OpenWrt Forum Archive

Topic: network analyzer

The content of this topic has been archived on 3 May 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hello,
I'm searching for an ipk network analyzer (an Ethereal like), to evaluate some network parameters like packet delay, jitter and packet loss. I installed Iperf, which generates TCP and UDP traffic and is very useful for me, but this application doesn't tell me any information about packet delay parameter.
Do you know any already-packed WRT software?
Thank you

I think what you want is etherape and not ethereal (which is a packets sniffer).

Well, I didn't know etherape, but I know that using ethereal, is possible post-analyze sniffed packets to make the statistics I need.
It appears that is possible to make the same thing with tcpdump, which actually is included in OpenWrt backports. For linux platforms, there is a program called Argus (http://www.qosient.com/argus/) which permits to measure jitter, packet loss and packet delay of sniffed packets just reading tcpdump binary files.
Do you know anything about it? I'm googling hard, and I also wrote on tcpdump mailing list.
Thank you.

You can tcpdump to a file:

tcpdump -w /tmp/dump.trace -s 65000 -i eth0

I always use -s 65000 because otherwise tcpdump will only capture packets partitially. Last time I created packet statistics using ethereal, it was not using the actual size of the packets but instead the captured size. My statistics were flawed because of this. Hence the "-s 65000". I think it's an Ethereal bug. You might or might not need this.

After this you just open the trace file with Ethereal.

(Last edited by keitsi on 20 Mar 2007, 11:33)

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