Network Working Group V. Cerf
Request for Comments: 21
October 17, 1969
At UCLA on October 10, there was a network meeting attended by:
John Kreznar Vint Cerf
Dick Linde Steve Crocker
Marty Bleier Jon Postel
Bob Long Michel Elie
1. Revisions to BBN memo 1822
2. Revisions to NWG/RFC 11
3. Transmission of multiple control messages1.
Changes to BBN Memo No. 1822 (underlined)
As informally communicated by Dave Wa
p. 11 "The IMP program can handle up to 63 active transmit links
and 63 active receive links at a time. If the Host attempts to
send a message on a new link when 63 active transmit links already
exist, a "Link Table Full" message will be sent from the IMP to
the Host, and the message will be discarded."
p. 11 "1. Any link that is not used for a period of 26 seconds
will have its entry automatically deleted by the IMP program."
[Cerf: How about deleting only if the transmit link table is full?
Crocker: No, because there is no other way for links to be deleted
so they would always tend to accumulate. Furthermore,
the table at one site may be full while another site may
p. 13 "5 Regular with discard."
This allows IMP systems to generate traffic which never actually
reaches any Hosts since it will be discarded when it reaches the
top of the IMP-HOST queue in the destination Host's IMP. The
Network Measurement Center will make use of this feature.
p. 13 Message type 6 is no longer assigned, and message type 10
is really in octal so is actually type 8. Types 9-15 are unassigned.
p. 17 Type 10 is really type 8.2.
Revisions to NWG/RFC 11
This memo has been obsoleted by developments at UCLA and
discussions with other nodes. NWG/RFC 22
contains some of the
major changes. An updated version of NWG/RFC 11
George Gregg of UCSB will publish NWG/RFC 23
transmission of multiple control messages over control links.