The Internet White Pages Service (IWPS) has been slow
to materialise for many reasons. One of them is the
security concerns that organisations have, over allowing
the public to gain access to either their Intranet or their
directory database. The Directory Guardian is a firewall
application proxy for X.500 and LDAP protocols that is
designed to alleviate these fears. Sitting in the firewall
system, it filters directory protocol messages passing into
and out of the Intranet, allowing security administrators
to carefully control the amount of directory information
that is released to the outside world. This paper describes
the design of our Guardian system, and shows how
relatively easy it is to configure its filtering capabilities.
Finally the paper describes the working demonstration of
the Guardian that was built for the 1997 World
Electronic Messaging Association directory challenge.
This linked the WEMA directory to the NameFLOWParadise
Internet directory, and demonstrated some of
the powerful filtering capabilities of the Guardian
