Managing IMAP

IMSP

IMSP is an Internet protocol that allows application programs to store program options and user information—such as personal and shared address books—on a remote network server. IMSP thus provides retrieval of client configuration information, which is traditionally stored on local disk, from anywhere on the network.

The original IMSP specification was written by members of the Project Cyrus team at CMU. The first IMSP server was released in 1994, also by CMU. Development of IMSP ceased in 1995, when it became evident that there was a need for a protocol to store client preferences that applied to other types of Internet applications, not just email. At that point, IMSP was reengineered and renamed Application Configuration Access Protocol (ACAP). ACAP is discussed later in this chapter. IMSP never made it into the standards track; its status is that of “experimental draft.” Despite its experimental status, IMSP is still alive and well, in use in production environments at over 1,000 sites, with more than one million end users. Because there are still very few ACAP-capable MUAs and ACAP servers, IMSP is still a good option for email client configuration storage. There are both stable IMSP clients and servers, and the protocol has been proven to work.

IMSP Specification

The IMSP Internet Draft is available from CMU at http://asg.web.cmu.edu/cyrus/rfc/imsp.html.

Cyrus IMSP Server

The recommended IMSP server is the CMU’s freely available Cyrus IMSP server, Version 1.6a1. ...