Cisco 800 VPN behind firewall

Unanswered Question
dhananjoy chowdhury Wed, 07/16/2008 - 09:56

Hi It depends on what type of VPN you have...

For IPSEC vpn's you need = UDP 500 (also sometimes it may need UDP 4500 and 10000)

for PPTP vpn = TCP 1723

Hope this helps.

michael.leblanc Thu, 07/17/2008 - 06:55

If you are not using UDP or TCP encapsulation of IPSec to get through a NAT process, then you would also need to include the IPSec encapsulation protocol(s) being used:

Encapsulating Security Payload is IP protocol 50.

Authentication Header is IP protocol 51.

... in addition to the port numbers specified by the other responder.


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