Alg - 3Com OfficeConnect 3CRWDR200A-75 User Manual

4 In IP Range From, type the starting IP address of the IP address range
that your ISP assigned to you.
5 In To, type the ending IP address of the IP address range.
Figure 57 The ALG Screen

ALG

An Application Layer Gateway (ALG) is a SIP Back to Back User agent
(B2BUA). An ALG can be used to allow firewall traversal with SIP. If the
firewall has it's SIP traffic terminated on an ALG then the responsibility
for permitting SIP sessions is passed onto the ALG instead of the
firewall.
It supports access control restrictions, authentication, encryption, etc.
Application layer gateways can be made for all application level
protocols. They can be used for access control, but also for inter-
networking, for example between IPv4 and IPv6.
Session Initiation Protocol (SIP) is a protocol developed by the IETF
MMUSIC Working Group and proposed standard for initiating,
modifying, and terminating an interactive user session that involves
multimedia elements such as video, voice, instant messaging, online
games, and virtual reality.
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