Internet Video Series, Part 2

 

Episode 18, Segment 04 of 06

Faced with this problem, the early Internet designers came up with a clever mechanism that they named the - "Address Resolution Protocol", or - " ARP " .

The movies in our - "Ethernet Series" - explained that Ethernet uses a - "broadcast" - mechanism, and that modern Ethernet Switches try to minimize broadcast traffic by limiting transmissions over unrelated interfaces. However, even in modern Ethernets in which old-fashioned - "Hubs" - have been replaced with Ethernet switches, some tasks work better if Ethernet frames are broadcast to every Ethernet interface that can be reached on the local network. Address Resolution Protocol takes advantage of this "broadcast" facility, and all ARP messages are broadcast to all local Ethernet interfaces. The protocol works so well that it has become completely automatic and virtually invisible to ordinary users. You should never need to configure, install, or remove any ARP components of your modern operating system. We are including this movie on ARP only to help you understand how your network works. (This information may also be helpful to you if the ARP logic of your local network is ever attacked by a hostile insider, who may be able to use it to subvert your Ethernet switches).


Episode 18, Segment 05 of  06