IPv6 Prefix-NAT Calculator

LinkProof provides the IPv6 Prefix-NAT Calculator to predict the outcome of an internal IPv6 address (that is, a ULA), passing through the LinkProof device and being translated to a GUA. The calculator is needed to calculate the external router IPv6 address-especially when the internal prefix is different from the external router prefix. Using the IPv6 Prefix-NAT calculator is extremely important when working with predefined IPv6 addresses (such as external VRRP addresses).

Note	Although Radware recommends adopting the IPv6 ULA concept as detailed in the RFC, the IPv6 Prefix-NAT calculator also supports internal public IPv6 address of the 2000::/3 (Global Unicast range).

There can be two cases where the prefix of the internal address is translated to the prefix of the external IPv6 address.

Case 1 — The internal prefix is identical to the external-router prefix. It is simple to understand and manually calculate the result IP address (that is, the public IPv6 address) that will be seen by the Internet as the source of the internal packet. The replacement happens on each IPv6 source address passing through the LinkProof device that the IPv6 Prefix-NAT policy identifies.

Case 2 — The internal prefix is different from the external-router prefix. Here, calculating the result IP address (that is, the public IPv6 address) is complex; it involves several mathematical calculations. The IPv6 Prefix-NAT calculator can do the calculation for you.

The IPv6 Prefix-NAT calculator works only in CLI.

Syntax:

lp smartnat ipv6nat calc <LocalIPv6Addr> <RouterIPv6InternalAddr> <RouterIPv6Prefix>

where:

<LocalIPv6Addr> is the local IPv6 address.

<RouterIPv6InternalAddr> is the router IPv6 internal address.

<RouterIPv6Prefix> is the router IPv6 prefix.

Example

lp smartnat ipv6nat calc fc00:1002:fc01:3000:2000::1001 2030:2020:1000:200::1000 55

Result:

The nat address is: 2030:2020:1000:200:2000::1001