Understanding SIP ALG and Its Impact on VoIP Calls
SIP ALG (Session Initiation Protocol Application Layer Gateway), also referred to as SIP helper or SIP stack, is a router feature designed to manage VoIP traffic by modifying SIP packets, particularly IP addresses and port numbers. While its intention is to facilitate smoother call handling, SIP ALG often causes more harm than good due to poor implementation in many routers.
When enabled, SIP ALG can disrupt VoIP services, leading to issues like one-way audio, dropped calls, call transfer failures, and malfunctioning call groups. In many cases, disabling SIP ALG is the most effective way to resolve these problems and ensure reliable communication.
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How to disable SIP ALG?
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Example: What can go wrong with SIP ALG
FAQ
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Related Pages
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