Current Meeting Report

2.1.2 Content Distribution Internetworking (cdi)

NOTE: This charter is a snapshot of the 53rd IETF Meeting in Minneapolis, MN USA. It may now be out-of-date. Last Modified: 21-Feb-02
Mark Day <>
Phillip Rzewski <>
Applications Area Director(s):
Ned Freed <>
Patrik Faltstrom <>
Applications Area Advisor:
Patrik Faltstrom <>
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Description of Working Group:
The goal of this working group is to define protocols to allow the interoperation of separately-administered content networks.

A content network is an architecture of network elements, arranged for efficient delivery of digital content. Such content includes, but is not limited to, web pages and images delivered via HTTP, and streaming or continuous media which are controlled by RTSP.

The working group will first define requirements for three modes of content internetworking: interoperation of request-routing systems, interoperation of distribution systems, and interoperation of accounting systems. These requirements are intended to lead to a follow-on effort to define protocols for interoperation of these systems.

In its initial form, the working group is not chartered to deliver those protocols, but we encourage individual submission of internet-drafts describing protocols intended to meet the evolving requirements. We anticipate rechartering of the working group to specify protocols, after the requirements documents are stable and rough consensus emerges about the number and relationship of such protocols.

In addition to defining requirements, the working group will develop a number of supporting documents. These documents are: a shared vocabulary for the problem domain, scenarios, an overall architecture for interoperation, and a summary of request-routing mechanisms currently in use. The total expected deliverables are as follows, including the current draft corresponding to each:

1. Vocabulary

2. Scenarios

3. System Architecture

4. Request-Routing Known Mechanisms n g-04.txt

5. Requirements for Request-Routing x t

6. Requirements for Distribution 2 .txt

7. Requirements for Accounting

In addition to the drafts listed with specific deliverables, the following CDI-related drafts have been written by participants in the group.

Goals and Milestones:
Mar 02   Start WG last call for Scenarios draft.
Mar 02   Start WG last call for System Architecture draft.
Mar 02   Start WG last call for Request-Routing Known Mechanisms.
Mar 02   Start WG last call for Vocabulary draft.
Mar 02   Deadline for new accounting requirements draft or dropping Accounting Requirements from deliverables.
Apr 02   Start WG last call for Request-Routing Requirements draft.
Apr 02   Start WG last call for Distribution Requirements draft.
Jun 02   Vocabulary draft forwarded to IESG by this date for publication as RFC.
Jun 02   System Architecture draft forwarded to IESG by this date for publication as RFC.
Jun 02   Scenarios draft forwarded to IESG by this date for publication as RFC.
Jun 02   Reqest-Routing Known Mechanisms draft forwarded to IESG by this date for publication as RFC.
Jul 02   Request-Routing Requirements draft forwarded to IESG by this date for publication as RFC.
Jul 02   Distribution Requirements draft forwarded to IESG by this date for publication as RFC.
No Request For Comments

Current Meeting Report

Notes for CDI WG meeting on 3/19/2002

Phil Rzewski presented the meeting agenda and introduced the drafts that would be discussed during the meeting. The group is now officially a IETF Working Group the drafts to be discussed were those which had been started in prior BOFs and had been resubmitted as WG drafts.

Mark Day presented the CDI Model draft. There are currently no known issues with this draft, although there is some dependency on the other drafts. The charter has set a milestone of having all non-requirements drafts (including the Model draft) published as RFCs by May 1,2002, so Mark will issue a WG last call on the Model draft as soon as possible.

Phil Rzewski presented the CDI Scenarios draft. Various editor's notes have been resolved. Phil will issue a last call for the draft and intends to followup by submitting as an informational RFC.

The CDI Architecture draft currently does not have an editor so Mark Day requested volunteers. Micheal Speer volunteered to take over as editor for the Architecture draft.

Abbie Barbir presented the Known CN Request Routing mechanisms draft. Known feedback has been incorporated in the draft. Abbie will issue a last call for the draft and intends to submit as an informational RFC.

Brad Cain presented the CDI Request Routing Requirements draft. The only major outstanding issue for this draft is the security section. Brad requested that anyone with input on security requirements send comments on the CDI mailing list. Brad expects to resolve these issues and request a last call before the next IETF meeting.

Lisa Amini presented the CDI Distribution Requirements draft. The Content Signaling portion of the draft have some overlap with the WEBI Resource Update Protocol (RUP) requirments draft. Specifically, RUP defines requirements for managing the consistency of objects that are distributed to surrogates.

Phil Rzewski: Does WEBI have our requirements?
Lisa Amini: Yes, section 5.5.1 of the Distribution draft.
Phil Rzewski: Does the RUP draft reflect our requirements?
Lisa Amini: Not completely, but the document is still being edited.
They intend to cover Inter-CDN and Content Provider-to-CDN consistency, so this would include our requirements for consistency.

Lisa Amini said that the Distribution draft requires additional work on the portions covering streaming media before it could be moved to last call.

Michael Speer: Does it cover RTSP?
Lisa Amini: Yes, but just in terms of MIME type and delivery type (for example, RTSP/RTP).
Lisa Amini: Anyone interested in working on the streaming requirements should see me after the meeting so we can determine if we should hold a special session to discuss in detail. I expect we should be able to request last call before the next meeting.
Mark Day: Actually, it will need to be before then according to the milestones set in the charter.
Lisa Amini: I expect to meet the milestone.

The next topic covered was the CDI AAA draft. Mark Day asked if there were any volunteers to take over the editor role for this draft. Dave Frascone volunteered to take over as editor and expects to be able to complete revisions within the timeline for requirements milestones.

Brad Cain presented a simple architectural proposal for CDI. The presentation included a high level overview of the protocols required for CDI: injecting content into a CN, content replication, consistency maintenance, and advertise topology information for request routing.

Kobus van der Merwe: Don't we also need the ability to advertise capabilities before the distribution request?
Brad Cain: Yes, but I believe, if we wanted to simplify, this could be negotiated offline.

Joseph Hui: Are you aware of UDDI?
Brad Cain: For replication?
Joseph Hui: No, for advertising.
Brad Cain: This may be a good way to go, I will check into it.

Mark Day asked if there were any additional items to be discussed.
There were none so the meeting was concluded.