Hi guys I know this is a linksys rather than CISCO forum but uve been helpful in the past so hopefully I can get this. Ok trying to figure someone elses problem out and tryin to help. -Site to Site VPN . Works fine from one ISP to another and visa versa, but when the 2 are on same ISP it doesnt connect. e.g Site A and B are both on same ISP Site A has cisco PIX firewall able to terminate VPN connection , Site A can be VPNed to and from when dealing with an outside ISP. But connecting to Site B with (which is same ISP) wont connect. Site B same PIX setup,the same cant connect to A on same ISP but if I try to connect to 3rd site on different ISP it works. ISP DOES NOT BLOCK ANY PORTS, I can ping site A and Site B from the other side so there isnt a routing issue. As a matter of troubleshooting I have gotten ping allowed on both sides as a way of testing connectivity between 2 sites and it pings fine.