Last Modified: 2003-10-06
The Open Pluggable Edge Services (OPES) working group is chartered to define a framework and protocols to both authorize and invoke distributed application services while maintaining the network's robustness and end-to-end data integrity. These services may be server-centric (i.e., an administrative domain that includes the origin server) and they may be client-centric (i.e., an administrative domain that includes the user agent).
Services provided in the OPES framework should be traceable by the application endpoints of an OPES-involved transaction, thus helping both service providers and end-users detect and respond to inappropriate behavior by OPES components. In particular, services provided in the OPES framework should be reversible by mutual agreement of the application endpoints. Furthermore, the OPES protocol must include authorization as one if its steps, and this must be by at least one of the of the application-layer endpoints (i.e. either the content provider or the content consumer).
In a first step, this working group will investigate and propose to the Area Directors whether the architecture to be developed must be compatible with the use of end-to-end integrity and encryption. Based on this decision, it will examine the requirements for both authorization and invocation of application services inside the network. The group will create an architecture for OPES services applied to application messages, and specify the protocol for HTTP and RTP/RTSP. The working group will define one or more methods for specification of policies, as well as the rules that enable application endpoints to control execution of such services.
The working group will have a design goal that policies affecting the control and authorization rules be compatible with existing policy work within the IETF (e.g. IETF Policy Framework) and be able to interface with systems automating distribution of policies to multiple endpoints, but it will be out of scope for this work to develop the policy framework and specify multiple-endpoint policy distribution.
With the requirements, the working group will specify a protocol or suite of protocols for invocation and tracking of OPES services inside the net, including the authorization and enforcement elements for one endpoint.
The working group will consider the ICAP protocol drafts as an OPES precursor and will will support development of an analysis that explains the limitations of ICAP, to accompany informational publication of that protocol. The working group will coordinate with other groups such as AVT and MMUSIC (in regard to RTP/RTSP) and WEBI (in regard to HTTP).
The group's work items can be listed as:
- Develop scenarios and use case document.
- Draft high-level, overall example OPES architecture.
- Define requirements for service invocation and tracing (callout).
- Define policy specification method(s) and rules for controlling execution of OPES services.
- Define callout and tracing protocol(s).
- Develop a vulnerability assessment and use this to guide each type of security service to be included in the protocols developed.
As each deliverable is developed, it must address the IAB considerations specified in RFC 3238.
- OPES scenarios and use case document.
- General OPES architecture/framework.
- Requirements for authorization and enforcement of OPES services.
- Requirements for invocation and tracking of OPES services.
- Vulnerability assessment document for OPES services.
- Mechanisms and protocols for service invocation and service tracking.
|Done||Submit OPES scenarios document and architecture document to IESG for Informational.|
|Done||Submit document on protocol (callout and tracing) requirements to IESG for Informational.|
|Done||Submit document on endpoint authorization and enforcement requirements to IESG for Informational.|
|Done||Submit document on threat/risk model for OPES services to IESG for Informational.|
|Done||Initial protocol document for OPES services including their authorization, invocation, tracking, and enforcement of authorization.|
|Done||Initial document on rules specification method.|
|Sep 03||Submit protocol document for OPES services including their authorization, invocation, tracking, and enforcement of authorization to IESG for Proposed Standard.|
|Oct 03||Submit document on rules specification method to IESG for Proposed Standard.|
|Oct 03||Consider additional OPES work such as extension to traffic beyond HTTP and RTSP and present new charter to IESG, or conclude working group.|
Open Pluggable Edge Services (OPES) 58th IETF Meeting 11 November 2003 Eric Burger, scribe Jabber log is at <http://www.xmpp.org/ietf-logs/opes@iet f.xmpp.org/2003-11-11.html> ===== Agenda Bashing: Markus Hofmann ===== Document Status - See slides & ID Tracker Goal: finish documents in "ID Exists" status by end of November ===== OPES Treatment of IAB Considerations draft-ietf-opes-iab-03 - Abbie Barbir See slides On Considerations 3.1 & 3.2: chose to make notifications optional; focus on tracing. Clearly, OPES cannot do end-to-end encryption. OPES can do hop-by-hop encryption. Sally Floyd: Likes document; addresses IAB issues Markus: expect WGLC soon after IETF ===== OPES process and end points communications Draft-ietf-opes-end-comm-05 - Abbie Barbir See slides Tracing ------- Open issue: What is OPES Tracing? Current wording has problem with "inclusion". Does that mean that trace can be adapted (pruned, modified, added-to)? Should we allow trace adaptation? Trace information designed for system administrators, not users. Bypass ------ IAB Considerations said to bypass non-OPES content. But, what is OPES content? Solution: punt -- definition of OPES content is outside scope of OPES. Sally Floyd: Comment: IAB document isn't legal language. Try to figure out what the intent is. The IAB document does not mean "user has to have a way to bypass firewalls, boundaries, etc." It is saying, "If a user asks for content from web server, and the content gets mangled by an OPES server, then user needs to be able to figure out what went wrong." MUST/SHOULD/MAY questions: see slides w.r.t. OPES bypass - Sally Floyd: Source of IAB concern about non-OPES is data integrity, e.g., how does one detect malicious transformation of data. ===== OPC: OPES Callout Protocol draft-ietf-opes-ocp-core-03 - Abbie Barbir see slides Should authentication be in the core or binding (HTTP)? Should authentication be in this draft, or a separate draft? Same issues for Encryption. Should we get IETF review before going to WGLC? Marshall: "NO" Application message identifiers are irrelevant for HTTP, but might not be robust enough for SMTP. Should we dump them and figure out the right thing for SMTP later, if there is a later? Markus: Please post comments on AM-ID's to the list! ===== HTTP Adaptation with OPES Draft-ietf-opes-http-01 (from Martin and Alex) presented by Markus See slides Targeting WGLC for end of November Need HTTP expert to review HTTP-specific issues, and in particular on HTTP-specific security considerations Open issues: How to avoid blocking; skip uninteresting request bodies in 'response mode'; and handle HTTP-specific things like 100 Continue and 206 Partial Content? Please check for XXX's in document and send text to mail list! ===== P: Message Processing Language Presented by Markus See slides Open issues: What information is available to interpreter? Complete message? Headers only? Punt? Is doing HTTP module in scope for work group? If so, in what document? Should work group define interfaces between P interpreters and module suppliers or callout services? If so, how do services return results, e.g., from OCP? Ted Hardie: Working group should specify what information is available to the interpreter. Not a value judgement of where, just we should set expectations for community. Ted Hardie: When do we expect the current charter items to be done? Markus: Hopefully December. ===== OPES Future Markus Note: Re-chartering is ONLY for adding new work items, not for staying alive to do work from old charter. Keep new work in OPES framework, not something new. Really need to know who will be committed to working on new work items. PLEASE POST THOUGHTS AND SUGGESTIONS TO MAIL LIST. PLEASE VOLUNTEER TO DO WORK!!! OPES for SMTP and IMAP: does it conflict with lemonade? Eric Burger: Not at all. Definitely fits into OPES, just need to coordinate groups. If you have interest in a topic, want to be an editor or contributor, please post to list. Marshall: Importance of finishing documents -- "credibility is the coin of the realm."