VPN connection issue between 3005 concentrator based in California to India

[buddhika1]

We are having some difficulties w/ our VPN connection from India (using the Cisco VPN client) to California connecting to our 3005 VPN Concentrator. The VPN connects but nothing is pingable by name or ip. The average latency between the two sites is about 500ms which I assume is the issue, but I have never dealt w/ a VPN connection over such distances and dont know what the exact thresholds are for it. The India side has said they have connected over to the States using the Cisco client before, but at 500 ms latency I dont know how. If anyone can point me in the right direction I would appreciate it.

Thanks

[aacole]

Latency isnt causing your main problem here, I've just pinged a remote site with a similar latency:

Sending 5, 100-byte ICMP Echos to 172.16.65.1, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 492/497/504 ms

There are a couple of common problems I could think of that may be causing this failure. The first is that your crossing a NAT boundary somewhere, in which case the VPN does authenticate as it uses ISAKMP over UDP 500, but the IPSec encapsulated data fails due to a NAT altering the packets. Enabling NAT-T support fixes this.

The other is down to routing, one end not knowing how to route to the remote via the VPN link.