It is a network to explore routing technologies used in the Internet and tries to establish direct non-NAT-ed connections between the members.
While OSPF is the most commonly used protocol for intra AS routing, each participant is free to choose any other IGP, like Babel, inside their AS.
Over time, this has been replaced by WireGuard, partly due to faster performance and simpler configuration.
[19] Note that other private address ranges may also be announced in dn42, as the network is interconnected with other similar projects.
[22] In order to use BGP, even in a private environment, autonomous system numbers are needed.
The most commonly used BGP implementations used in dn42 are BIRD and FRR, but some participants use OpenBGPD, XORP, GoBGP or the implementation of JunOS, Cisco IOS, MikroTik's RouterOS or VyOS (which uses FRR as a routing daemon in the background).
WireGuard is most commonly used for this, as it is easy to configure and is considered secure (with Perfect Forward Secrecy).
To ensure uniform administration of IP addresses and domains, there is also a registry in dn42, as in Clearnet.
One of the registry maintainers then looks at this, validates it (including syntactically) and also verifies it (checking the authorization and signature).
[30] The dn42 maintains a number of links to similar projects:[31] The dn42 has its own (unofficial) Certificate Authority (CA).