Interface Message Processor

computing

Also known as: IMP

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Last updated

July 23, 2026

Quick Summary

The Interface Message Processor (IMP) was a crucial component in the development of early computer networks, most notably the ARPANET. The IMP was essentially a dedicated minicomputer that acted as a gateway, connecting host computers to the network. It utilized the innovative technology of packet switching, which breaks down data into smaller packets for independent transmission and reassembly at the destination. This allowed for more efficient and robust communication compared to traditional circuit-switched methods. The IMPs were developed by Bolt, Beranek, and Newman (BBN) and were instrumental in establishing the first host-to-host network connection in 1969, laying the groundwork for the modern Internet.123

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Robert Kahn
…group that designed the network’s Interface Message Processor, which would mediate between the network and each institution’s host computer. Second, and perhaps more important, in 1972 Kahn helped organize the first International Conference on Computer Communication, which served as the ARPANET’s public debut.
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…group that designed the network’s Interface Message Processor, which would mediate between the network and each institution’s host computer. Second, and perhaps more important, in 1972 Kahn helped organize the first International Conference on Computer Communication, which served as the ARPANET’s public debut.
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Leonard Kleinrock
…connected a packet-switching computer, the Interface Message Processor (IMP), to a SDS Sigma 7 computer, which became the first node on ARPANET, which was originally planned to have four nodes. On October 29, 1969, Kleinrock and his student Charley Kline sent the first message over ARPANET to an IMP and…
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…connected a packet-switching computer, the Interface Message Processor (IMP), to a SDS Sigma 7 computer, which became the first node on ARPANET, which was originally planned to have four nodes. On October 29, 1969, Kleinrock and his student Charley Kline sent the first message over ARPANET to an IMP and…
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Lawrence Roberts
…handled by smaller computers called interface message processors (IMPs) rather than the large mainframes that would be the nodes of ARPANET. Roberts modified the ARPANET plan to incorporate Clark’s suggestion. On October 29, 1969, American computer scientist Leonard Kleinrock and his student Charley Kline sent the first message over ARPANET…
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…handled by smaller computers called interface message processors (IMPs) rather than the large mainframes that would be the nodes of ARPANET. Roberts modified the ARPANET plan to incorporate Clark’s suggestion. On October 29, 1969, American computer scientist Leonard Kleinrock and his student Charley Kline sent the first message over ARPANET…
Read More