Path: utzoo!utgpu!watserv1!watmath!att!ucbvax!proteon.com!rvs
From: rvs@proteon.com (Ray V. Samora)
Newsgroups: comp.sys.proteon
Subject: using p4200 as x.25 DDN gateway
Message-ID: <9009111357.AA25817@sonny.proteon.com>
Date: 11 Sep 90 13:57:25 GMT
References: <9009101504.AA07156@devvax.TN.CORNELL.EDU>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 31

David,

After looking at your configuration, I can offer a few tips to help
improve throughput.

You should increase the frame layer window size from 5 to 7, 7 is the
default setting for mod8 and will help increase the number of frame
layer frames in transit prior to needing end-to-end acknowledgement.
Also, I noticed the packet window size is set to 5, some nets
(Telenet) require a setting of 2.  If 5 is ok with the psn, try for 7,
this will also help throughput.

The default packet size setting at 256 is ok, however the larger the
better, say 512.  Larger settings cut down on the need for
segmentation and reassembly which are costly.  The maximum packet size
setting is also too high is the negotiated packet size steps down to
256, this leads to a lot of buffer waste that can't be used.

You have flow control negotiation turned on, this is good if the
remote DTEs support this, otherwise hand tailored configuration that
is acceptable for both ends is called for.  Also, the default window
should be set <= packet window size for optimal negotiation.

The max calls out setting (default at 4) can be increased which will
yield more circuits in the event things are backing up.  In addition,
what is the interface data rate (modem) set at, try to get that
increased if you can.  Also, the circuit idle time is set to 15
seconds, circuits with bursty traffic will benifit with a higher value
to avoid the need to restablish circuits to the same destinations.