How can I determine the cause of dropped Vonage calls?

Archived from groups: comp.dcom.voice-over-ip (More info?)

Recently, I've been experiencing dropped calls and I would like to
pinpoint the cause so that I can correct the problem.

My calls are either dropped or become half-duplex (can only hear one
party). My broadband provider is Comcast and I've been using the
service for a year. Recently, the main cable was replaced and the
service worked fine immediately after that.

I'm running a ping monitor to determine if there's a network related
problem but I don't think that the ping will necessarily tell me much
because I don't (yet) know the IP address that my Vonage router is
talking to. A ping message is also small in comparison to the voice
traffic - so it is probably a poor measure of sustained throughput.

My configuration is a Motorola Surfboard SB5100? modem connected to a
Linksys RT31P2 router. My home network is downstream from the RT31P2
router and there is usually minimal traffic there.

Other things I have checked:

The cable modem has good signal strength.
Data traffic seems ok - web browsing, etc.
Ping monitor doesn't show anything obvious when pinging google.com

I may use ethereal to determine the IP address that the router is
talking to and run my ping test to there.

Any help or suggestions are welcome.

Chris
cjtwantstoknow