Rai MS is a Link-State based protocol for the construction of Pub/Sub messaging services which allows for loops and redundancies in the network connections between systems. It has, at present, 4 different types of network transports:
-
OpenPGM based multicast, with an unicast inbox protocol.
-
TCP point to point connections.
-
Mesh TCP all to all connections.
-
Local bridging compatible with RV, NATS, Redis.
The first 3 transports may be interconnected with redundancies. The local bridging transports strips or adds the meta-data of the message that allows for routing through the network, so it can't be looped.
It uses a best effort delivery system. It serializes messages based on subject so that streams are delivered in order discarding duplicates, but messages which are lost in transit because of node or network failures, are not retransmitted.
The Rai Multicast Services Guide (or in html) describes the protocol, operating procedures, and architecture in more detail.