案例库 · 软件与 IT · 战略决策 · 1973–1985
这条还没译成中文，下面是英文原文。
Ethernet won the LAN standard by being simple and by Xerox opening it to DEC and Intel.
A simple coaxial bus with collision detection ran on cheap wire, and Xerox opened it, so Ethernet beat Token Ring and Token Bus.
Xerox · DEC · Intel · 3Com
那一手
In 1973 Bob Metcalfe, working at Xerox PARC, wrote a memo proposing a way to connect the new Alto personal computers and the first laser printer over a shared coaxial cable. Dave Boggs turned it into a working network by November 1973.
The design was deliberately simple: every machine listened to the wire, sent only when it was quiet, and if two collided they backed off and retried. That carrier-sense with collision-detection rule made Ethernet cheap, fast enough to drive a laser printer, and easy to extend with more machines.
The decisive move was not the wiring but the openness. Metcalfe persuaded Xerox to join DEC and Intel to publish the DIX specification and make Ethernet an open standard. So instead of a Xerox-locked network, it became IEEE 802.3, and 3Com, Intel and a long list of vendors all built for it.
为什么管用
- A single shared coaxial bus with a simple collision rule was cheap and worked on ordinary wire, so it was affordable to deploy.
- It scaled as machines were added without reconfiguring the network, so growth did not require re-engineering.
- Xerox releasing the patents and publishing the specification let DEC, Intel and others build and improve it.
- Becoming IEEE 802.3 made it the default choice against IBM's token-passing Token Ring and GM's Token Bus.
可以搬走什么
A standard wins when it is simple and cheap to implement and the patent holder opens it - complexity and exclusivity will lose to 'good enough and universally adoptable'.
后来呢
Ethernet became the dominant local-area networking standard, evolving from 10Mbps thick coax to 10BASE-T twisted pair, Fast Ethernet, Gigabit and beyond. It supplanted Token Ring and Token Bus, and its frame format is the underlying plumbing of the modern internet.
资料来源
发现哪里写错了？告诉我们。