How many concurrent NAT sessions are supported in Cisco IOS NAT? A: The NAT session limit is bounded by the amount of available DRAM in the router. Each NAT translation consumes about 160 bytes in DRAM. As a result, 10,000 translations (more than would generally be handled on a single router) would consume about 1.6MB. Therefore, a typical routing platform has more than enough memory to support thousands of NAT translations. " www.net130.com/technic/001/Cisco%20-%20NAT%20FAQ.htm"