Ethereal-dev: Re: [Ethereal-dev] TCP Seq graph and users' guide.

Note: This archive is from the project's previous web site, ethereal.com. This list is no longer active.

Date Index Thread Index Other Months All Mailing Lists
Date Prev Date Next Thread Prev Thread Next
From: "Ronnie Sahlberg" <ronnie_sahlberg@xxxxxxxxxxxxxx>
Date: Tue, 19 Nov 2002 22:04:15 +1100
----- Original Message -----
From: "Pavel Mores"

> I'm not sure if there's much more information to be extracted from this
> simple type of graph.  This type of graph should be used for cursory
> examination only where the much more informative tcptrace-style graph
> can be confusing (exactly by the sheer amount of info it contains).  I
> included this graph style because it's simple and it's used by Stevens
> in his TCP/IP Illustrated masterworks for examining time/sequence number
> dependencies.  For a more serious analysis tcptrace-style graph should
> be used.
>

Oh but it produces incredibly useful output to spot tcp layer problems for
bulk transfer performance.

Horizontal gaps in the graph will tell you exactly where you have
retransmission timeouts and how long
the timeouts are.
This graph type can by eyeballing it for a few seconds tell you whether the
performance
problem lies in the TCP layer or not.

The only problem with it is that it only works ontop of Ethernet.
Porting it to grab data from a tap instead should fix that problem though.