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July 18, 2004


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Shop Right

Can't speak to any actual blocking, but Vonage does not seem to work very well with Adelphia Cable - even at the lowest quality sound setting through Vonage, the 3-way calling feature never works - it results in choppy calls with everyone complaining they can't hear well enough to conduct the call. Online Internet speed tests oddly indicate that my Adelphia Cable is, if anything, above average speed. A friend suggested they may be limiting bandwith after a certain period of time (so that the speed test would appear to be fine, but prolonged use of significant bandwith would result in a clampdown of sorts from them, possibly affecting my Vonage) - anyone know if this makes any sense?

Jon Hunt

I can attest to the Adelphia block of UDP port 69. They are doing this to protect me from viruses... but what they are really doing is losing me as a customer... hello DSL!


I was recently invited to a 6mo free Callvantage VIP trial. After using the service for 2 weeks on Adelphia. The TA went dead (voice). AT&T informed me that Adelphia was blocking a port they needed (69) and that the issue would not be resolved until September, likely their timeframe for moving to SIP.


This doesn't make any sense - 69 is TFTP, which might be blocked to prevent configs from being sent to routers. Wouldn't they block SIP ports instead?

Charlie Sierra

I think a fast food TV commerical put it correctly when they said, "Ports, is Ports!"

Blocked ports are easily programmed around, thus blocking will never really work.

Abit off topic, but something I use is a technique known as "PORT-KNOCKING". If you want a very secure setup for remote access to your boxes, you can enable PORTKNOCKING, which will only open a port, after a predefined sequence of port access has transpired. Sort of a meta-password.

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