User's Manual

SIP_ALG

Select Enable 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.

IGMP

IGMP, known as Internet Group Management Protocol, is used to management hosts from multicast

group.

IGMP Proxy: Accepting multicast packet. Default is set to Disable.

IGMP Snooping: Enable or disable the IGMP Snooping function. Without IGMP snooping, multicast

traffic is treated in the same manner as broadcast traffic - that is, it is forwarded to all ports. With

IGMP snooping, multicast traffic of a group is only forwarded to ports that have members of that

group.”