1. At least one computer readable storage medium comprising instructions that when executed enable a system to: receive, in a rendezvous server, a first registration message from a first registrar of a first network domain, the first registration message including a first device roster of a plurality of first devices of the first network domain; receive, in the rendezvous server, a second registration message from a second registrar of a second network domain, the second registration message including a second device roster of a plurality of second devices of the second network domain; and generate a first rendezvous point based at least in part on a plurality of key management server identifiers each associated with a key management server of the first and second network domains, the first rendezvous point to enable the plurality of key management servers to perform key management exchange to generate at least one group key for communication between at least some of the first devices of the first network domain and at least some of the second devices of the second network domain.