This is an quick update on my work on LibreNet6 and LibreMesh within the last weeks. The exam period in Tokyo started and I had a cold which slowed me a bit down, once both passed I will focus with doubled concentration on the project again!
Multiple servers
The approach of using Tinc allows the usage of more then one IPv6 server, allowing to connect the servers of multiple communities with different IPv6 subnets. Babeld automatically detects where to route traffic when using external subnetworks. This is fortunate as it is possible that there is a high latency between mesh gateway and IPv6 server which would slow down traffic. However, using Tinc and babeld I ran a setup with two mesh gateways both using two different IPv6 subnets. While pings to the other network had high latencies at first (me in Tokyo, one IPv6 server in London and one in Argentina), Tinc automatically exchanged the IPv6 addresses of the mesh gateways which then could connect directly, lowering the latencies. Summarizing this experiment, using Tinc makes the network independent of the public IPv6 addresses.
No lime-app plugin
Initially I though of creating a lime-app plugin which allows to easily requests access to a Tinc mesh. However, after an evolution with my mentor and reading more about Tinc, we decided against it: The new 1.1 release of Tinc not only simplifies joining a mesh by offering the invite and join commands, but also allows to do all configuration automatically with the help of an invitation file. These new features simplify the project much more then I though, following the Spanish documentation on Altermundi.
Adding some security
As mentioned above some parts where easier as excepted, I though of looking into additional tasks for the project. Currently the usage of babeld requires all users of the mesh to fully trust one another as babeld does not provide any security (I could find) regarding announced routes. Mesh routing with security is offered by BMX7, which introduces a model to set (dis)trust between nodes. For this reason I’ve been in contact with Axel Neumann, the developer of BMX7, to fix an long standing error in OpenWrt which lead to false MTU rates in BMX7. The fix was merged upstream and thereby allows to test BMX7 over Tinc as a secure babeld alternative.
English documentation
Beneath the experiments I’ve started to translate (and simplify) the Spanish documentation of LibreNet6 and will upload it to the GitHub repository once finished. Important part is also how to configure 6to4 tunnels as surprisingly few VM providers offer any IPv6 connectivity per default but only a single public IPv4 address.