NPAP
The Network Printing Alliance Protocol (NPAP) was developed as a protocol for returning printer configuration and status via parallel, serial, network and later USB. In 1997, NPAP was approved as IEEE 1284.1 TIPSI. SNMP became the standard for network printer management, thus NPAP was never widely accepted. Lexmark appears to be the only manufacturer still supporting NPAP.
Read more about this topic: Printer Working Group