[Freeswitch-users] How to set "keep-alives re-use the TCP connection" ?

Using Bria on iPad with a TCP connection, all works except after several hours it no longer registers to FreeSwitch. The Bria support says if this happens set the server PBX to use "keep-alives re-use the TCP connection". I could not find this options in the wiki, only thing close dealt with NAT but FS and the phones are all on local lan. Anyone know how to set this in the user definition? Thanks, Mario G