Source: Where Wizards Stay Up Late: The Origins of the Internet

Authors: Katie Hafner and Matthew Lyon

In chapter 8, Katie discussed the early solution to the problem of connecting networks built on different incompatible hardware. Vint Cerf thought of the idea of having a routing computer acting as a gateway between the two networks. That way a gateway could be programmed for any two networks and all it needed to understand was these two languages.

The idea here is similar to a group of people communicating who all speak a different language. It would be very hard, maybe impossible to find one person that could translate effectively between all the languages. Furthermore, what if a new person joined the conversation: the translator would have to be replaced with someone who spoke all the current languages plus the new one. A much simpler solution is to find translators that speak two languages and chain the conversation: Spaniard -> gateway translator (Spanish, German)  <- German <- gateway translator (German, Italian) <- Italian. If a new person was to join you could just find a new translator and put him into the conversation, which has no effect on the other gateways.

The concept of building a device to ‘translate’ incompatible technology coupled with the move to define standards for certain aspects of computer communication allowed for the Arpanet to grow into the internet we know today, where macs and pcs talk to each other without even knowing they are different species of hardware.