What is SIP ALG?
Ideally, most of the commercial routers consist of SIP ALG. It stands for Session Initiation Protocol Application Layer Gateway. Its function is to prevent the issues caused due to router firewalls. It does so by inspecting VoIP traffic and if found essential by modifying it.
How can it affect VoIP?
Although SIP ALG is expected to help clients who have telephones on private IP addresses, much of the time it is actualized ineffectively and causes a larger number of issues than it solves. Gradwell and different suppliers frequently find that the SIP ALG adjusts SIP parcels in unexpected ways, ruining them and making them indiscernible. This can give you unforeseen conduct, for example, telephones not enrolling and approaching calls fizzling.
Therefore if you are experiencing problems we recommend that you check your router settings and turn SIP ALG off if it is enabled.
This article addresses how to disable SIP ALG on your NETGEAR device using the Genie interface. SIP ALG (Session Initiation Protocol Application Layer Gateway) is common in many commercial routers. It prevents some of the problems caused by the router firewall by inspecting VoIP traffic (packets) and if necessary modifying them. By default NETGEAR routers have SIP ALG turned ON.
To disable SIP ALG on your NETGEAR device using the genie interface:
1. Connect to the NETGEAR device using a wired/wireless connection.
2. Once connected access the GUI interface of the NETGEAR device by typing http://www.routerlogin.net / 192.168.1.1 / 192.168.1.3 in the browser.
3. The router login screen will ask for a login and password. If you have not changed the password then the default username is admin and the password is the password.
4. Once logged into the NETGEAR genie page, click ADVANCED.
5. Click Setup.
6. Click WAN Setup.
7. On the WAN Setup page, disable SIP ALG by selecting Disable SIP ALG.