Network Address Translation
Dlink DRO-220i User Guide
45
Session Initiation Protocol (SIP) packets have IP address embedded in the data packet. So
NAT is not fully effective for such applications. SIP ALG enables SIP phones on the
LAN side to make calls across the Internet when NAT is enabled.
The administrator needs to configure the port numbers used for SIP by the IP Phone or
the SIP Server. A maximum of 20 SIP calls can be active simultaneously.
L
Caution:
If router reboots, SIP Phones need to be reregistered with the external SIP
Server. This is because the router does not remember the earlier SIP Registrations on
reboot.
Select
NAT
→
SIP-ALG
to configure the
SIP ALG Configuration
as explained below.
SIP ALG Configuration
Enable
Select
Enable
to activate the feature.
Port number
Enter the port number of the SIP Phone or SIP Server.
After entering all the information press the
Apply
button and the
SIP ALG Table
will
now be displayed at the bottom. To delete an entry press the
Delete
button next to the
entry.
6.4
NAT Table
The router maintains a table of sessions for which IP Address and Port Translations have
been performed. This translation table can be viewed from the
NAT Table
Page.
Select
Status
→
NAT Table
to view the
NAT Session Table
explained below.
NAT Session Table
Private IP address:
Port
This is the IP address and port number of a host on the private LAN that
has an active NAT session.
Peer IP address:
Port
This is the IP address and port number of a host on the WAN that has an
active connection with the router.
Mapped IP address:
Port
This is the IP address and port number that will be seen by the devices on
the WAN side for the corresponding private IP address and port.
Web UI
Web UI
