Nat Parameters - AudioCodes Mediant 1000B User Manual

User's Manual

59.2.6 NAT Parameters

The Network Address Translation (NAT) parameters are described in the table below.
Parameter
NAT Parameters
NAT Mode
disable-NAT-
traversal
[NATMode]
NAT IP Address
nat-ip-addr
[StaticNatIP]
[NATBindingDefaultTimeo
ut]
Version 7.0
Table 59-14: NAT Parameters
Enables the NAT feature for media when the device communicates with
UAs located behind NAT.

[0] Enable NAT Option = NAT traversal is performed only if the UA
is located behind NAT:

UA behind NAT: The device sends the media packets to the IP
address:port obtained from the source address of the first media
packet received from the UA.

UA not behind NAT: The device sends the packets to the IP
address:port specified in the SDP 'c=' line (Connection) of the
first received SIP message.
Note: If the SIP session is established (ACK) and the device (not the
UA) sends the first packet, it sends it to the address obtained from
the SIP message and only after the device receives the first packet
from the UA does it determine whether the UA is behind NAT.

[1] Disable NAT = (Default) The device considers the UA as not
located behind NAT and sends media packets to the UA using the IP
address:port specified in the SDP 'c=' line (Connection) of the first
received SIP message.

[2] Force NAT = The device always considers the UA as behind NAT
and sends the media packets to the IP address:port obtained from
the source address of the first media packet received from the UA.
The device only sends packets to the UA after it receives the first
packet from the UA (to obtain the IP address).

[3] NAT By Signaling = The device identifies whether or not the UA is
located behind NAT based on the SIP signaling. The device
assumes that if signaling is behind NAT that the media is also behind
NAT, and vice versa. If located behind NAT, the device sends media
as described in option [2] Force NAT; if not behind NAT, the device
sends media as described in option [1] Disable NAT. This option is
applicable only to SBC calls. If the parameter is configured to this
option, Gateway calls use option [0] Enable NAT Option, by default.
For more information on handling calls from UAs behind NAT, see 'First
Incoming Packet Mechanism' on page 157.
Defines the global (public) IP address of the device to enable static NAT
between the device and the Internet.
Note: For the parameter to take effect, a device reset is required.
The device sends SNMP keep-alive traps periodically - every 9/10 of
the time configured by the parameter (in seconds). Therefore, the
parameter is applicable only if the SendKeepAliveTrap parameter is set
to 1.
The parameter is used to allow SNMP communication with AudioCodes
EMS management platform, located in the WAN, when the device is
located behind NAT. It is needed to keep the NAT pinhole open for the
SNMP messages sent from EMS to the device.
899
59. Configuration Parameters Reference
Description
Mediant 1000B Gateway and E- SBC