I'm trying to connect to my workplace using a VPN connection, however I'm behind a firewall and I need to know what ports the connection will use to ask the network adiministrator to open them. I'm using Windows Vista and the VPN Server runs on a Windows 2003 Server machine.

+3  A: 

What sort of vpn are we talking about?

There are a few types. If you're doing L2TP, you'll need UDP port 500 and ESP (it is its own protocol) allowed.

PPTP is pretty similar, uses GRE instead of ESP and TCP port 1723

Please note though that I don't think ESP or GRE have port numbers, which makes it hard to perform NAT sometimes. But aslong as noone else behind your router is trying to connect to the same place it should be ok

+3  A: 

If you are using PPTP for VPN, then the port is TCP port 1723. See the Wikipedia PPTP page.


Many routers have a "VPN Pass-thru" feature.

Darcy Casselman

If you're using a VPN that takes advantage of GRE, you'll have to turn on stateful packet inspection on your router, which will be able to conntrack outside of TCP/UDP. GRE is a protocol that directly rides IP. (It's layer 4+). Contact your NAT manufacturer for more information .

Sargun Dhillon

I recommend you to visit vpn about more info