The CCSO Ph directory — the campus phone-book protocol that predated LDAP, now essentially extinct.
Ph is the client protocol for the CCSO nameserver built at the University of Illinois, formalised in RFC 2378: a client sends text commands like "query smith return email phone" and the qi server answers with typed field data about people. Universities ran it as the campus directory through the 1990s, and mail clients shipped Ph lookup support before LDAP won. IANA registered 481 as the Ph service to the RFC's author, though many deployments answered on 105 instead. Any listener today is a museum piece.
Expose with care
A cleartext directory of names, phone numbers and email addresses that answers anonymous queries — exactly the bulk personal data you do not want scraped from a public IP.
$ printf 'quit\r\n' | nc -v -w 5 TARGET 481Seen this on your network? Beige Box scans your Wi-Fi and shows every open port on every device — and its Ports tool links straight back here.
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