Wireshark · Wireshark-users: Re: [Wireshark-users] How to get Average RTT

[Ed.Staszko@xxxxxxxxxxxxxxxxx]

You can get a graphing of maximum, average and minimum RTT, if you use the
IO Graph function with Ethereal (the timings are inaccurate in Wireshark).
You need to use the "Y: Axis/Unit/Advanced" selection and select the AVG(*)
option in the "Calc:" column.
Fill in with this Calc value:

 tcp.analysis.ack_rtt

This will display the average RTT for all TCP sessions in the trace.

This is extremely valuable for calculating the RTT for a particular site,
as you can additionally add a filter in the "Filter:" column for a remote
subnet.
You can also compare the RTT's for different components of your QOS by
setting up 2 graphs, with each being filtered on an appropriate value for
each group in your QOS.
We use it for comparing Citrix RTT's vs. print traffic RTT's, and expect to
see a fairly consistent value for Citrix (high priority) and possibly
radical differences in print (low priority). If the high priority traffic
starts having large swings in RTT values, you are probably undervalued in
the QOS queue settings for this high-priority traffic or the link is
overloaded by high-priority traffic.

It is important to note that, at this time, the Wireshark computations for
the IO Graph RTT's are NOT accurate. You must go back and use Ethereal (I
am using 0.10.14)

Ed Staszko
Network Analyst
Mutual of Omaha



                                                                           
             "Marc Glenn"                                                  
             <mjamon@xxxxxxxx.                                             
             co.jp>                                                     To 
             Sent by:                  "Community support list for         
             wireshark-users-b         Wireshark"                          
             ounces@wireshark.         <wireshark-users@xxxxxxxxxxxxx>     
             org                                                        cc 
                                                                           
                                                                   Subject 
             07/18/2007 12:12          Re: [Wireshark-users] How to get    
             AM                        Average RTT                         
                                                                           
                                                                           
             Please respond to                                             
                "Community                                                 
             support list for                                              
                Wireshark"                                                 
             <wireshark-users@                                             
              wireshark.org>                                               
                                                                           
                                                                           




Stephen Fisher wrote:
      On Wed, Jul 18, 2007 at 11:46:20AM +0800, Marc Glenn wrote:


                I tried viewing the Round Trip Time Graph ins
            Statistics->TCP
            Stream Graph->Round Trip Time Graph but I was not able to get
            an exact
            value for the average Round Trip Time.


      So the graph showing you the data you want, just without the actual
      measurements shown that you need?


      Steve

      _______________________________________________
      Wireshark-users mailing list
      Wireshark-users@xxxxxxxxxxxxx
      http://www.wireshark.org/mailman/listinfo/wireshark-users


Yeah. I think the graph can help if only it computes the average RTT for
the whole set of packets.

Marc Glenn
_______________________________________________
Wireshark-users mailing list
Wireshark-users@xxxxxxxxxxxxx
http://www.wireshark.org/mailman/listinfo/wireshark-users



This e-mail and any files transmitted with it are confidential and are solely for the use of the addressee.  It may contain material that is legally privileged, proprietary or subject to copyright belonging to Mutual of Omaha Insurance Company and its affiliates, and it may be subject to protection under federal or state law.  If you are not the intended recipient, you are notified that any use of this material is strictly prohibited.  If you received this transmission in error, please contact the sender immediately by replying to this e-mail and delete the material from your system.  Mutual of Omaha Insurance Company may archive e-mails, which may be accessed by authorized persons and may be produced to other parties, including public authorities, in compliance with applicable laws.