(
Session
Initiation
Protocol
Application-
Level
Gateway) A function in a router that allows VoIP packets to traverse the network's firewall. Because Internet-based telephony emerged so quickly, the SIP ALG function was often enabled by default in many consumer-based wireless routers. Because various implementations caused problems, the ALG setting later defaulted to "disabled." See
SIP,
SIP proxy and
STUN.
Turn It Off in the Router Control Panel
SIP ALG was disabled in order to allow VoIP calls to reach the PBX in this installation.
Is ALG On or Off?
If users cannot access their router's control panel to find out if ALG is turned on, this Windows utility from RingLogix does the job.