Technical Information

One of the most common problems that we encounter in setting up a customer’s service is the firewall, particularly for enterprise customers where the IT manager has set up the firewall to restrict ports or only open up specific IPs. 

Prodosec Inc is it's own ISP with it's own IP blocks, advertising as BGP network AS53441

All traffic to/from Prodosec will originate or terminate in the following IP ranges.


  • Network IP
  • Network IP


At a minimum allow traffic to and from the following port numbers. Open up ports:

5060 TCP and UDP - For SIP signaling traffic.

10000 – 65535, UDP - For RTP audio packets.


Firewall problems are characterised by:

  • No calls going through (IP or ports blocked)
  • Outgoing calls working, but not incoming (ports blocked or NAT related)
  • One way audio (ports blocked or NAT related)
  • Calls cutting after a short duration (ports blocked)


If your network administrator is unwilling to open up your entire network to these ports, you may want to consider these settings just for your VoIP server or moving your VoIP server to a static IP in a DMZ.


IF you are having trouble with static IP's and firewalls, we suggest using a "registration SIP account" instead. These are better at traversing firewalls and avoiding the issues.