Configuring Nat Mapping With Stun - Linksys RTP300 - Broadband Router With 2 Phone Ports Administration Manual

Configuring Your System for ITSP Interoperability
6. Click Submit All Changes.
NOTE: You also need to configure the firewall settings on your router to allow SIP traffic. See
"Firewalls and SIP, " on page

Configuring NAT Mapping with STUN

If the ITSP network does not provide a Session Border Controller functionality, and if other
requirements are met, it is possible to use STUN as a mechanism to discover the NAT mapping.
This option is considered a practice of last resort and should be used only if the other methods
are unavailable.
Requirements:
• STUN is a viable option only if your router uses asymmetric NAT. See
Whether the Router Uses Symmetric or Asymmetric NAT, " on page
• You must have a computer running STUN server software.
• The LAN switch must be configured to enable Spanning Tree Protocol and Port Fast on
the ports to which the SPA devices are connected.
NOTE: Use NAT mapping only if the ITSP network does not provide a Session Border
Controller functionality.
1. Connect to the administration web server, and choose Admin access with Advanced
settings.
2. Click Voice tab > SIP.
3. Scroll down to the NAT Support Parameters section, and then enter the following settings to
enable and support the STUN server settings:
• Handle VIA received: yes
• Handle VIA rport: yes
• Insert VIA received: yes
• Insert VIA rport: yes
• Substitute VIA Addr: yes
• Send Resp To Src Port: yes
• STUN Enable: Choose yes.
• STUN Server: Enter the IP address for your STUN server.
Linksys ATA Administration Guide
Network Address Translation (NAT) and Voice over IP (VoIP)
42.
"Determining
41.
40