network service
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... X.500 DSA interface to XNS (Xerox Network Services) Clearinghouse
directory to provide access to Xerox Corporation's Clearinghouse via
X.500 ...
... network protocol suite to provide Mail, Filing,
Directory, Authentication, etc. network services for the installed
based of 45,000+ Xerox workstations. The Directory is based on the
XNS Clearinghouse protocol which is similar to X.500 ...