Introduction
SIP ALG is used to try and avoid configuring Static NAT on a router. Its implementation, however, varies from one router to another, often making it difficult to inter-operate a router with SIP ALG enabled with a PBX. In general, you would want to disable SIP ALG and configure one to one port mapping on the router.
In this article, we will show you how to disable SIP ALG on a Netgear router. SIP ALG on this router is known to cause problems with VoIP calls.
Follow this step-by-step guide:
Option 1
- Open the Netgear router configuration by browsing to its LAN Address (http://192.168.0.1 by default).
- Log in to the router’s configuration. The default username is “admin” and the default password is “password”.
- In the main menu, select “Advanced” → “WAN Setup”.
- Enable the option “Disable SIP ALG”.
- Click “Apply”.
Option 2
- Open the Netgear router configuration by browsing to its LAN Address (http://192.168.0.1 by default).
- Log in to the router’s configuration. The default username is “admin” and the default password is “password”.
- In the main menu, select “Security” → “Firewall” → “Advanced”.
- Uncheck the option “Enable SIP ALG”.
- Click “Apply”.
Notes
- The SIP phones behind this router should be configured not to use STUN.
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