As our development and use of cyrus progressed, it became obvious that it would be necessary to add
horizontal scalability to the system. That is, be able to share the entire IMAP mailbox namespace, but distribute
the load amongst a pool of servers.
Hence, the CyrusMurder. This system uses a combination of IMAP servers, IMAP proxies, and a directory server
to provide a uniform view of the IMAP namespace to large number of users. This is different from traditional IMAP
proxies because any user can still select any mailbox, they are not limited to a particular subset of
the IMAP namespace.
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