An Alternating Bit Protocol was used by the [[ARPANET]] and the [[Packet switching#EIN|European Informatics Network]].<ref>{{Cite book|last=Davies|first=Donald Watts|url=https://archive.org/details/computernetworks00davi|title=Computer networks and their protocols|date=1979|publisher=Chichester, [Eng.] ; New York : Wiley|others=Internet Archive|pages=[https://archive.org/details/computernetworks00davi/page/206 206]|url-access=registration}}</ref>
