User manual

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SIP_ALG
Select Enabl to activate SIP ALG feature or Disabled to disable this feature.
The Session Initiation Protocol (SIP) is an IETF-defined signaling protocol, widely used for controlling
multimedia communication sessions such voice and video calls over Internet protocol (IP). The
protocol can be used for creating, modifying and terminating two-party (unicast) or multiparty
(multicast) sessions consisting of one or several media streams. It is a text-based Application Layer
protocol.
But as many use NAT to communicate with the public networks, and the IP address and port
combination in SIP packets are needed for addressing, we must come up with an effective way to deal
with SIP NAT traversal. SIP ALG is an easy solution with which you are only required to enable SIP
ALG on NAT application in this router to easily experience the smooth SIP connection between private
networks and public networks or even in two private networks with your VoIP devices.