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Here, my sipxbridge runs on 192.168.5.75 and accepts inbound signaling on port 5080 and symmetrically maps UDP traffic going both ways in the port range 30000:31000
It is possible in versions 4.4 and later to allow sipxbridge to listen for inbound SIP trunking on port 5060 while simultaneously listening for SIP Proxy requsts. This is done by enabling the bridge-proxy-relay setting in Server -> Services -> SIP Proxy.
Adtran firewall settings
ip rtp firewall-traversal
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