Thanks Martin, I have never done any graphing at all and didn’t know about the ack_rtt.
In this case, It seems that the ack_rtt shows the rtt between the SYN and the next packet, I need to know if there were any packets in the conversation (from SYN to FIN) that have a high RTT…..is there a way to do that?
johnny
From: wireshark-users-bounces@xxxxxxxxxxxxx [mailto:wireshark-users-bounces@xxxxxxxxxxxxx] On Behalf Of Martin Visser
Sent: Wednesday, January 04, 2012 5:45 PM
To: Community support list for Wireshark
Subject: Re: [Wireshark-users] Question about seeing Latency in TCP conversations
Johnny,
The easiest way is to examine the calculated field "tcp.analysis.ack_rtt". This appears in the details window if you have TCP Sequence Analysis on.
You have to be a little careful when using this though, as Wireshark sometimes miscalculates this in the prescence of Duplicate ACKs. The best way to use it (taking out effects of the server processing delay), is during the initial handshake. So what I do is filter for "tcp.flags == 0x12" (which is the SYN/ACK) and plot tcp.analysis.ack_rtt or add it as a column.