Bob Metcalfe, inventor of Ethernet

Bob Metcalfe


Bob Metcalfe's creation of Ethernet, a networking protocol that has become the standard in business LANs and as a service provider service, at Xerox PARC in 1973 in many ways is very much aligned with the emergence of the Internet.

Even though he was in the process of writing his Ph.D. thesis at Harvard, the Cambridge, Mass.-based university decided they did not want him to oversee its connection to the Advanced Research Projects Agency Network (ARPANET), the precursor to the Internet. Undeterred, Metcalfe secured a post at his alma mater MIT to work on their Project MAC system.

Showing that the second time can sometimes be the charm, Metcalfe, who was then working at Xerox's Palo Alto Research Center (XeroxPARC), found another subject for a revised dissertation in the University of Hawaii's ALOHAnet. In his revised thesis, which included analysis on how to improve ALOHAnet, he earned his Ph.D. from Harvard in 1973.  

Working in tandem with fellow XeroxPARC researcher David Boggs, Metcalfe first floated the Ethernet idea in May 22, 1972 in a memo titled "Alto Ethernet." In the "Alto Ethernet" memo, Metcalfe laid out a basic schematic of how Ethernet would work. However, Boggs reported that Nov. 11, 1973 was the actual day that Ethernet actually became a working system.

Like any emerging technology concept, Ethernet faced competition from two proprietary networking technologies--token ring and token bus--that were supported by IBM and General Motors. Despite this early competition, Ethernet prevailed over token ring and token bus because it could gain greater economies of scale by being able to migrate from coax to the traditional twisted pair copper already inherent in any business building.

After leaving XeroxPARC in 1979, Metcalfe made his Ethernet idea commercial with the founding of 3Com out of his apartment.

But Ethernet is not limited to the business LAN network alone. Over the years it has become a standard networking service offering delivered by traditional telcos like AT&T, Orange and Verizon, CLECs including MegaPath, PAETEC, and XO, and cable operators such as Cablevision, Comcast and Cox.

In 2011, Carrier Ethernet reached two major milestones. First the Metro Ethernet Forum (MEF), a group that provides standards for carrier Ethernet, celebrated its tenth anniversary. Second, a Vertical Systems Group report says that 2011 represents a "tipping point" in an uptick of new Ethernet service installations with bandwidth rates scaling up to 10 Gbps and beyond.

Following his ousting from 3Com in 1990, Metcalfe had a 10-year stint as a publisher and industry pundit. Since 2001, he has adapted his creativity around technology as a venture capitalist working as a general partner at Polaris Venture Partners.

Bob Metcalfe, inventor of Ethernet