There is a central pool of Unix print servers, managed by the Athena Server Operations group. Printers served by this central pool can be managed by Operations and Help Desk staff. Any private Athena workstation can be configured as a print server to serve a private network or locally attached printers. LPRng is based on the BSD Line Printer spooling system architecture, and is mostly backwards-compatible with that system. It is a client-server system, with central queue management servers that can be isolated from clients.
Servers can control remote network printers, or local serial and parallel printers.
This can either be a plain file that the system reads, or some outside database, that the system searches via a callout program. The client and server printcap can be completely disjoint. The original protocol is described in RFC 1179. The protocol supports querying queues and removing a job from a queue before printing. When the server prints a job, it first looks up the printer's location in the server printcap database.