M2M IDG500AM-0T001 User Manual page 103

M2M Cellular Gateway
A local user wants to make one call to the SIP Phone #2 by using the SIP Phone #1, the
NAT Gateway will monitor the calling process, open up required service ports for
incoming packets and make the address and port translation for the voice
communication.
First, the calling starts from the SIP Phone #1 to the SIP server. Then the SIP server
invites the SIP Phone #2 and finally, the SIP Phone #1 talks to the SIP Phone #2, as
shown in above diagram.
Special AP & ALG Setting
The Special AP setting allows some applications require multiple connections.
The ALG setting allows user to Support some SIP ALG, like STUN.
Enable Special AP and Virtual Computer
Go to Basic Network > NAT/ Bridging > Special AP & ALG tab
Special AP & ALG tab
Item
Special AP
ALG Enable
Save
Undo
Create/Edit Special AP
The router allows you to custom your Special AP rules. The router supports up to a maximum of 8
rule-based Special AP sets.
When Add button is applied Special AP Rule Configuration screen will appear.
Index skipping is used to reserve slots for new function insertion, when required.
Value setting
The box is checked by
default
The box is checked by
default
N/A
N/A
Description
Check the Enable box to activate this NAT function
Check the Enable box to activate this NAT function
Click the Save button to save the setting
Click Undo to cancel the settings
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