Definition - What does Interface Message Processor (IMP) mean?
The interface message processor (IMP) was the first packet-router. It was part of the ARPANET, the the precusor to today's Internet. IMPs monitored network status and gathered statistics. They were also the heart of the ARPANET from its launch until it was decomissioned in 1989. They also represent the first generation of the gateways that are now known as routers.
The interfact message processor proviced an interface to the ARPANET that was independent and could be used by any system. This laid the groundwork for the modern Internet and the network architecture that makes it possible.
A contract for the development of IMP was awarded to consulting company Bolt Baranek and Newman in 1968. What they developed essentially consisted of long-distance leased telephone circuits between pairs of IMPs. Host computers were connected to the IMP at the host site and network users were connected to their local host. A set of procols specified the conventions for communication between hosts connected to different IMPs.