NAT with deterministic IP address and port mapping

You can configure deterministic NAT mapping for NAPT44. Deterministic NAT mapping ensures that a given internal IP address and port are always mapped to the same external IP address and port, and the reverse mapping of a given translated external IP address and port are always mapped to the same internal IP address. Deterministic NAT mapping eliminates the need for logging address translations. Configure deterministic NAT translation in a NAT rule by including the translation-type deterministic-napt44 statement at the [edit services nat rule rule-name term term-name then translated] hierarchy level. Configure the range low value to be at least 1024 and the range high value to be no more than 65,535 at the [edit services nat pool pool-name port] hierarchy level. If you configure any ports below 1024, they are readjusted. You can configure up to 64,512 ports to make available for each internal subscriber with the deterministic-port-block-allocation block-size block-size statement at the [edit services nat pool pool-name port] hierarchy level. If you do not include this statement, the default value is 512. If you configure the block-size as 0, Junos OS automatically calculates the block size by using the number of configured subscriber IP addresses, the number of external translated IP addresses, and the port range.