[Cu-wireless] two TCP analysis programs

[David Young]

Here are two tools for analyzing TCP traces. They might make it easier
to study HTTP/SSH sessions that falter.

tcptrace and tcpillust are programs that produce diagrams from TCP
captures made by tcpdump. The diagrams made by tcpillust are ladder
diagrams in the style of TCP Illustrated. Tcptrace seems to produce a
few kinds of diagrams---read the manual (it's at tcptrace.org).

You can produce TCP packet traces on C-U Wireless hosts using tcpdump:

tcpdump -np -w /tmp/dumpfile -i wi0

Option -n suppresses name lookups, -p keeps tcpdump from switching the
interface to promiscuous mode (very important!), -i selects the interface,
-w names the output file.

tcpillust seems to like two (or more?) traces best.  It might be important
for the clocks on all the hosts to be synchronized. =)

Dave

-- 
David Young             OJC Technologies
dyoung at ojctech.com      Urbana, IL * (217) 278-3933