Campus Phone Book software developed for, and originally used at, the Computer Services Office of the University of Illinois at Urbana-Champaign. The server software is known as "qi" and the client is "ph". Recent versions of the software refer to CCSO (Computing & Communications Service Office).
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Nearby terms: CSMA/CD « CSMP « CSNET « CSO » CSP » CSP/80 » CS/PCode