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  1. Hi Rene,

    I’m trying to configure nat64 but apparently the ios I’m using does not recognize these commands. just to confirm it is it because of the IOS version or do i need to enable anything?

    the ios i’m using is : BOOTLDR: 7200 Software (C7200-ADVIPSERVICESK9-M), Version 15.1(4)M5,

  2. Hi Rene, correction:

    R2(config)#interface GigabitEthernet 2

    your diagram shows FastEhternet interfaces but in the configuration you are saying GigabitEthernet.

  3. Hello Stuart

    For the most part you are correct that NAT64 has a limited usage in real world applications. However, there are cases where it is necessary. Also, it is supported by Cisco IOS-XE 15.1(3)S4 as well as Cisco ASA 9.1 and later.

    Running two protocols in parallel always requires more management overhead, and if it can be avoided at all, it is good to do so. Unfortunately, it’s not always possible.

    I hope this has been helpful!


  4. Hello Chris

    Yes, such a configuration would work, assuming you want to translate the other way around.

    I hope this has been helpful


  5. Hello sales2161

    Well, it all depends on your point of view. :stuck_out_tongue:

    When we talk about NAT in IPv4, we traditionally talk about “real” and “fake”, public and private, routeable and non-routable addresses because we are translating for the purpose of conserving addresses. So there is a meaning to these terms. However, NAT in a more general sense is a translation from one IP address range to another, regardless of whether the addresses are private, public, routable or not. You could translate from to for example. In such a case, which is fake and which is real? It depends on your point of view.

    When we apply this to NAT64, what we are doing is translating between address spaces of two different protocols. Which is real or which is fake depends on the application, on which side of the NAT64 router is facing the Internet and which is not (maybe neither is facing the Internet).

    So if we use the conventions of the terminology, then yes, you are correct, the IPv6 address will be fake and the IPv4 will be real. But looking at it in a broader sense, it just becomes a translation in the opposite direction.

    I hope this has been helpful!


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