(APNIC 28 - APOPS) Careful planning is needed for introducing NAT, by Hiroyuki Ashida of iTSCOM

Presented at JANOG24 in July 2009. At Janog22 the technologies and implications of introducing NAT into an ISP/SP infrastructure was raised and discussed. Now an organized planning effort for LSN (Large Scale NAT, previously known as Carrier Grade NAT) deployment is required to cope with IPv4 address depletion. Also it should be noted that LSNs need to be deployed before IPv4 depletion occurs, because it requires global IPv4 addresses. In this environment, I will evaluate how many resources would be required for actual LSNs and their ancillary facilities through a quantitative analysis of some of the elements such as port number restrictions and logging issues. The presentation will also include topics such as the impact for operation and usage after NAT deployment and consideration of assigning address space to subscribers.