Chapter 10 NAT
LTE3301 Series User’s Guide
93
To enable and disable the SIP ALG in the LTE3301, click
Ne two rk > NAT > ALG
. The screen appears as
shown.
Fig ure 59
Network > NAT > ALG
The following table describes the labels in this screen.
10.6 Te c hnic a l Re fe re nc e
The following section contains additional technical information about the LTE3301 features described in
this chapter.
10.6.1 NATPo rt Fo rwa rding : Se rvic e s a nd Po rt Num b e rs
A port forwarding set is a list of inside (behind NAT on the LAN) servers, for example, web or FTP, that you
can make accessible to the outside world even though NAT makes your whole inside network appear
as a single machine to the outside world.
Use the
Po rt Fo rwa rding
screen to forward incoming service requests to the server(s) on your local
network. You may enter a single port number or a range of port numbers to be forwarded, and the local
IP address of the desired server. The port number identifies a service; for example, web service is on port
80 and FTP on port 21. In some cases, such as for unknown services or where one server can support
more than one service (for example both FTP and web service), it might be better to specify a range of
port numbers.
In addition to the servers for specified services, NAT supports a default server. A service request that does
not have a server explicitly designated for it is forwarded to the default server. If the default is not
defined, the service request is simply discarded.
Note: Many residential broadband ISP accounts do not allow you to run any server processes
(such as a Web or FTP server) from your location. Your ISP may periodically check for
servers and may suspend your account if it discovers any active services at your
location. If you are unsure, refer to your ISP.
Table 40 Network > NAT > ALG
LABEL
DESC RIPTIO N
ALG-SIP
Select
Ena b le
to make sure SIP (VoIP) works correctly with port-forwarding and address-
mapping rules. Otherwise, select
Disa b le
to turn off the SIP ALG.
Apply
Click
Apply
to save your changes back to the LTE3301.
Cancel
Click
C a nc e l
to begin configuring this screen afresh.