Description of the illustration ''%s''cass_logical

This figure shows the Cassandra message store logical architecture. The front-end hosts, which can be Messaging Multiplexor (MMP), LMTP client, or Webmail (mshttpd) hosts, communicate with the message access hosts, which run the imapd and LMTP server processes. The message access hosts also run the Event Notification Service (ENS) enpd process for horizontal scalability. The message access hosts then communicate with a Cassandra datacenter, which consists of multiple Cassandra database hosts.