First Building Block of the Internet

Interface Message Processor (IMP) Front PanelAugust 30, 1969

The first Interface Message Processor (IMP) is delivered to Leonard Kleinrock’s research group at UCLA. The IMP was the device that would interconnect networks between research facilities on the developing ARPANET, the precursor to the Internet. As a packet-switching device, the IMP can be considered the first generation of what we now call network routers. The second IMP was delivered to the Stanford Research Institute on October 1, 1969 and the first message between the two IMPs was sent on October 29, 1969, which is now considered the first message ever sent on the Internet.