Appendix: Router/Firewall Port Forwarding - Panasonic KX-HTS Series Setup Reference Manual

(8) Appendix
UDP hole punching for keeping in Router/Firewall Port Forwarding
If VozTelecom's Keep Alive message (OPTIONS UDP packets) is not effect to keep port forwarding
for external router, configure the OPTIONS packet to enable as keep-alive message on the PBX SIP
Trunk Property.
If necessary,
For External router setup, configure Port Forwarding on the router as follows:
udp port 5060 – to HTS WAN1 IP address (e.g. 192.168.22.99)
udp port range 12000-20000 (RTP) – to WAN1 IP address (e.g. 192.168.22.99)
IMPORTANT!
To secure the PBX from illegal attacks, please restrict the above port forwarding ports to only
be accessible from the VozTelecom source IP addresses.
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