The main circuit at the remote office is a 12Mb provisioned DS3 link through the layer 3 switch. When this circuit goes down,the vpn tunnels on the router will route all traffic through the tunnel except tftp traffic to register the phones. Pings and trace routes are successful in both directions and are symmetrical between client and UCM. The UCM never receives the tftp request from a phone. Phone goes into SRST fallback as a result. Is this routing or a possible bug in UCM? Running 5.1.3-7109-1. Router running 12.4.(9)T7 on a 2651XM. Been working this issue for a year with no results. Thanks.