Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.3 alpha 4/15/85; site ucbvax.ARPA Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!ihnp4!ucbvax!tcp-ip From: tcp-ip@ucbvax.ARPA Newsgroups: fa.tcp-ip Subject: MILNET/ARPANET performance Message-ID: <7548@ucbvax.ARPA> Date: Tue, 28-May-85 20:50:08 EDT Article-I.D.: ucbvax.7548 Posted: Tue May 28 20:50:08 1985 Date-Received: Thu, 30-May-85 03:15:16 EDT Sender: daemon@ucbvax.ARPA Organization: University of California at Berkeley Lines: 34 From: Mark Crispin Folks - I have spent a good bit of time feeling out Telnet performance to TOPS-20 sites on MILNET, ARPANET, and Canada's DRENET. I have observed that this performance between Milnet and ARPANET is, in a word, terrible. There are frequent echo delays of over a minute in duration. By comparison, ARPANET to DRENET performance is considerably more tolerable. In a number of instances, Telnet performance from an unloaded TOPS-20 system on ARPANET to another unloaded TOPS-20 system on Milnet has been terrible enough to make serious work nearly impossible, while access to the Milnet TOPS-20 from the Milnet TAC was smooth and quite usable. At times, the delays have been long enough for the Telnet user program to declare the connection dead. This is a guess, but I believe that the gateways are throwing out a lot of packets. Unless they've changed it, all three networks still endeavor reliable delivery of all 1822 messages so TCP reliable delivery is in theory not resorted to. It is probably traffic-related, since TCP performance between ARPANET and DRENET is tolerable in spite of the slow lines at DRENET. Telnet is a worse case test of this, due to its character at a time nature. I wonder if the TCP retransmission parameters need tuning depending upon whether the connection is on a reliable network (e.g. 1822) or is going through a gateway. -- Mark -- -------