Nortel Networks NN43001-504 manual NAT Traversal feature, Network configurations

84System information

NAT Traversal feature

The NAT Traversal feature is used where the IP Phone (this includes the handsets) is located on the private side of the NAT router, while the rest of the Server resides on the public side.

To ensure correct deployment of the wireless handsets in this type of network configuration, most, if not all, of the WLAN equipment must reside on the private side of the NAT router.

Network configurations

The WLAN Handset 2212 has a VPN feature that enables an IPsec tunnel to a Nortel VPN Router, which is the only IPsec platform supported today. This feature alters some of the usual design recommendations for the telephony components, such as the WLAN IP Telephony Manager 2245. Usually, the WLAN IP Telephony Manager 2245 is placed in the same subnet with the handsets.

With the VPN feature enabled, the WLAN IP Telephony Manager 2245 now resides behind the VPN Router in a different subnet from the handsets; however, even though the same-subnet restriction has been lifted, it is still very important to locate the WLAN IP Telephony Manager 2245 as close to the handsets as possible. In this case, it is located immediately behind the VPN Router (and in the same subnet as the VPN Router). The VPN Router must also be located as close to the handsets as possible.

You can deploy the handsets behind a NAT router with no Security Switch, as shown in Figure 18 "VPN design over a Layer 2 network" (page 85). This configuration includes a Layer 2 switch, which can be any Layer 2 switch (for example, Nortel Ethernet Switch 450). No Layer 3 device, such as a router, can be located between the wireless handsets and the WLAN IP Telephony Manager 2245.

Nortel Communication Server 1000

WLAN IP Telephony Installation and Commissioning

NN43001-504 01.02 Standard

Release 5.0 15 June 2007

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