home *** CD-ROM | disk | FTP | other *** search
-
-
- CURRENT_MEETING_REPORT_
-
- Reported by George Clapp/Ameritech and
- Mike Fidler/Ohio State University
-
- MINUTES
-
- The Switched Multi-megabit Data Service (SMDS) Working Group met for the
- first time for a single half-day session on Thursday morning, February
- 8. Co-chair Mike Fidler opened discussion by stating the purpose of the
- group, which is to clarify the manner in which IP may operate over SMDS,
- and then asked George Clapp to present a tutorial discussion of SMDS (a
- copy of the viewgraphs is enclosed with the minutes).
-
- SMDS is a switched, connectionless, high-speed data service which will
- be offered on a nationwide basis by the public carriers. The service is
- intended to be the equivalent of an IEEE 802 LAN in functionality and
- performance and is designed to fit within the internet protocol stack as
- a transit network to IP. First trials may occur in late 1990; the first
- tariffed service may occur in 1991; and the service may be widely
- tariffed and deployed in 1992.
-
- A number of questions arose as George progressed through the SMDS
- tutorial. The first was cost. Members of the group felt that they
- could not evaluate the service until they had an idea of the cost and of
- how that cost compared with the cost of a leased private line. George
- responded that the tariff structure was not yet determined but that the
- public carriers recognized that SMDS must be cost competitive with a
- leased private line. He then queried the group whether they would
- prefer flat or usage-based billing. Members answered that the essential
- feature to billing was predictability and that a flat fee was preferred
- since network administrators had little knowledge or control over the
- traffic generated by their network.
-
- George ended the tutorial by presenting the following list of potential
- topics to be discussed by the working group.
-
- o Addressing and Address Resolution
- o Routing
- o Network Management
-
- With respect to addressing, SMDS uses a 60 bit address similar in format
- to a telephone number. It may be possible to extend ARP to handle the
- 60 bit SMDS address in response to a query for an internet address. The
- notion of ARP itself, however, may be extended to that of a "directory
- service," in which SMDS returns a 60 bit SMDS address in response to a
- network address as well as to an internet address.
-
- With respect to routing, this function may be done in a number of ways
- over SMDS. The routers of an organization may operate as before by
- exchanging link state packets via SMDS to build and maintain routing
-
- 1
-
-
-
-
-
-
- tables. The issue which arises in this approach is the cost of the
- multicast packets, which depends upon the number of routers and upon the
- frequency of the generation of the link state packets. If the cost
- grows too large, alternative approaches may be desirable. One
- alternative may be to use the previously mentioned directory service to
- build the routing table. Rather than exchange link state packets, a
- router may query the directory service for the SMDS address of an
- internet network. The approach, however, would require an extension to
- existing routing protocols.
-
- The discussion of routing brought out two models in which SMDS may
- operate. One is a Private Virtual Network (PVN) in which SMDS
- interconnects a set of routers belonging to an existing organization.
- In this model, communication among devices is restricted to those
- devices which belong to the PVN and communication with devices external
- to the PVN would be carefully controlled. The issues which arise in
- this model are how it would be done and what SMDS features would enhance
- the service. The second model is that of a public network, analogous to
- the existing telephone network, in which an SMDS device may communicate
- with any other SMDS device. The issues which arise here are security
- concerns, such as restricted access and authentication, and the issue of
- scale, since existing algorithms may not operate in an environment with
- large numbers of devices. A third model was suggested in which existing
- leased lines of a private virtual network are kept and SMDS is accessed
- to provide additional capacity.
-
- A number of other questions were raised.
-
- o What will be the performance of SMDS and what are the kinds of
- services that SMDS may adequately support?
- o What kind of network management features will SMDS support? Will
- SMDS "speak SNMP?"
- o How would internet access the proposed directory service?
- o To what extent will SMDS support multicast and how should multicast
- be used? For example, it would be necessary to limit the extent of
- an ARP multicast in the public network model for SMDS, in which
- there is universal connectivity among SMDS devices.
-
- At the end of the meeting, the group tentatively scheduled a video
- conference for either March 27 or 28. (Note: we have subsequently
- learned that these dates are unavailable; new dates are not yet
- determined.)
-
- Mike Fidler had asked those present to indicate on the sign up sheet
- whether they wished to participate in the SMDS mail list. This mail
- list will be built and communication established after the IETF meeting.
-
-
- ATTENDEES
-
- Chet Birger cbirger@bbn.com
- Scott Bradner sob@harvard.harvard.edu
-
- 2
-
-
-
-
-
-
- Mats Brunell mats.brunell@sics.se
- Ted Brunner tob@thumper.bellcore.com
- Steve Casner casner@isi.edu
- Samir Chatterjee samir@nynexst.com
- Steve Crocker crocker@tis.com
- Tom Easterday tom@nisca.ircc.ohio-state.edu
- Kent England kwe@bu.edu
- Dino Farinacci dino@bridge2.3com.com
- Dennis Ferguson dennis@gw.ccie.utoronto.ca
- Dale Finkelson dmf@westie.unl.edu
- Der-Hwa Gan dhg@bridge2.3com.com
- Ella Gardner epg@gateway.mitre.org
- Herve Goguely rvg@bridge2.3com.com
- Steve Goldstein goldstein@note.nsf.gov
- Jack Hahn hahn@umd5.umd.edu
- Gene Hastings hastings@psc.edu
- Juha Heinanen jh@funet.fi
- Chris Hemrick cfh@sabre.bellcore.com
- Bob Hinden hinden@bbn.com
- Steven Hunter hunter@ccc.nmfecc.gov
- Tom Hytry tlh@iwlcs.att.com
- Dan Jordt danj@cac.washington.edu
- Peter Kirstein kirstein@cs.ucl.ac.uk
- Walt Lazear lazear@gateway.mitre.org
- Dan Long long@bbn.com
- Charles Lynn clynn@bbn.com
- Milo Medin medin@nsipo.nasa.gov
- Berlin Moore prepnet@andrew.cmu.edu
- Dennis Morris morrisd@imo-uvax.dca.mil
- Don Morris morris@ucar.edu
- John Moy jmoy@proteon.com
- Dave O'Leary oleary@umd5.umd.edu
- Donald Pace pace@fsu1.cc.fsu.edu
- Guru Parulkar guru@flora.wustl.edu
- Dave Piscitello dave@sabre.bellcore.com
- Dave Pokorney poke@nervm.nerdc.ufl.edu
- Ira Richer richer@vax.darpa.mil
- Jim Showalter gamma@mintaka.dca.mil
- Martha Steenstrup msteenst@bbn.com
- Zaw-Sing Su zsu@tsca.istc.sri.com
- Claudio Topolcic topolcic@bbn.com
- Greg Vaudreuil gvaudre@nri.reston.va.us
- Ross Veach rrv@uiuc.edu
- Steven Willis swillis@wellfleet.com
- Linda Winkler b32357@anlvm.ctd.anl.gov
- Dan Wintringham danw@igloo.osc.edu
- Raj Yavatkar raj@ms.uky.edu
- David Zimmerman dpz@convex.com
-
-
-
- 3
-