Internet Info 1997 December/Internet_Info_CD-ROM_Walnut_Creek_December_1997.iso/ietf/ospf/ospf-minutes-93mar.txt

Text File | 1993-04-30 | 8.3 KB | 203 lines

CURRENT_MEETING_REPORT_


Reported by John Moy/Proteon

Minutes of the Open Shortest Path First IGP Working Group (OSPF)

The OSPF Working Group met on Tuesday, March 30th at the Columbus, IETF.
The Minutes of that meeting follow.  The meeting began with a discussion
of the six documents that the Working Group had in progress:


  1. The latest draft of the OSPF V2 specification was reviewed.  The
     only change that had been made since the last meeting was to handle
     the following case:  A router becomes Designated Router, originates
     a network-LSA, then later restarts with a different Router ID and
     becomes Designated Router again.  At this point, the router
     originates a network-LSA having the same Link State ID, but
     different Advertising Router, than the previous network-LSA. The
     fact that these two network- LSAs can both exist in the OSPF domain
     concurrently can confuse the Dijkstra calculation.  Text has been
     added to the specification ensuring that the network-LSA originated
     before the last router restart will be flushed.
     After some discussion, it was decided to submit the latest draft
     (which had been published as an Internet-Draft) to replace RFC1247
     at the current standards status (Draft Standard).

  2. The OSPF Trap MIB had remained unchanged, except for editorial
     comments, since the last meeting.  It was decided to submit this to
     be published as a Proposed Standard RFC.

  3. The OSPF NSSA area specification was reviewed.  A problem was found
     in the aggregation of multiple type 7 LSAs into a single type 5
     LSA, involving the choice of metric.  Two solutions were discussed:

       o Have the type 7 LSAs always take precedence, and
       o Set the metric to be the largest of any of the component
         metrics.  Rob Coltun will investigate these options further.


  4. Osmund deSouza presented a document describing how to run OSPF over
     Frame Relay.  The document describes how to split the Frame relay
     PVCs into collections of OSPF Point-to-point networks and NBMA
     networks.  A comment was made that treating PVCs as unnumbered
     links was problematic, due to the inability to assign an ifIndex to
     individual PVCs.  It was decided that after adding comments, the
     document will be submitted for publication as an Informational RFC.

  5. No progress had been made on the OSPF MIB, which needs some
     additions before it can be republished.

  6. No progress had been made on the ``OSPF Database Over-flow''

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     document.


The ``OSPF for SIP'' Internet-Draft written by Christian Huitema was
summarized as:  regular OSPF, running over IPv4, with two additional
LSAs to import SIP information and an additional bit in the router-LSA
to indicate SIP capability.  This was intended to allow a more or less
seamless migration from IPv4 to SIP, after which a native OSPF for SIP
would be defined.  Detailed discussion of the Draft was carried on in
the SIP Working Group.  In fact, it was decided that all detailed
discussions of OSPF in IPv7 would be carried on in the appropriate IPv7
working groups.

Dennis Ferguson then presented an overview of his ``OSPF external
attributes'' proposal, which is an addition to the OSPF<->BGP routing
interchange and can be used as a substitute for Internal BGP. Dennis
also presented operational statistics from the NSFnet that indicated his
proposal would be quite efficient.  Discussion indicated that
efficiency, measured in terms of the percentage of the database
dedicated to this scheme, would decrease when CIDR was deployed.  Tony
Li mentioned that it will also be necessary to know whether all routers
participating in the ``OSPF external attributes'' are BGP-4 speakers, or
whether some are BGP-3 speakers, in order to decide whether BGP
aggregation should be done.  Most of the discussion then centered on the
problem that, since the external attributes (type 8 LSAs) can only be
flooded through supporting OSPF routers, it is possible that the
database of external attributes could get out of synch with the type-5
LSAs (which in turn could lead to problems in BGP routing).  Dennis
suggested three ways of dealing with this:


  1. Choose the Link State IDs for type 8 LSAs in a random fashion, so
     that lack of synchronization would be obvious.

  2. Potentially run Dijkstra a second time to ensure that there is
     type-8 flooding connectivity between BGP speakers, or

  3. Change the document so that ``most'' routers must be capable of
     flooding type 8 LSAs.  No decision was made on these options.
     Finally, it was noted that a combination of Internal BGP and the
     new ``OSPF external attributes'' cannot be run since the tag field
     in the OSPF type 5 LSAs would then have two conflicting
     requirements.


Tom Pusateri presented an outline of a proposed RIP to OSPF transition
document, based on a talk he gave at INTEROP. He solicited suggestions
for additional items to cover (send to [e-mail]).
Suggestions given at the meeting were:


  1. Warning against running OSPF and RIP in parallel.
  2. Give an example of a real, non-trivial network and how to

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     transition it.
  3. How to do address assignment.
  4. How to decide what's in an area.


Lastly, a conflict between OSPF and Router Requirements was mentioned.
Router Requirements states that you can't follow the default route to
get to subnets.  This rule doesn't work for OSPF stub areas, and several
people mentioned that the rule, while consistent with RIP, shouldn't
really apply to other protocols.  A different rule, along the lines of:
``when aggregating, create a discard route for the aggregate'', was
suggested.  Philip Almquist, the editor of the Router Requirements
documents, was present and participated in the discussion.

Attendees

Philip Almquist          [e-mail]
Dennis Baker             [e-mail]
Fred Baker               [e-mail]
Jim Beers                [e-mail]
Nutan Behki              [e-mail]
Richard Bjers            [e-mail]
John Boatright           [e-mail]
Robert Calderon          [e-mail]
Douglas Carson           [e-mail]
James Cassell            [e-mail]
Rob Coltun               [e-mail]
David Conrad             [e-mail]
Wayne Cullen             [e-mail]
Kurt Dobbins             [e-mail]
Kishan Dudkikar          [e-mail]
Dennis Ferguson          [e-mail]
Paul Franchois           [e-mail]
Christine Fredenburg     [e-mail]
Vince Fuller             [e-mail]
Darren Griffiths         [e-mail]
Patrick Hanel            [e-mail]
Jeffrey Honig            [e-mail]
David Jacobson           [e-mail]
Zbigniew Kielczewski     [e-mail]
John Krawczyk            [e-mail]
Duane Kuang              [e-mail]
Tony Li                  [e-mail]
Robin Littlefield        [e-mail]
Glenn Mackintosh         [e-mail]
Jamshid Mahdavi          [e-mail]
Glenn Mansfield          [e-mail]
Jun Matsukata            [e-mail]
James Miner              [e-mail]
John Moy                 [e-mail]
Julie Myers              [e-mail]
Shannon Nix              [e-mail]
Zbigniew Opalka          [e-mail]

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Ayal Opher               [e-mail]
Joe Pagan                [e-mail]
Thomas Pusateri          [e-mail]
Edward Reed              [e-mail]
Ben Robinson             [e-mail]
Benny Rodrig             [e-mail]
Manoel Rodrigues         [e-mail]
Hal Sandick              [e-mail]
Shiva Sawant             [e-mail]
Kanan Shah               [e-mail]
Andrew Smith             [e-mail]
Martha Steenstrup        [e-mail]
Steve Suzuki             [e-mail]
John Tavs                [e-mail]
Marek Tomaszewski        [e-mail]
Kannan Varadhan          [e-mail]
Linda Winkler            [e-mail]
Jane Wojcik              [e-mail]



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