protomask/docs/website/content/_index.md

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Protomask

What is protomask?

Protomask is a user space NAT64 implementation geared towards networks that need fast and reliable inter-protocol packet translation. Behind the scenes, protomask uses the Universal TUN/TAP Device Driver to translate incoming packets from IPv4 to IPv6 and vice-versa.

The protomask tool suite

To accomplish the various translation needs of an IPv6-only or dual-stack ISP, the protomask tool suite includes a few tools:

• protomask: The main NAT64 daemon
  • Translates IPv6 packets using RFC6052 IPv4-Embedded IPv6 Addressing to native IPv4 traffic
  • Can handle high volumes of traffic from multiple clients simultaneously
• protomask-clat: A Customer-side transLATor (CLAT) implementation
  • Intended to be deployed at the customer edge to pass IPv4 traffic over an IPv6-only ISP's network

Every tool in the protomask suite is easy to deploy and configure, plus supports optionally exposing Prometheus metrics for remote monitoring.

The protomask library suite

The development of protomask necessitated the creation of a few specialized software libraries. Since the technology developed for protomask is useful outside of the scope of this project, these libraries are also available for general use:

• easy-tun: A minimal TUN interface library
• fast-nat: A library designed for highly efficient mapping and lookup of IP address pairs
• interproto: The heart of protomask, a library for translating many types of packets between layer 3 protocols
• rfc6052: A Rust implementation of RFC6052
• rtnl: A high-level wrapper around rtnetlink

Want to learn more?

Check out the documentation for a deeper dive into protomask, or head over to the GitHub repository to see the source code.