User's Manual

Chapter 9 Network Address Translation (NAT)
P-2612HW Series User’s Guide
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The following table describes the fields in this screen.
9.4.2 SIP ALG
A SIP Application Layer Gateway (ALG) allows SIP calls to pass through NAT by
examining and translating IP addresses embedded in the data stream. When the
ZyXEL Device registers with the SIP register server, the SIP ALG translates the
ZyXEL Device’s private IP address inside the SIP data stream to a public IP
address. You do not need to use STUN or an outbound proxy if your ZyXEL Device
is behind a SIP ALG.
Table 48 Network > NAT > Address Mapping > Edit
LABEL DESCRIPTION
Type Choose the port mapping type from one of the following.
One-to-One: One-to-One mode maps one local IP address to one global
IP address. Note that port numbers do not change for One-to-one NAT
mapping type.
Many-to-One: Many-to-One mode maps multiple local IP addresses to
one global IP address. This is equivalent to SUA (i.e., PAT, port address
translation), ZyXEL's Single User Account feature that previous ZyXEL
routers supported only.
Many-to-Many Overload: Many-to-Many Overload mode maps multiple
local IP addresses to shared global IP addresses.
Many-to-Many No Overload: Many-to-Many No Overload mode maps
each local IP address to unique global IP addresses.
Server: This type allows you to specify inside servers of different services
behind the NAT to be accessible to the outside world.
Local Start IP This is the starting local IP address (ILA). Local IP addresses are N/A for
Server port mapping.
Local End IP This is the end local IP address (ILA). If your rule is for all local IP
addresses, then enter 0.0.0.0 as the Local Start IP address and
255.255.255.255 as the Local End IP address.
This field is N/A for One-to-One and Server mapping types.
Global Start
IP
This is the starting global IP address (IGA). Enter 0.0.0.0 here if you have
a dynamic IP address from your ISP.
Global End IP This is the ending global IP address (IGA). This field is N/A for One-to-
One, Many-to-One and Server mapping types.
Server
Mapping Set
Only available when Type is set to Server.
Select a number from the drop-down menu to choose a port forwarding
set.
Edit Details Click this link to go to the Port Forwarding screen to edit a port
forwarding set that you have selected in the Server Mapping Set field.
Back Click Back to return to the previous screen.
Apply Click Apply to save your changes to the ZyXEL Device.
Cancel Click Cancel to begin configuring this screen afresh.