Trevor Tolk wrote:
I'm going to be testing the QoS of our WAN network.
I've done some user level testing, now I want to do some more in-depth
testing. My plan is to saturate the network with non-QoS'd traffic,
start running some QoS'd traffic over the wire, then monitor on both
ends to verify that QoS'd traffic doesn't get dropped.
I've not done a comparison of point A vs. point B before. Does anyone
have any advice?
There are two ways you can do this.
Method one. Capture on the sending and receiving computers while the
link is saturated. It then becomes trivial to compare the sending and
receiving side's packet traces. This will allow you to use UDP based
testing to ensure QoS is working.
Method two: If you use tcp based testing program, or if your QoS
protected traffic is TCP based, you can try the app with and without QoS
protection. Since it's tcp based, you'll start to see retransmissions
as packet loss occurs. If your QoS is working properly, you should not
see any packet loss even when the link is saturated. You can quickly
check for tcp events by using the "tcp.analysis.flags" filter.
Hopefully, you should see a lot of retransmissions when QoS is turned
off and none (or near zero) retransmissions with QoS turned on.
Have fun!
