Buffer tuning has long been an interesting topic for me. I recently found a blog post by Brough Turner, who wrote an interesting article about a potential misconfiguration of AT&T wireless routers that cause ping round trip times to be either < 200ms or around 8000ms (yes, 8 seconds!). http:/...

I'm working on a QoS job and we're not trusting the phones. I presume that most everyone has heard of the hacking that some fellows did to break into a hotel's network by using a small program that made their PC look like a Cisco phone. The switch then trusted the phone-a-like-PC and they...

I'll periodically run into someone who is attempting to implement policy routing by modifying interface bandwidth statements. What they're trying to do is to have traffic prefer a certain path through their network by either increasing or decreasing the bandwidth of a link, therefore forcing...

VoIP troubleshooting is a pretty interesting problem. (See my earlier blog entry regarding my talk at VoiceCon Fall 2007.) There are a large number of tools that look at packets on the wire, or look at the RTCP (Real Time Control Protocol) stream from certain phones, or gather data from the call controllers...