In arpanet , a background program in the interface message processor ( imp . these programs include the statistics generation routines , the debug facilities , and the imp console teletype handler 在目的代码中安插的断点,使得执行在适当的时间和位置上转向查错程序。
The Interface Message Processor (IMP) was the packet-switching node used to interconnect participant networks to the ARPANET from the late 1960s to 1989. It was the first generation of gateways, which are known today as routers.