Telegraphy the sense of a system that can transmit arbitrary messages over arbitrary distances. Lines of signalling relay stations can send messages to any required distance, but all these systems are limited to one extent or another in the range of messages that they can send. A system like flag semaphore, with an alphabetic code, can certainly send any given message, but the system is designed for short-range communication between two persons. An engine order telegraph, used to send instructions from the bridge of a ship to the engine room, fails to meet both criteria; it has a limited distance and
IBM System/36 workstation IDs, and so forth. The CNFIGSSP procedure was used to configure the system, including the devices. Each device is assigned a two-character ID. The first letter must be alphabetic; the second must be alphanumeric. The system also reserved certain IDs; you could not call your device I1 or F1, for example. I1 is the name of the diskette drive; F1 is what the system calls the hard drive (stands for "fixed disk," since it is not a removable disk pack.) CNFIGSSP is used to place devices on the line/address map; identify the particular IBM printer or terminal model; assign