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-
-
- J. Postel
- IEN 134 ISI
- 29 February 1980
-
-
-
- Internet Meeting Notes - 4, 5, & 6 February 1980
-
-
-
-
- I. INTRODUCTION - Kunzelman, Shoch
-
- This meeting was held at SRI on Monday and Wednesday and at XEROX
- PARC on Tuesday. Ron Kunzelman was the coordinator at SRI, and John
- Shoch was the coordinator at XEROX.
-
- II. OVERVIEW AND OBJECTIVES - Cerf
-
- Vint briefly restated the current issues of concern in the internet
- program. The principal issue is now performance. The Fort Bragg
- users and the european users depend on the internet for access to
- their host computers.
-
- III. STATUS REPORTS
-
- A. DARPA - Cerf
-
- Vint reported that ARPA as a whole had been reorganized to better
- balance the various offices. IPTO itself had not been affected.
- Vint noted that in the last few years IPTO had put more emphasis
- on test beds and demonstration projects to promote technology
- transfer, and that this had hurt basic research. Vint thinks that
- there will be an increase in support for research.
-
- Vint reported that the protocol standardization effort in DOD is
- moving forward, and that IP and TCP as documented in IENs 128 and
- 129 form the basis for the standards.
-
- Vint repeated his desire for each contractor to identify
- milestones and to make monthly progress reports. Jon Postel will
- coordinate these reports.
-
- B. BBN - Plummer, Strazisar, Haverty, Wingfield, McNeill, Brescia,
- Flood Page, Nelson
-
- Bill reported that TCP and IP on TOPS 20 are working and that he
- is begining work on the Tenex versions. For this he is using a
- new host at BBNG. The XNET program has been converted. FTP on
- TCP is in the queue but not top priority.
-
-
-
-
- Postel [Page 1]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- Ginny reported that all gateways but one have been converted to
- MOS based systems, and that conversion of the bootstraps and
- loaders to use IP is in progress. The gateways do participate
- with the CMCC by sending the monitoring reports. A port expander
- has arrived at BBN.
-
- Jack reported on the development of XNET programs in the UNIX
- environment. The Unix debugger has been extended to allow
- debugging of processes on another machine via XNET. Two XNET
- servers have been created, one for debugging at the system level,
- and another for debugging at the process level.
-
- Jack also discussed the problems with connecting things via 1822
- style interfaces. The problems arise because the available
- specification is for a host side interface, and the host side is
- allowed to be sloppy about its signals while the IMP side is not.
- Plugging two host side interfaces together sometimes doesn't work
- due to differences in signal levels allowed by the host side
- specification. If these interfaces were built to the more
- stringent (and undocumented) IMP side specification these problems
- could be avoided. ACTION: Vint will investigate provision of
- 1822 interfaces that meet IMP side specification.
-
- Jack noted that BBN is implementing IP and TCP for an HP3000 data
- management system for ARPA.
-
- Mike Wingfield reported that the "C" version of the unix IP and
- TCP will be used for both the ARPA Internet and AUTODIN II
- environments, and the macro version will be phased out. MOS2 has
- been rewritten in "C." The TCP has been studied for performance
- bottlenecks, with the current suspicion falling on the
- interprocess communication facility. Fragmentation and reassembly
- are being added to TCP. The AUTODIN II FTP is being implemented.
-
- Dale reported that SATNET is working well except for a 5 day
- period where there were hardware problems at Goonhilly. SATNET
- continues to support ARPANET traffic to/from Europe via "line 77."
- Performance between the channel protocol modules has been
- measured. A gateway between MATNET (a secure shipboard SATNET)
- and a secure subset of the ARPANET will come into existence.
-
- Mike Brescia discussed gateway operation and monitoring
- operations. An NCC style gateway monitoring center is being
- setup. A gateway is being developed for connecting the ARPANET
- and an X.25 net. The X.25 side is still under development.
-
- David briefly mentioned the status of the Catenet monitoring
- programs. These are discussed in another session of the meeting.
-
-
-
- Postel [Page 2]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- Ruth reported on the development of a local net for the ACCAT
- testbed at NOSC. There will be a gateway to the secure subset of
- the ARPANET. An MBB Unix will be used. This work is in the
- design stage. IP and TCP will be used in the local network, which
- uses an 8 megabit base band cable with collision detection. This
- is based on the MIT CHAOS net experience.
-
- C. DCA - Cain
-
- Ed reported that the local net which has operated for several
- years based on an old version of the ARPANET IMPs will now have to
- be brought up to date to use 96 bit leaders so this net can
- participate in experiments with BCRs.
-
- D. COMSAT - Mills
-
- Dave reported that work continues on the PSP and NET, however the
- main effort in recent months has been the demonstration for the
- NTC. The "demo" system has been configured to run on a variety of
- PDP-11 models. In the process of preparing for the demo some
- performance problems were detected, and since the demo some study
- has been done to isolate them (more on this in a later session).
- These performance issues also prompted some tuning of parameters
- and strategy in the MOS TCP. On another front Dave found a way to
- decode compressed FAX files. Dave has several written reports
- giving more detail on the work of COMSAT.
-
- E. DOD - McFarland
-
- Ray reported that Ken Shotting is attempting a formal
- specification of IP in SPECIAL, and may be ready to give a report
- at the next meeting.
-
- F. ISI - Postel
-
- Jon noted that ISI is working in three task areas: (1) Protocol
- Development, which includes the work on IP and TCP specifications;
- (2) Internet Mail, which includes development of mechanisms for
- delivery of mail in an internet and provision for multi-media data
- in the mail; and (3) protocol verification, which aims at the
- analysis of IP and TCP for correct operation.
-
- G. Linkabit - Hoversten
-
- Estil noted Linkabit's involvement in SATNET and the WBC
- experiment, and his participation in the development of the ST
- protocol. Estil claimed to be the advocate of wild ideas. [Danny
-
-
-
-
- Postel [Page 3]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- Cohen immediately claimed to be the advocate of tame ideas.]
- Linkabit is also considering a set of local networks.
-
- H. LL - Forgie
-
- Jim reported on efforts to make the SATNET voice conferencing more
- robust. Dale McNeill helped by fine tuning the SATNET but there
- were still problems in the overall path. It seems that the ELF
- based gateway introduces too much delay into the system. The idea
- of a film on SATNET conferencing has been canceled due to the poor
- performance of the system. There appears to be no further need
- for the ELF gateway in SATNET.
-
- Jim also briefly mentioned the status of the ST protocol, which
- will be reviewed in a later session. Jim did discuss the WBC
- experiment and indicated the goals of having the LL, ISI, and SRI
- sites up for point-to-point packet voice by September 1980, and
- multiplexing of cells through a Voice Funnel by September 1981.
-
- I. MIT - Clark
-
- Dave noted that version 1 of the LCSNET is in operation with a PDP
- 11 Unix system and a VAX connected, and the MIT-XX TOPS 20 to be
- connected in April. Version 2 of the LCSNET is being debugged.
- Version 2 operates the cable at 8 megabits (version 1 operates at
- 1 megabit).
-
- Dave described the development of a personal terminal to be built
- for LCS by Zenith. The prototype was built by Steve Ward at MIT.
- LCS expects to have 10 of these by the end of May, 40 by the end
- of 1980 and 150 by the end of 1981. These personal computers will
- interface directly to the LCSNET.
-
- Dave also reported continuing problems with the port expander and
- ARPANET hosts. A testing session will be set up at BBN involving
- people from BBN and SRI. ACTION: Ron Kunzelman and Bill Plummer
- will test port expander with BBNF.
-
- Dave also noted that MIT received a gift of 20 Altos and an
- ethernet from XEROX, and that some effort will be needed to
- integrate them into the environment. A common Trivial FTP is in
- progress, the plan is to develop IP, TCP, and Telnet for the
- Altos.
-
- There will be an improved Telnet server on Multics soon, and a
- mail queuer for local net users. IP reassembly code will be
- added.
-
-
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- Postel [Page 4]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- Dave did not prepare a memo for this meeting on congestion
- control, but expects to have a presentation on the topic for the
- next meeting.
-
- J. NDRE - Lundh
-
- Yngvar reported that the plans of NDRE are quite behind schedule
- due to lack of staff. The problems with the VDH connection have
- been solved and TCP is working. NDRE is developing a local net
- involving NORD-10 and NORD-100 computers.
-
- K. RSRE - Davies
-
- Brian reported on the development of the RSRE gateway and the
- experiences with the gateway-gateway protocol and CMCC monitoring
- protocol. Things seem to work well except for a few special
- cases. For example, when a "tail" gateway crashes it takes many
- gateway routing update steps to get the hop count up to
- "infinity." The temporary fix is to use a smaller value for
- "infinity" (today "infinity" = 5).
-
- Another problem is that the host routing in TOPS 20s does not
- switch to the NDRE gateway when the BBN gateway is down. ACTION:
- Bill Plummer to change TOPS 20 host routing procedures, Vint Cerf
- to get the priority for this task.
-
- RSRE has also experienced problems using TCP between RSRE and
- ISIE. There may be a data stream capture problem. Even when all
- is going well there are many duplicates, seemingly due to the
- round trip time being longer than the TOPS 20 TCP retransmission
- timeout. Brian estimates the delay at six (6) seconds.
-
- RSRE will be working on a connection to PSS and a new X.25-TCP
- interconnection.
-
- L. SRI - Kunzelman, Cone, Nelson, Frankel
-
- Ron discussed the status of the TIU, and reported that it is now
- fully converted to IP and TCP. The PRNET at SRI has been
- converted to the CAP5 protocol. A PDP-11/44 will be installed as
- a PRNET measurement facility.
-
- Don reported that six port expanders have been delivered and that
- five more are in the works.
-
- Holly discussed the state of the port expander software.
-
- Mike discussed the Ft. Bragg PRNET status. Six radio units are
-
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- Postel [Page 5]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- installed. There are problems of response delays to the users
- from Ft. Bragg to ISIE. There may be a data stream capture
- problem. The gateway seems to be a thruput bottleneck.
-
- Raphi reported on a local network development at SRI. This will
- be based on XEROX Ethernet PDP-11 interface boards. These come
- from XEROX with a unibus interface, SRI will convert them to Qbus
- interface to be able to use LSI-11s to front end the host systems.
- The hosts will be the TOPS20, Unix, B6700 systems now at SRI. The
- first service will be computer mail based on the Deleware MMDF and
- the SRI Deafnet. Telex and TWX will also be connected into the
- online mail system.
-
- M. UCL - Jones
-
- Ron discussed the UCL involvement in the NTC demonstrations, and
- in the RSRE interconnection to the internet. Several tasks were
- delayed due to the development machine being out of service for 6
- weeks. An ARPANET/PSS gateway is under development. This will be
- a protocol translation gateway converting between X.25 and TCP and
- eventually up to the Telnet protocol level. Experiments are
- beginning with a connection to IPSS. An NCP/TCP gateway was
- demonstrated on ISIE. The NIFTP now runs on both ISIE and UCL
- Unix. UCL has also been active with the development of a FAX
- protocol. The UCL local net (a cambridge ring) now has 5
- stations. It is planned to use TCP as the protocol above the ring
- driver.
-
- N. MITRE - Skelton
-
- Anita reported that the local net (a cable bus) is up and running.
- There is work to upgrade the BIUs to allow larger packets and
- higher data rates on the net. A second net is to be installed at
- DCEC. There is also work to create an X.25 BIU interface.
-
- O. UCLA - Braden
-
- Bob reported that the machine at UCLA-CCN is now a 3033 running
- OS/MVT. IP and TCP are up, and a server telnet is in place.
-
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- Postel [Page 6]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- IV. DOCUMENT STATUS - Postel
-
- Jon reported that the following documents were issued since the last
- meeting:
-
- IEN 120 by Radia Perlman on "Internet Routing and the Network Portion
- Problem."
-
- This memo discusses ways in which gateway routing data could be
- used to overcome the problems of partitioned networks.
-
- IEN 121 by Postel on "Internet Meeting Notes - 10, 11, 12, 13
- September 1979."
-
- This is simply the notes of the last meeting.
-
- IEN 122 by Cohen on "Addressing and Related Issues (or Fuel for a
- Discussion)."
-
- A suggestion that not all local networks need to be registered as
- full networks in the internet and some ways of addressing the
- hosts on such unregistered networks.
-
- IEN 123 and 124 were the December versions of the IP and TCP
- specifications. These were the first try at the DOD Standard
- versions.
-
- IEN 125 by Cerf on "Pre-emption."
-
- This is a note detailing how pre-emption can be handled at the
- application level.
-
- IEN 126 by Cohen on a "Summary of the ARPA/ETHERNET Community
- Meeting."
-
- This describes a plan for the co-existence of the PUP internet and
- the ARPA internet protocols.
-
- IEN 127 by Postel on "Assigned Numbers."
-
- This is the latest edition of the list of network, protocols,
- ports socket, and links.
-
- IEN 128 and 129 by Postel on IP and TCP.
-
- These are the second try at the DOD Standard versions of the IP
- and TCP specifications. These are also the current specifications
- for our own (ARPA internet) use.
-
-
-
- Postel [Page 7]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- In addition to these, four more IENs were received since the Thursday
- before the meeting:
-
- IEN 130 is a "Comparison of X.25 and TCP as Cable Bus Network
- Protocols" by International Computing.
-
- IEN 131 and IEN 132 by David Flood Page on "Gateway Monitoring
- Protocol" and "The CMCC Terminal Process."
-
- IEN 133 by Karen Sollins on "The TFTP Protocol."
-
- Two IENs which were desired but not produced were:
-
- "How to Build a Host IP" by Bill Plummer
-
- and
-
- "Congestion Control" by Dave Clark.
-
- V. FAX STATUS - Cerf
-
- Vint reported that Duane Adams of ARPA/IPTO is starting a program on
- graceful interaction and the test application will be multi-media
- computer mail. Since some of the internet project participants have
- FAX equipment there was a small meeting on how to cooperate to
- exchange FAX data. The internet program has interest in seeing that
- the exchange of multi-media data is possible in the internet and that
- the representation of such data is compatible between these programs.
-
- VI. INTERNET MAIL - Postel
-
- Jon presented the current status of the internet mail system. The
- system replaces the traditional "Mailer-FTPSRV" processes with new
- processes called MPM's. The MPM exchange messages which are list
- structured data of various types (not just text). The MPMs use TCP
- to transmit these messages. Some other programs have been modified
- or created to create test messages in this new format. No user
- interface to this new system exists yet.
-
- VII. BBN - FAX - MAIL - Myer
-
- Ted described BBN's work on a user interface program to manipulate
- messages composed of mixtures of text and FAX data. The focus is on
- the creation of such messages and on their presentation. The RAPICOM
- 450 will be used experimentally, and the files will be kept in a
- format very close to that used by Postel's MPMs.
-
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- Postel [Page 8]
-
-
- IEN 134
- Internet Meeting Notes
-
-
-
- VIII. GATEWAY MONITORING - Flood Page
-
- David reviewed the operation of the Catenet monitoring center and the
- terminal process, indicating the types of information available.
- Please see IENs 131 and 132 for more details.
-
- IX. DEMOS
-
- A. David Flood Page gave a demo of the CMCC by using a terminal
- process to examine the statistics sent in by various gateways.
-
- B. Greg Finn gave a demo of the Internet Mail system by running
- instrumented versions of the MPMs such that the progress of
- message processing could be followed.
-
- X. PUP - Shoch, Taft, Boggs, Stewart
-
- John presented a review of the PARC developed ETHERNET and PUP
- protocol environment. This was a very thorough presentation. Rather
- than try to capture it here the reader is referred to "PUP - An
- Internetwork Architecture", a paper to appear in the IEEE
- Transactions on Communication in April, and available as a Xerox
- report from John.
-
- John demonstrated some simple programs which use the PUP protocols
- and some monitoring programs. Ed demonstrated the Laural Mail
- Program, Dave demonstrated a cross network debugger, and Larry
- demonstrated the PRNET/ETHERNET interconnection and some digital
- audio transmission on the ETHERNET.
-
- XI. PUP-IP COEXISTENCE - Cohen
-
- Danny presented the scheme described in IEN 126 for the "mutual
- encapsulation" (credit Bob Metcalfe for the term) of PUP in IPs and
- IPs in PUPs.
-
- XII. DELTA-T PROTOCOL - Watson
-
- Dick made a presentation highlighting the critical assumptions about
- time in both the Delta-T protocol and TCP. The claim is that for
- either of these protocols to operate correctly these critical time
- factors must exceed specific minimum values based on the Maximum
- Packet Lifetime, the retransmission time, and the Ack holding time.
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- Postel [Page 9]
-
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- IEN 134
- Internet Meeting Notes
-
-
-
- XIII. LIMITING PACKET LIFETIMES - Sloan
-
- Lansing presented a scheme for measuring the time a packet spends on
- a link. This would enable a network to age packets and if necessary
- kill them off if they get older than an established maximum packet
- lifetime. This method will be reported in a paper to appear in
- Computer Networks.
-
- XIV. ST - Forgie
-
- Jim reviewed the discussion and evolution of ST since last meeting.
- IEN 119 remains a reasonable reference to the intention and general
- mechanisms of ST, though some details may now differ. A revised
- version is to be issued soon. Plans are moving ahead for
- implementations of a host and a gateway ST at LL and a host ST at
- ISI.
-
- XV. PORT EXPANDER - Lieb
-
- Jim presented a very detailed explanation of the Port Expander. This
- simple concept of multiplexing the IMP port for a set of host becomes
- fairly tricky when all the IMP emulation tasks are identified.
-
- XVI. SERVICES IN AN INTERNET ENVIRONMENT - Rom
-
- Raphi proposed that some gateways may wish to offer services to
- higher level protocols by having application-dependent modules that
- could be invoked to process messages of that application. These
- modules could be called "functional agents."
-
- XVII. NBS STANDARDIZATION - Wingfield
-
- Mike reported that BBN is under contract to NBS to prepare a
- host-to-host protocol specification to be a Federal Information
- Processing Standard. This is part of a larger effort by NBS which
- includes the following contractors and protocols:
-
- BBN - Host, FTP, IP, Interprocess.
-
- SDC - Telnet, Remote Job Entry, Common Command Language.
-
- SEI - Computer Mail.
-
- NAC - Cost/Benefit of Standards.
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- Postel [Page 10]
-
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- IEN 134
- Internet Meeting Notes
-
-
-
- XVIII. INTERNET PERFORMANCE - Davies
-
- Brian discussed some measurements of TCP conducted by RSRE to various
- other places in the internet. The performance is regular for round
- trips from RSRE to various points at UCL, and is consistent with the
- physical facilities. Once the round trip path includes the SATNET,
- however, the performance becomes irregular, with a few messages
- subject to very high delay. Also some unnecessary retransmissions
- are detected in the tests form RSRE to ISIE and back, these may be
- due to a too low retransmission threshold.
-
- This prompted some discussion of the source of the variability in the
- delay. Jim Forgie presented some data from the SATNET speech testing
- that seemed to confirm Brian's data. Dale McNeill showed some data
- on the SATNET channel delays which show performance at that level to
- be very regular. Suspicion seems to be cast on the SIMPs or the
- Gateways or their interface.
-
- XIX. CONGESTION CONTROL - Mills
-
- Dave described some measurements of TCP traffic between the COMSAT
- DEMO Terminal and ISIE. There is evidence of lost and delayed
- packets.
-
- It seems clear from this and the preceeding discussion that a
- definite effort is needed to isolate and correct these performance
- problems.
-
- XX. MISCELLANEOUS - Cerf
-
- Vint noted the following loose ends that need to be tied up:
-
- 1. 96 bit leader changes to all ARPANET hosts, and carried
- through system and application software.
-
- 2. TCP implementations brought up to the JAN 80 specifications.
-
- 3. IP implementations brought up to the JAN 80 specifications,
- and modified to including reassembly/fragmentation, gateway
- routing advice, alternate gateway selection, and source quenching.
-
- 4. Gateway addresses needed in all host IP tables.
-
- Vint also noted that work on a TCP TIP has been started. That an
- ARPANET/TELENET gateway is in progress, and that an ARPANET AUTODIN
- II gateway is expected in first quarter of 1981.
-
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- Postel [Page 11]
-
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- IEN 134
- Internet Meeting Notes
-
-
-
- XXI. NEXT MEETING - Cerf
-
- The next meeting is scheduled for 14 & 15 May at MIT. The contact is
- Dave Clark (Clark@MIT-Multics).
-
- XXII. DOCUMENTS DISTRIBUTED
-
- IEN Author Title
- --- ------ -----
- 127 Postel Assigned Numbers
- 128 Postel IP Spec
- 129 Postel TCP Spec
- 130 Comparison of TCP & X.25
- Watson Comparison of TCP & Delta-T
- Lieb Port Expander
- Mills COMSAT Reports
- Postel Internet Host and Gateways
- Postel IEN Index
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- Postel [Page 12]
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- IEN 134
- Internet Meeting Notes
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- XXIII. ATTENDEES
-
- Vint Cerf ARPA Cerf@ISIA
- Mike Brescia BBN Brescia@BBNE
- Jack Haverty BBN JHAVERTY@BBND
- Dale McNeill BBN DMCNEILL@BBNE
- David Flood Page BBN DFLOODPAGE@BBNE
- Ted Myer BBN Myer@BBNA
- Ruth Nelson BBN RNelson@BBND
- William Plummer BBN Plummer@BBNA
- Bob Resnick BBN Resnick@BBNA
- Virginia Strazisar BBN STRAZISAR@BBNA
- Mike Wingfield BBN Wingfield@BBND
- Hoi Y. Chong COMSAT Chong@ISIE
- David Mills COMSAT Mills@ISIE
- Chris Elliott CTEC c/o Chips@BBNC
- Ed Cain DCEC DCEC-R850@BBNB
- Ray McFarland DoD McFARLAND@ISIA
- Danny Cohen ISI Cohen@ISIB
- Greg Finn ISI Finn@ISIE
- Jon Postel ISI Postel@ISIE
- Carl Sunshine ISI Sunshine@ISIE
- Lansing Sloan LLL DWatson@BBNB
- Dick Watson LLL DWatson@BBNB
- Estil Hoversten Linkabit Hoversten@ISIA
- Jim Forgie Lincoln Lab FORGIE@BBN
- David Clark MIT Clark@MIT-Multics
- Anita Skelton MITRE Anita@MITRE
- Frank Deckelman NAVELEX DECKELMAN@ISIA
- Yngvar Lundh NDRE Yngvar@SRI-KA
- Paal Spilling NDRE/SRI Spilling@SRI-KL
- Merle Neer NOSC Neer@ISIA
- Brian Davies RSRE RSRE-T4@ISIA
- John Laws RSRE RSRE-T4@ISIA
- David Kaufman SDC Kaufman@ISIE
- Don Cone SRI Cone@SRI-KL
- William Croft SRI Croft@SRI-KL
- Elizabeth Feinler SRI Feinler@SRI-KL
- Mike Frankel SRI Frankel@SRI-KL
- Michael Heathman SRI Heathman@SRI-KL
- Ron Kunzelman SRI Kunzelman@SRI-KL
- Jim Mathis SRI Mathis@SRI-KL
- Stevan Milunovic SRI Milunovic@SRI-KL
- Holly Nelson SRI HNelson@SRI-KL
- Ed Perry SRI Perry@SRI-KL
- John Pickens SRI Pickens@SRI-KL
- Raphael Rom SRI Rom@SRI-KL
- Ron Jones UCL UKSAT@ISIE
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- Postel [Page 13]
-
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- IEN 134
- Internet Meeting Notes
-
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- Peter Kirstein UCL Kirstein@ISIA
- Steve Treadwell UCL UKSAT@ISIE
- Bob Braden UCLA OAC Braden@UCLA-CCN
- David Boggs Xerox Boggs@PARC
- Steve Butterfield Xerox Butterfield@PARC
- Dave Redell Xerox Redell@PARC
- John Shoch Xerox Shoch@PARC
- Larry Stewart Xerox LStewart@PARC
- Ed Taft Xerox Taft@PARC
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- Postel [Page 14]
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