Subject: Re: Throughput measurement in Ad-Hoc Networks

From: "Abhishek Kumar" <[email-masked]>
Date: Thu, 1 Feb 2001 08:21:40 -0600

HI

>We are trying to measure the throughput of an ad-hoc Network that we
> have
>simulated using ns (2.1b7a). Does anyone know how to do this? We tried
> to
>use per-flow monitors but it seems it doesn't work in ad-hoc networks
>because it needs a (wired) link between the nodes.

If your flows are TCP, you can get the total number of packets acknowledged on a flow at any point in time. This can be done by acessing the configuration parameter ack_ of your TCP objects.
The NS documentation (chapter 10.8) defines it as :

ack_ 
Highest acknowledgment seen from receiver.

This can be used to get both the cumulative and instantanious "throughput" for individual TCP flows. Note that you can get only the number of acknowledged packets and thus the lost packets are not counted. Thus what you are really measuring is not raw throughput of the network, but the "goodput" of TCP flows.

Hope it is useful.

Cheers
abhishek

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Abhishek Kumar
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