MAP is an open source CPE implementation of draft-ietf-softwire-map and draft-ietf-softwire-map-t. It runs on Linux and Openwrt.

MAP is a mechanism for transporting IPv4 packets across an IPv6 network using IP translation (MAP-T) or encapsulation (MAP-E), and a generic mechanism for mapping between IPv6 addresses and IPv4 addresses and transport layer ports. It is defined in https://datatracker.ietf.org/doc/draft-ietf-softwire-map/ and https://datatracker.ietf.org/doc/draft-ietf-softwire-map-t/

A typical MAP use case is shown in the Figure below.

                   User N
                Private IPv4
               |  Network
               |
            o--+---------------O
            |  |  MAP CE       |
            | +-----+--------+ |
            | NAPT44|  MAP   | |
            | +-----+      | | |\    ,--------,                        ,~-----------,
            |       +--------+ | \ ,'          '.                    ,'              `,
            O------------------O  /              \   O---------O    /                  \   
                                 |   IPv6 only    |  |   MAP   |   /       Public       \
                                 |    Network     |--+  Border +- (         IPv4         )
                                 |  (MAP Domain)  |  |  Relay  |   \       Network      /
            O------------------O  \              /   O---------O    \                  /
            |    MAP   CE      |  /".          ,'                    `.              ,'
            | +-----+--------+ | /   `----+--'`                         '-----------'
            | NAPT44|  MAP   | |/
            | +-----+        | |
            |   |   +--------+ |
            O---.--------------O
                |
                 User M
              Private IPv4
                Network

This implementation is used on MAP CE and can be configured with/without NAPT44 function. The interoperation between this implementation and Cisco ASR 1K/9K has been tested successfully with either encapsulation mode or translation mode. See https://blogs.cisco.com/sp/real-world-demonstration-of-map-for-ipv6/ for more details.

Moreover, we have tested the CE implementation in CERNET/CERNET2 environment and the result shows that a unified MAP CE can be configured to support MAP-T, MAP-E, and backward compatible with stateless NAT64, stateful NAT64 and dual-stack lite. Please refer to https://datatracker.ietf.org/doc/draft-xli-softwire-map-testing for further reading.

In the repository, the directory 'modules' contains the code for generating the MAP kernel module, while the directory 'utils' contains an utility to configure MAP parameters. You can read 'readme' for the detailed usage of the utility.

As four examples, script files 'zyhgw-T44' and 'zyhgw-T' show how to configure the translation mode with/without NAT44; while 'zyhgw-E44' and 'zyhgw-E' show how to configure the encapsulation mode with/without NAT44. To stop the module, just execute the script file 'stopall'.