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Re: Revised Charter for BOF Discussion and Concensus

2001-03-06 15:20:12

Maybe this a focus of a different group. Being a transit intermediary
(i.e. a "middle" box in the datapath from end to end) is the service
center. It need not be a cache. The rule system under discussion
may work for our end architecture or not - depending on consensus.
If the rule system works for other environments, that's great.

How does your goals fit with rserpool?

Do I mis-understand your objectives?

At 04:21 PM 3/6/2001 -0500, you wrote:

My concern is that the rule framework being devised is being scoped too
narrowly, specifically to "services executed on application data by
participating transit intermediaries."   I am interested in using this rule
language for services executed on non-caching replica servers that may not
be transit intermediaries (unless I'm not understanding the meaning of
transit intermediaries).  If the charter does not reflect the additional
goal of devising a rule language usable for both caches and replica servers
that are not caches, then the specification coming out of this group may not
be adequate to that purpose.  Which would mean that we would need to have
another, perhaps very similar, rule language for specifying "services
executed on application data by participating replica servers."

The fundamental difference between the rules for caches and the rules for
replica servers is the API of the proxylets/servelets invoked by those
rules.  Aside from this difference, I am quite sure that a single rule
language can suffice for both purposes, but not if the design criteria for
that language are drawn too narrowly.


----- Original Message -----
From: "Michael W. Condry" <condry(_at_)intel(_dot_)com>
To: <ietf-openproxy(_at_)imc(_dot_)org>
Cc: <paf(_at_)cisco(_dot_)com>; <ned(_dot_)freed(_at_)innosoft(_dot_)com>
Sent: Tuesday, March 06, 2001 3:51 PM
Subject: Revised Charter for BOF Discussion and Concensus

> Mail discussions and our workshop suggested that the initial focus
> of the working group should be organization of requirements for the
> overall OPES architecture and delivery of specific solutions, such as
> callout service protocols. With this in mind Hilarie and I have revised
> charter to reflect this need, assuring we are working on an industry
> plan and havedistinguished goals from MidCom, CDI, MidTax, etc.
> Here is the revised charter:
> Orthogonal Protocol Extension Services(opes)
> Co-chairs:
>     Michael Condry <condry(_at_)intel(_dot_)com>
>     Hilarie Orman <HORMAN(_at_)novell(_dot_)com>
> Mailing Lists:
>     General Discussion: ietf-openproxy(_at_)imc(_dot_)org
>     To Subscribe: ietf-openproxy-request(_at_)imc(_dot_)org
>     Web:
>     Archive:
> Description of Working Group:
> The Orthogonal Protocol Extension Services architecture (OPES) enables
> construction of services executed on application data by participating
> transit intermediaries.  Caching is the most basic intermediary service,
> one that requires a basic understanding of application semantics by the
> cache server.  Because intermediaries divert data temporarily over a
> pathway different from the transit pathway, one can think of the service
> path as being orthogonal to the main transit path.  The purpose of this
> working group is to define the protocols and API's for a broad set of
> services that facilitate efficient delivery of complex content or services
> related to content.  The advantage of standardizing these protocols and
> API's is that the services can be re-used across vendor products without
> modifying the transit intermediaries or services.
> The architecture supports services that are either co-located with the
> transit intermediary or located on other servers (referred to as auxiliary
> servers in this charter).  The ICAP protocol is being developed for
> carrying HTTP headers and data to cooperating servers; other protocols for
> carrying SMTP or other protocols to cooperating servers will be supported
> by the framework, as they exist or become available.  This working group
> defines the supporting configuration data and protocols for configuring
> services on the transit intermediaries; this configuration makes it
> possible to administer collections of transit intermediaries and content
> services as a coherent system.
> There are four parts of a good service definition for transit-based
> extensions to an application protocol.  The first part defines the
> processing point or points in the intermediary that could detect an
> application data event of interest to the auxiliary service.  The second
> part defines the server, the access method for the server, and the
> marshaled form for arguments added when delivering the application data to
> the auxiliary server.  The third defines the post processing of the data
> returned by the auxiliary.  The fourth element of the definition is an
> encoding of the above information combined with the service extension
> itself, defined as some form of loadable code or access method for
> the code.  The working group will define an information model and
> realization of the model into repository and protocol elements.
> These service definitions must be standardized in ways that are compatible
> with the policy framework of the Policy working group. The definitions
> constitute configuration information that can come from repositories or
> runtime protocols; for example, and ICAP server coming on-line can notify
> its clients of the services it offers, and it can update their status
> ("up", "changed", "suspended", "moved") while it is running.  A namespace
> for services and a means for registering names will be considered.
> Some crucial data must be communicated from the intermediary to the
> auxiliary server in standardized semantics.  Identification and
> authentication information for the application connection may be important
> to the auxiliary processing, for example.  The working group will define a
> core set of information necessary for supporting generic application
> Postprocessing the result from the auxiliary processor is done at the
> option of the intermediary, but instructions from the auxiliary server
> be communicated in a standardized manner.  Generic directives ("drop",
> "hold", "assign attribute", are examples.  The working group will define
> postprocessing directives and the rules for their interaction with the
> configuration policy.
> The security model for intermediary services involves defining the
> administrator roles and privileges for the application client, application
> server, intermediary, and auxiliary server.  The working group will use
> Policy Configuration Information Model to define the security attributes
> and the enforceable policy.
> The working group items for delivery are
> 1.      A "side transit" protocol (ICAP) for use with HTTP
> 2.      A policy-based configuration and definition model for orthogonal
> service extensions
> a.      To include representation of conditions leading to invocation of
> extension services, common data items (identities, authentication state,
> etc.), postprocessing directives, and the access method for the service or
> a representation of a loadable service (URL or encoded executable or
> interpretable code, for example).
> b.      A specific repository-based embodiment of the model
> c.      A delivery protocol embodying the elements of the model as a
> language; the protocol may be embedded in HTTP and/or ICAP.
> d.      Recommended procedures for registering service names and
> repositories for extensions
> 3.      A security model and security configuration policy definitions,
> i.e. roles, privileges, and enforcement point responsibilities.
> After these items have been delivered, the working group can examine the
> progress in this area and, if appropriate, re-charter to with more
> general work items in the OPES framework.
> Existing Internet-Drafts
> Basic Requirements:
>          http://draft-tomlinson-epsfw-00.txt
> Initial iCAP Callout Server:
>          http://draft-elson-opes-icap-00.txt
> A Rule Specification Language for Proxy Services:
>          http://draft-beck-opes-psrl-00.txt
> General Use Cases:
>          http://draft-beck-opes-esfnep-01.txt
> Goals and Milestones:
> Feb 01: Requirements and roadmap documents for WG
> Feb 01: First draft of HTTP orthogonal protocol; first draft of policy
> information model
> Mar 01: Meet at Minneapolis IETF
> Mar 01: OPES architecture and requirements documents
> Jun 01: Submission of security model and configuration policy to IETF
> Jul 15: Draft of policy rules, enforcement semantics, standard data items,
> and post processing
> Aug 01: Meet at London IETF
> Aug 01: Final submission of HTTP orthogonal protocol.
> Oct 01: Submission of repository specific and ICAP-based policy rule
> deliver protocol
> Dec 01: Salt Lake City IETF.
> Dec 01: Review charter, if necessary, amend for additional orthogonal
> protocol definitions, standard data items, postprocessing directives.
> Michael W. Condry
> Director, Network Edge Technology

Michael W. Condry
Director, Network Edge Technology