05.19
“….a towel has immense psychological value. For some reason, if a strag (strag: nonhitchhiker) discovers that a hitchhiker has his towel with him, he will automatically assume that he is also in possession of a toothbrush, washcloth, soap, tin of biscuits, flask, compass, map, ball of string, gnat spray, wet-weather gear, space suit etc., etc. Furthermore, the strag will then happily lend the hitchhiker any of these or a dozen other items that the hitchhiker might accidentally have “lost”. What the strag will think is that any man who can hitch the length and breadth of the galaxy, rough it, slum it, struggle against terrible odds, win through, and still knows where his towel is, is clearly a man to be reckoned with.”
I think that most of you will recognize that passage from the late author Douglas Adams, creator of the Hitchhikers Guide to the Galaxy series of works. Douglas Adams passed on May 11, 2001, and on Tuesday, May 25th, people around the world will honor the author by taking their towel with them wherever the day may take them. If you want to find some fellow hitchhikers to revel with or get some more history on the event, you can surf to www.towelday.org.
And if you’re plugged into the Internet right now, chances are extremely good that your data is traveling through an Ethernet cable along some point of its journey. Ethernet, the thought child of Robert Metcalfe, will have been around 37 years as of this Saturday, May 22nd.
Ethernet has enjoyed nearly two decades of supremacy as the de facto way to connect computers together in a home or office. It wasn’t until the recent widespread adoption of wireless technologies that the Ethernet cable started becoming an afterthought in people’s laptop bags and backpacks.
I’m curious as to how many of us in the studio could actually produce an Ethernet cable from their laptop bags right now… Anyone?
Most people are wireless these days, and since Kaveh Kanes closed, I know of no coffee shop in Houston where I can show up with a 20 foot Ethernet cable and expect to get connectivity. Of the two, Wireless is actually the more venerable technology, though, with Ethernet borrowing some of its tricks from one of the very first wireless networks that was created to connect several University of Hawaii computers together in 1970.
This network, the aptly named Alohanet, used amateur radio to link nodes together. Using one frequency to transmit and another to receive, a machine receiving data would immediately re-transmit that data back the origin machine, thus introducing the ability to detect and correct errors during transmission. Aloha also tackled the issue of collision detection, a condition when two computers try to talk at the same time, by just dropping both transmissions and simply trying again. Transfer speeds on Alohanet maxed out the Data Terminal Equipments built-in baud rate of 80 words per minute. That’s Teletype speed for you old timers…
Another networking technology was coming on very strong in the 70s that may have displaced Ethernet if not for one single flaw. IBM’s token ring technology overcame the problem of collisions by using a 3-byte token that was virtually passed between computers connected in a ring pattern. Only the computer in possession of the token was allowed to talk, or transmit data, while all other remained quiet. This ruled out the possibility of data collision. Token Ring speeds kept up with Ethernet speeds, with IBMs 16 MB/s Token Ring technology being introduced in 1989, eventually becoming the IEEE standard for token ring networks. Both Apollo Computer and Proteon offered other proprietary token schemes in the 80s. And though IBM did beat out those companies, it was Token Ring’s large plastic connectors and thick IBM Type 1 cabling that kept it from overtaking Ethernet. Token Ring speeds eventually hit 100MB/s, but would never see the multi-Gigabit Ethernet speeds realized today.
Early Ethernet cabling looked a lot like the coaxial cable that used to bring cable television into homes before satellite hit the scene. Now, Ethernet cabling takes the form of 4 twisted pairs of wire sheathed in a plastic coating. The end connectors are known as RJ-45 connectors, a larger version of what you still find on the ends of phone cabling, which is known as RJ-11.
So happy 37, Ethernet!
That’s exactly the half-way-point of this season’s sizzle and that’s that for BarretTime.
