Printer MIB
The SNMP object tree that lets any monitoring station ask any printer how much toner is left.
Before RFC 1759 landed in 1995, every manufacturer had a private MIB, and monitoring a mixed estate meant one tool per brand. The standard instead defined common objects for the things anyone actually wants to know: page counters, the state of each paper tray, consumable levels, jams, the text on the front panel, and an alert table. RFC 3805 revised the model in 2004.
This is the model behind print management software billing by the page, ordering toner before it runs out, and raising an alert about an empty tray in another building — all without knowing what brand the printer is. IPP has since grown its own attributes covering much of the same ground, but fleet monitoring still tends to ask over SNMP, for the boring reason that it already did when the printers were bought.