Hi - We've two outbound routes from a FreeSWITCH box, both done purely on IP - no SIP registration or authentication involved apart from by IP. We can route calls to one or the other by adding a Route header to outbound call setups, which works fine. What I can't obviously see how to do is to failover if one of the gateways disappears. Two options that I've come up with: - add some code to fail a call if a 100 Trying isn't received within a short time after sending the initial INVITE, so that it can be routed to the other gateway; - using an external app to periodically send OPTIONS to each gateway, work out which are alive, and route calls appropriately. Have I missed something obvious and straightforward? --Dave -- David Knell, Director, 3C Limited T: 020 8114 8901 F: 020 3002 7257 M: 001 415 630 3031 http://www.3c.co.uk