vpn, voip and port related question

tusher · 11-14-2006, 07:19 PM

Hi All,

My ISP has blocked -or- start tracing perticular packet type (Voip), so, I can't use
sip/h323 voip service any longer. I need to check which port are blocked by my ISP.

so, I have 2 questions.

1. what is the way , I can check which port still remain open by my ISP
2. Is there any perticular port used by VPN technology? Is this possible to
restrict use of VPN (blocking vpn port) by ISP ?

This is very urgent.

Thanks,

Mara · 11-15-2006, 01:10 PM

1. Probably all over 1024, with very small number of exceptions, are open. To check that you'd need an machine outside with global IP that will allow you to try connections to all ports.
2. Port 1723 is quite popular. Most programs allow you to use any port you wish.
3. Check your ISP service agreement (the one you have signed). It may be just one phone call to unblock the services you need.