T38Fax owns 8.34.182.0/24 (AS7324), and all of our services operate out of the 8.34.182.0/24 address block. Ports 5060 and 5080 are for SIP. Use of the non-standard port 5080 is recommended, and discussed in more detail here. The other ports mentioned are for RTP or UDPTL, the media streams. The SIP packets and RTP packets for a single session will often use different IP addresses.

8.34.182.111         UDP 5060, 5080, 35000-65000

8.34.182.112         UDP 5060, 5080, 35000-65000

8.34.182.113         UDP 5060, 5080, 35000-65000

8.34.182.100/30    UDP 16384-65000

8.34.182.128/26    UDP 16384-65000