AudioCodes Mediant 500L MSBR

User's Manual 15. Network
Version 6.8 159 Mediant 500L MSBR
15.6.1.2 Configuring NAT Translation per IP Interface
The NAT Translation table lets you configure up to 32 network address translation (NAT)
rules for translating source IP addresses per VoIP interface (SIP control and RTP media
traffic) into NAT IP addresses (global or public), when the device is located behind NAT.
This allows, for example, the separation of VoIP traffic between different ITSP’s, and
topology hiding of internal IP addresses to the “public” network. Each IP interface
(configured in the Interface table) can be associated with a NAT rule in this table,
translating the source IP address and port of the outgoing packet into the NAT address (IP
address and port range). The device's NAT traversal mechanism replaces the source IP
address of SIP messages sent from a specified VoIP interface to a public IP address.
If the device is configured with two network interfaces, for example, one LAN and one
WAN, only one NAT rule is required and without specifying ports. This rule is defined with
the network interface representing the WAN and with a public IP address. If the device is
configured with only one network interface (e.g., "Voice") and you have an SRD configured
for WAN and LAN, then you need to specify ports in order to differentiate between these
SRDs. In such a scenario, the device replaces the source IP address only for messages
sent from the WAN SRD, not from the LAN SRD.
The following procedure describes how to configure NAT translation rules in the Web
interface. You can also configure Bandwidth Profiles using the table ini file parameter,
NATTranslation or CLI command, voip-network NATTranslation.
 To configure NAT translation rules:
1. Open the NAT Translation Table page (Configuration tab > VoIP menu > VoIP
Network > NAT Translation Table).
2. Click Add; the following dialog box appears:
Figure 15-11: NAT Translation Table Page
3. Configure a NAT translation rule according to the parameters described in the table
below.
4. Click Submit, and then save ("burn") your settings to flash memory.
Table 15-16: NAT Translation Table Parameter Descriptions
Parameter Description
Index
CLI: index
[NATTranslation_Index]
Defines an index number for the new table record.
Note: Each table row must be configured with a
unique index.