Wireshark-users: Re: [Wireshark-users] end-to-end delay calculation

From: "Rob MacKenzie" <rmackenzie@xxxxxxx>
Date: Thu, 13 Mar 2008 12:16:46 -0400

I looked at re-writing ping once to test time difference…  IF your endpoints are in the same building, consider running a wire between the parallel ports and code something to check the exact time when you flip a switch or something.  Then you would have a trigger time for both.

 


From: wireshark-users-bounces@xxxxxxxxxxxxx [mailto:wireshark-users-bounces@xxxxxxxxxxxxx] On Behalf Of Martin Mathieson
Sent: March 13, 2008 12:13 PM
To: Community support list for Wireshark
Subject: Re: [Wireshark-users] end-to-end delay calculation

 

If you have console / command prompt of some type, most operating systems have a ping command that uses ICMP to test connectivity and routrip delay to a remote host and back.
But I don't know what OS or environment is running on your endpoints.

On Thu, Mar 13, 2008 at 4:05 PM, Fabiana moreno <fvmoreno@xxxxxxxxx> wrote:

how can do the ping? I dont know what this is

 

On 13/03/2008, Martin Mathieson <martin.r.mathieson@xxxxxxxxxxxxxx> wrote:

You could of course do a ping.  And see how close to the middle the far side sees something happen...

 

On Thu, Mar 13, 2008 at 2:49 PM, Fabiana moreno <fvmoreno@xxxxxxxxx> wrote:

Well i did this...but i dont know if it's ideal...i think it would work though....

I synchronized the two computers to a server on the internet before every capture so both have the exact same time.

i have my sniffer in the two computers, the one that sends and the ones that receive.

I created a function in matlab that calculates the difference between those two times...

I am being really carefull when i have a packet lost or things like that....

But probably this can work???? ...

 

On 13/03/2008, juan.wortley@xxxxxxx <juan.wortley@xxxxxxx> wrote:

Hi Fabiana,

 

the only way to do that is if you know the time difference between the machines.

It´s not so easy however if you use windows you could try synchronizing both endpoints by using:

w32tm /config /manualpeerlist:[IP to synchronize to] /update /syncfromflags:MANUAL

 

and then monitor the time difference with:

w32tm /stripchart /computer:[IP to synchronize to]

 

,you always can have a delay reference by pinging and dividing by 2 the RTT.

 

HTH

Juan

 

 


From: wireshark-users-bounces@xxxxxxxxxxxxx [mailto:wireshark-users-bounces@xxxxxxxxxxxxx] On Behalf Of ext Fabiana moreno
Sent: Miércoles, 12 de Marzo de 2008 09:38 a.m.
To: Community support list for Wireshark
Subject: Re: [Wireshark-users] end-to-end delay calculation

so ... it is not reliable if i substract the time i hav in the client minus the time i have in the server to get my end the end delay? 

On 12/03/2008, Hansang Bae <hbae@xxxxxxxxxx> wrote:

Fabiana moreno wrote:
> Hello there,
>
> I know wireshark is not able to calculate the end-to-end delay of a
> packet when streaming. I was just wondering if adjusting the clocks of
> my two computers(sender and receiver) to the network time protocol and
> having the sniffer at both ends i could calculate the end-to-end-delay
> tracing each packet. Does this sound logical?
>


It is within the limits of ntp.  Unless there is a WAN involved, the
packets are flying around at an order of magnitude faster than what ntp
can provide (ms resolution)

--

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

 


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

 


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

 


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

 


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

 

---------------------------------------------------------------------
This transmission (including any attachments) may contain confidential information, privileged material (including material protected by the solicitor-client or other applicable privileges), or constitute non-public information. Any use of this information by anyone other than the intended recipient is prohibited. If you have received this transmission in error, please immediately reply to the sender and delete this information from your system. Use, dissemination, distribution, or reproduction of this transmission by unintended recipients is not authorized and may be unlawful.