The delegations tree is a recursively generated tree of basic (signed) delegations. All delegation zones in this tree are only hosted on one of the servers, specificed by the name in de *first* label of the zone's apex. Every zone has delegations to zones on each of the servers. The tree is three levels of delegations deep.
Currently, all the zones are signed with RSA-SHA1, and NSEC. We could make these for other types as well, should it be requested.