Ethernet Inventor Sees No Limits To The Technology

When Bob Metcalfe was working at Xerox Corp. in 1970, he was given the task of developing a way to network computers using a standard interface. He invented what's now known as Ethernet, the technology employed by just about every data network in use today.

"Way back when, Xerox scientists built their own tools," Metcalfe recalls. "We were about to put a computer on every desk and needed a way to interconnect them. I was fortunate to be the networking guy given the job."

Ethernet started out slow, but continues to gain speed. At first it ran at 2.94 Mbps, because the clock on the back plane of an Altos computer ran at that speed. Today, Ethernet can run at 10 Gbps, and Metcalfe sees no reason why it can't run at much faster speeds in the future. "The next stop will be 40 Gbps or 100 Gbps," Metcalfe says. "Phone companies like to increase their speeds by a factor of four for every new generation, while data folks like to increase speeds by a factor of 10. It's not clear who will win out."

Metcalfe notes that as more telecom companies offer Ethernet services, Ethernet is becoming a carrier standard and not just a LAN standard. "That means we may have to stop at 40 Gbps on the way to 100 Gbps," he says.

The widespread use of Ethernet is a key reason Metcalfe was awarded the National Medal of Technology by President Bush at a White House ceremony Monday. It wasn't something that he expected to result from his invention many years ago. "I am willing to admit that I had no idea that Ethernet would get as big as it has," he says. Last year, 200 million Ethernet ports were shipped.But Ethernet can grow even larger, Metcalfe says. He talks about the technology going in four directions: up, down, over, and across. "Up" means that Ethernet will get faster and faster. "Down" means reaching out to the many computers that aren't connected. "There are 8 billion microprocessors shipped every year, and 98% of them are not networked," he says. "Ethernet is going down to get them."

"Over" refers to wireless. "There will be more Ethernet running over Wi-Fi and WiMax wireless networks," he says. And "across" means serving as a bridge between LANs and WANs. "Ethernet will finally reach across the telechasm and fill the gap between local area networks and wide area networks," he says. "That gap is due mostly to the procrastination of the carrier monopoly. But the growth of carrier Ethernet services means that customers will buy Ethernet services instead of a T-1 Sonet line. Carrier Ethernet will mean the death of T-1 and Sonet, which are outmoded technologies. Businesses will be able to buy much cheaper bandwidth at much higher speeds."

While some businesses will still build private wide area networks, Metcalfe predicts that fewer will do so because "carriers' services will be much cheaper."

He also believes that Ethernet will help to bring about the video Internet. "Video is coming," he says. "The video Internet with video mail and video messaging and videoconferencing and video phones and video merchandizing. The public Internet will more and more be able to carry real-time video."

He calls the growth of video on the Internet the "obvious next move" and predicts that the kids who today "are stealing CDs over the Internet will soon be stealing full-length videos."0