maintenance operations protocol (DEC) (MOP)

Digital Equipment's Maintenance Operations Protocol (MOP) is a proprietary protocol for testing and maintenance tasks in the DECnet architecture.

The MOP protocol dates back to the 1970s and is located at the network layer. The MOP protocol supports various services such as uploading and downloading of the system software, furthermore remote testing and diagnostic functions.

The MOP frames contain commands for the request for loading data, the memory addresses for the data and the parameters, requests for rebooting, the program, the counter status or for the identification of the remote system.