Federizer is an intermodal (push/pull) Message Transfer Agent (iMTA) that transfers arbitrary messages from one
computer to another using the gRPC framework. The iMTA uses a client authentication mechanism — mTLS certificate-bound access tokens issued by the Security Token Service (STS) — to convey the user's security context alongside messages between computers. This concept is generally applicable to store-and-forward and cut-through forwarding systems. In the long run, Federizer may be suitable as a potential replacement for current SMTP MTAs.