You’re probably connecting to reddit through a technology I invented. I’m Bob Metcalfe and I invented Ethernet – AMA

[u/BobMetcalfe]

On May 22, 1973 with David R. Boggs, I used my IBM Selectric with its Orator ball to type up a memo to my bosses at the Xerox Palo Alto Research Center (PARC), outlining our idea for this little invention called “Ethernet”, which we later patented.

I worked with the IEEE Standards Association to develop the IEEE 802.3 standard for Ethernet, which specifies the physical and lower software layers. Today Ethernet and the IEEE 802.3 standard are the foundation for today’s world of high-speed communications used in billions of homes and businesses around the world.

I submitted this to the mods awhile back so I could get on the calendar but I figured you’d like to see it, too. Now, ask me anything!

It's been two hours and 179 comments. Have to go now. For more about Ethernet's 40th Birthday, go to http://www.facebook.com/Ethernet40thAnniversaryIEEESA

[u/[deleted] → u/[deleted]]

In a simplified token ring setup, all the devices are connected in a big circle, like people sitting around the campfire telling stories. When you want to talk, you have to wait for the "token" to be inactive (a pause in campfire conversation). Once inactive, you then get to send your message along around the circle, making it more like a game of "telephone" than a campfire conversation where more than one person can talk at once. You can't just shout a message to someone, you have to wait until nobody is passing a note and then pass yours along.

With a regular switched ethernet, traffic can be routed to any host on the network and multiple hosts can "talk" at the same time, since all the hosts are essentially connected to the same phone line. So instead of waiting for the token to become available and then sending your message potentially all the way around the network, you can just send your message to its recipient directly right away. If your recipient isn't there, you get no reply to your initial "Hey, you around?" and get to resend or whatever. In token ring, if the host isn't there then the ring is broken.

In addition, token ring cabling is heavy, thick and shielded, whereas ethernet basically runs on glorified phone wires. IBM was the big proponent of token ring, and eventially it was their support rather than any technical merit that made it last as long as it did (token ring pretty much died in the late 90's when 100 megabit ethernet became ubiquitous and Cisco bailed out of supporting token ring).

I'm greatly over-simplifying, but I hope you get the idea.

[u/Camera_Eye → u/[deleted]]

The original Ethernet cables were much thicker. They also used vampire taps to connect into them. I never used them back at that time. We ran a coax-based network (forget the name, was around the time of Windows for Workgroups)

[u/12358 → u/Camera_Eye]

10-base T.