Cluster Communication Through Message Server

The SAP architecture uses Message Server for handling cluster communication instead of each node contacting with every other node. 


Had each node been designed to talk to every other node, it would need an open connection per node (point-to-point network was used in 6.20 architecture). For such a setup, the required number of connections would be n*(n-1)/2. The number of connections (network overhead) would increase as a quadratic function of the number of nodes.


By using Message Server as the central service (star network) for cluster communication, the number of connections would be n, making it a linear function of the number of nodes.

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