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Reliable Multicast Messaging

Messaging Technologies


Reliable Multicast Messaging (RMM) is a high-throughput low-latency transport fabric designed for one-to-many data delivery or many-to-many data exchange, in a message-oriented middleware publish/subscribe fashion. RMM exploits the IP multicast infrastructure to ensure scalable resource conservation and timely information distribution.

Reliability and traffic control are added on top of the standard multicast networking. RMM takes this one step further and enables the support of highly available multicast data distribution, by implementing a number of stream failover policies that allow seamless migration of multicast transmission from failed to backup processes.

RMM includes two extensions that provide services not supported by the core RMM, LOT and RUM. Large Object Transfer (LOT) allows the multicast of files and large memory buffers. Reliable Unicast Messaging (RUM), a modification of RMM to use regular TCP transport instead of multicast, supports high-throughput low-latency data delivery on point-to-point links.

The Reliable Multicast Messaging (RMM) project is aimed at developing a comprehensive solution to provide multicast support both within the current IBM messaging framework and the emerging next generation framework and products.

RMM technology is integrated in WebSphere Front Office for Financial Markets v1, WBI Event Broker and Message Broker v5 and v6, WebSphere HAManager v6 released products.

RMM has been released by IBM as a standalone product, called WebSphere MQ Low Latency Messaging.