Subject: WG Review: Open Pluggable Edge Services (opes)

From: The IESG <[email-masked]>
Date: Mon, 02 Jul 2001 18:04:26 -0400

A new IETF working group has been proposed in the Applications Area.
The IESG has not made any determination as yet. Note that this is the
second review message for OPES due to changes to the original
proposed charter.

The following Description was submitted, and is provided for
informational purposes only:

Description of Working Group:
 
The Internet is facilitating multiple forms of distributed
applications, some of which employ application-level intermediaries.
The Open Pluggable Edge Services (OPES) working group's primary task is 
to define application-level protocols enabling such intermediaries to 
incorporate services that operate on messages transported by HTTP and 
RTP/RTSP. At the IP level, the participating intermediaries are 
endpoints that are addressed explicitly.

The protocols to be defined provide a framework for integrating a wide
range of services into application-level intermediaries. The advantage 
of standardizing such protocols is that services can be re-used across 
vendor products without modifying the intermediaries or services.

Intermediary services provided in this way are not transparent: They 
must be authorized by the application endpoint (either the content 
requestor or the content provider) that requests the intermediary 
service. A key task for the working group is to specify an appropriate 
authorization mechanism.

Intermediaries may employ services executed either locally or on a 
remote ("callout") server. One task for this working group is the 
development of callout protocols that enable the receiving callout 
service to either receive encapsulated HTTP or RTP/RTSP messages or, 
through some other mechanism, for the callout service to receive the 
application data necessary to perform its services.

The iCAP protocol provides similar function for services operating on
iCAP-encapsulated HTTP application data. The working group will
evaluate the iCAP protocol as one candidate for passing HTTP
application data for remote services. It may decide to extend or even 
not use the iCAP protocol without being obliged to retain any level of 
compatibility with the current iCAP proposal.

Another task for this working group is to enumerate the requirements
for management policies and associated administrative protocols that 
allow these services to be specified and deployed. This includes 
requirements on the rule systems used to specify conditions under which 
services are executed.

The working group will develop a security model for OPES services in 
which authorization and enforcement will be defined. The model will 
specify the entities, privileges, notifications, and authorization 
actions affecting content. In addition, the model will show how 
end-to-end services and data integrity concepts are mapped onto the
OPES architecture.

Related Internet-Drafts

Prior related requirements document (expired but available on the web 
site):
  draft-tomlinson-epsfw-00.txt

Updated iCAP Callout Protocol:
  draft-elson-opes-icap-01.txt

A Rule Specification Language for Proxy Services:
  draft-beck-opes-irml-00.txt

OPES Network Taxonomy:
  draft-erikson-opes-net-taxonomy-00.txt

OPES Architecture for Rule Processing and Service Execution:
  draft-yang-opes-rule-processing-service-execution-00.txt

OMML: OPES Meta-data Markup Language:
  draft-maciocco-opes-omml-00.txt

General Use Cases:
  draft-beck-opes-esfnep-01.txt