contrast, for a native app serving as
an UMA requester, it may need to register at multiple authorization
managers over time when seeking access tokens, at moments much later
than the original provisioning of the app onto the device.
When a native application is provisioned on a device, such as through
an app store model, often it has an associated "home base" web server
application component with which it registers (outside of any UMA-
related or OAuth-related interactions). This pairwise relationship
can be exploited in a number of ways to allow trustable, unique
metadata to be conveyed to an OAuth server and for this instance of
the app to receive a client identifier and optional secret. We have
discussed "device-initiated" and "home base-initiated" pattern
options for OAuth dynamic client registration in these circumstances.
Device-initiated flows seem more generically applicable (for example,
for both UMA host and UMA requester needs). However, a home base-
initiated flow may be preferable in case it is necessary to pre-
determine a trust level towards an OAuth server. In this case, the
home base server could initiate the registration process if and only
if there exists a trust relationship between the two parties.
Following is one option for a device-initiated flow:
1. User provisions native app on device and registers with and
authenticates to app's home-base web application.
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2. Home base provisions native app with home base-signed metadata.
3. Whenever user tries to use native app to access a protected
resource, native app provides home base-provided metadata to
server.
4. Server verifies home base signature by pulling public key from
home base URL and generates client identifier and secret for
native app.
5. Server returns client identifier and secret to native app.
9. Security Considerations
Following are some security considerations:
o No client authentication: The server should treat unsigned pushed
client metadata as self-asserted.
o Weak client authentication: The server should treat unsigned
pulled client metadata as self-asserted unless the the domain of
the client matches the client metadata URL and the URL is well-
known and trusted.
o Strong client authentication: The server should treat signed
client metadata (pushed or pulled) and a signed metadata URL as
self-asserted unless it can verify the signature as being from a
trusted source.
10. Acknowledgments
The authors thank the User-Managed Access Work Group participants,
particularly the following, for their input to this document:
o Domenico Catalano
o George Fletcher
o Nat Sakimura
11. Document History
[[ to be removed by RFC editor before publication as an RFC ]]
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12. References
12.1. Normative References
[JSON] Crockford, D., "The application/json Media Type for
JavaScript Object Notation (JSON)", 2006,
<http://tools.ietf.org/html/rfc4627>.
[OAuth-Sig]
Balfanz, D., "OAuth Signature proposals", 2010, <http://
www.ietf.org/mail-archive/web/oauth/current/
msg03893.html>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A., and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999.
[RFC5785] Nottingham, M. and E. Hammer-Lahav, "Defining Well-Known
Uniform Resource Identifiers (URIs)", RFC 5785,
April 2010.
[hostmeta]
Hammer-Lahav, E., "Web Host Metadata", 2010, <http://
xml.resource.org/public/rfc/bibxml3/
reference.I-D.draft-hammer-hostmeta-13.xml>.
12.2. Non-Normative References
[UMA-Core]
Scholz, C., "UMA Requirements", 2010, <http://
kantarainitiative.org/confluence/display/uma/
Working+Drafts>.
[UMA-Reqs]
Maler, E., "UMA Requirements", 2010, <http://
kantarainitiative.org/confluence/display/uma/
UMA+Requirements>.
[UMA-UC] Akram, H., "UMA Explained", 2010, <http://
kantarainitiative.org/confluence/display/uma/
UMA+Scenarios+and+Use+Cases>.
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Authors' Addresses
Thomas Hardjono (editor)
MIT
Phone:
Fax:
Email: hardjono@mit.edu
URI:
Maciej Machulak
Newcastle University
Email: m.p.machulak@ncl.ac.uk
URI: http://ncl.ac.uk/
Eve Maler
XMLgrrl.com
Email: eve@xmlgrrl.com
URI: http://www.xmlgrrl.com
Christian Scholz
COM.lounge GmbH
Phone:
Fax:
Email:
URI:
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