### NAT

Network Address Translation (NAT) usage can lead to problems that affect the consistency of addressing throughout your network. All H.323 IP Telephones support NAT interworking. Support for NAT does not imply support for Network Address Port Translation (NAPT). The telephones do not support communication to the PBX through any NAPT device.

NAT requires specific administration on the media server. A direct Avaya IP Telephone-to-Avaya IP Telephone call with NAT requires Avaya Communication Manager Release 3.0 or greater software. For more information, see Administration for Network Connectivity for Avaya Communication Manager (Document Number 555-233-504) on the Avaya support Web site.