I found what I was looking for on:
http://info.cern.ch/hypertext/WWW/AccessAuthorization/Overview.html
This is ideal :)
Paul
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** Paul Wain, (X.500 Project Engineer & WWW/httpd person), Computer **
* Centre, Brunel University, UXBRIDGE, Middlesex UB8 3PH, ENGLAND *
** E-MAIL: Paul.Wain@brunel.ac.uk **
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