How to circumvent the restrictions of DS-Lite

Internet providers are increasingly moving towards only providing customers with pure IPv6 connections (DS Lite or CGN). However, the i-telex software is only IPv4-compatible. This applies not only to pure Internet communication, but also to the underlying database structures for TNS, etc. IPv6 capability for i-telex is currently not in sight.

With DS-Lite, all carrier internal traffice is done via IPv6; transition to IPv4 network is done at the carrier borders. That means that your router is not reachable from the IPv4 part of the internet, and also your piTelex device is not. To make piTelex reachable externally in this case, there are different approaches:

Centralex

This option enables users without a public IPv4 address to participate in the i-Telex network. If this option is activated, the i-Telex establishes a dedicated connection to a switching server equipped with an IPv4 address. Every incoming connection is then “forwarded” via this server. The switching server is also often called Centralex.

[!IMPORTANT] Luckily, piTelex now supports the Centralex protocol in (already very well working) beta test mode. It is not yet available in the master branch, but in the branch "testing". You are encouraged to test this version and report your experiences.

Look here for description and configuration options.

Use tunneling software

Because centralex is not implemented in piTelex yet, we have to find a different solution. Goal is to tunnel the piTelex IPv4 packets over an IPv6 network, i.e. encapsulate the piTelex-packets in a IPv6 transport.

There are commercial service provider on the market for this, but there is also a DIY solution for this.