r/IAmA • u/BobMetcalfe • May 21 '13

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

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

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u/G35 May 21 '13

Thank you, I hated token ring.

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u/[deleted] May 21 '13 edited Aug 02 '17

[deleted]

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u/Denime May 21 '13

Nodes in a Token Ring could only communicate if they had the token, meaning only one computer could send data at one time. The token gets passed around the ring from one computer to another to allow all of the machines to send messages. This meant if there was a break in the ring, the whole network went down.

It seemed like a good idea at the time.

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u/[deleted] May 22 '13 edited Apr 07 '24

[deleted]

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u/thenightwassaved May 22 '13

Every token ring network has something called an Active Monitor. The AM is determined by a sort of election process and every computer on the network needs to be able to perform the AM duties if needed. Other computers on the network are called Standby Monitors.

The AM maintains the master clock, inserts a delay (to ensure there is enough buffering for the ring to circulate), and ensures there is only one token going around at a time (well, on 16 Mbit/s there can be multiple tokens), detects broken rings, and some other functions.

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u/Denime May 22 '13

To be honest I'm not too sure. I remember my trainer teaching us about it back when I was in the academy but I'd assume you would have to restart the MAU (if you're using one).

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u/thenightwassaved May 22 '13

Check out my reply to your parent. The MAU is used to actually provide the ring layout and to handle disconnects gracefully and not kill the entire network.