Noisemarine. My mistake, the inbound\outbound calls to\from the remote ITP are connecting but with no 2-way audio about 50% of the time. My main location with the 7030 is on a 192.168.75.x network and the remote ITP is on a 192.168.76.x network. Routing is working between the subnets over a generic Cisco GRE VPN. I've added the remote subnet to MMC838. At the main location I have a ACL on the Cisco881 to allow the full IP (all ports) to passthru from ITSP so this should cover all the Ports needed for VoIP.

I'm not clear if after the Call Setup (SIP) on an inbound or outbound call to\from the ITP that (RTP) passes from the ITP to the 7030 over the VPN and then to ITSP or if the ITP passes (RTP) traffic directly out the local router to the Internet(not over VPN).

Both locations access the Internet directly, only site-to-site traffic is routed over the VPN. I'm not seeing any VoIP\NAT traffic on the remote router so I assume all ITP traffic goes directly to the 7030 over the VPN and then to ITSP. If I had router\firewall issues wouldn't the problem consistently not work? the 50\50 random occurrences is what is throwing me for a loop.

The Cisco881 has a embedded packet capture feature. So, I've setup an ACL to capture traffic based on ITSP public IP. I can then TFTP this capture buffer to my PC for Wireshark\SIP analysis. I'm going to try an capture a trace for successful and fail call to see if I can determine anything different on the traces.

I would like to test or rule out anything simple before I start trying to analyze traffic.

Old Network Guy and New Phone Guy, CLI=MMC?