“以太网络(Ethernet)的发明是靠幕后一群无名工程师的协助；”Bob Metcalfe 一边深深吸了口香烟，一边回忆他在1973年5月22日写给Xerox PARC同事的备忘录中，所描述的一种现在已经无所不在的网络技术。
当烟雾缭绕在他的头顶，有些人名与故事逐渐从遥远的过去浮现；第一个人是史丹佛大学毕业的David Boggs，他是1973年时Metcalfe在PARC时的隔壁实验室同事。“Boggs在我笨拙地试图剥掉电缆末端的电线外皮以及焊接连接器时帮了我一把，那刚好是他很擅长的工作。”Metcalfe回忆。
以太网络的幕后推手之一David Boggs
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1976年，上面这两个男人与另一位同事Tat Lam，共同打造出后来变成以太网络的首个实验原型，是透过同轴电缆达到2.94 Mbit/second传输速率的一个连结。
3 Mbit/s 以太网络原型
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本文授权编译自EE Times，版权所有，谢绝转载
本文下一页：团队成员逐个回忆
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Lam是一位负责开发点阵式显示器的模拟工程师，与Metcalfe、Boggs同样在34号大楼的地下室工作，他帮忙为该原型开制作了收发器。后来Tam创立了一家销售以太网络收发器的公司，以他的姓名首字母命名为TCL。
Metcalfe吸了一口烟，又想起一个名字──Ron Crane，这是另一个史丹佛毕业生，Metcalfe雇用他加入Xerox 团队，后来创办那家将以太网络推向市场的3Com公司时，又邀请Crane过去担任硬件设计主管。
“Crane主导设计我们所有早期的以太网络产品，并与其它许多人共同协助发展IEEE标准；”Metcalfe回忆：“现在对以太网络有功的工程师名单开始越来越长了…”
David Boggs、Ron Crane与Robert Metcalfe
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本文授权编译自EE Times，版权所有，谢绝转载
本文下一页：“以太(Ether)”这个名字怎么来的
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的确，有无数工程师透过标准组织，协助推动不同种类的以太网络技术进入产品与市场；但这一切始于PC问世之前，PARC聘用Metcalfe开发一种能将该公司的Alto微电脑产品连成网络的方法，而当时他是取代先前一位工程师Charles Simonyi的位子。
“当我加入PARC，Simonyi转向负责开发一种文字编辑器软件，后来演变成微软(Microsoft)的 WORD应用程序，他也因此变成亿万富翁，还曾经上太空造访国际太空站两次。”Metcalfe又长长地吸了一口烟。
在 1973年写的备忘录中，Metcalfe列出对以太网络的想法，他构想出夏威夷大学Aloha网络的变形，并以其做为哈佛博士论文的一部分研究。 Metcalfe的研究成果有两大创新，一是以资料碰撞(data collisions)将干扰最小化的算法，其二是能在任何介质、甚至是神秘的“以太(Ether)”运作的灵活性，后来他也用“以太”来为该技术命 名。
1973年在PARC工作的Bob Metcalfe
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本文下一页：对于鼓励新人，我永不放弃
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以太网络技术在IEEE标准组织中，与包括IBM、甚至通用汽车(General Motors)等同样试图定义自家网络标准的大厂有多场战斗，在市场上也与其它网络技术斗争；最后，Metcalfe的概念成为局域网络(LAN)的基础。
Metcalfe 认为，以太网络的胜利有部分源于“我们所付出的诚意”，那与其它厂商提案动机是保护自家传统业务大不相同。而也许更重要的是：“以太网络了解自己在通讯层 中扮演的角色，只定义第一层与第二层协议，并没有想要做更多；也因为如此，它比其它竞争技术简单、成本也较低。”
以太网络最 终被采用为Wi-Fi以及一系列网络技术的基础，应用领域从工业控制、到在光通讯核心网络中取代Sonet，传输速率范围从3 Mbits/s 至 100 Gbits/s。根据市场研究机构 IDC的统计，在2011年，全球以太网络连结出货量为12亿埠，其中有8亿埠是无线通讯应用。
“现在的‘以太网络’与相同技术 CSMA/CD (Carrier sense multiple access with collision detection，载波侦测与多重存取)其实相去甚远，甚至已经不在其范围内；但这个名字被用来展现更大的想法。”Metcalfe表示：“它可能是封 包格式或者是符合官方标准、竞争激烈的商业模式，并具备向后兼容能力──我认为这是今日人们对以太网络的定义。”
Metcalfe 在去年接下一个新任务，担任美国德州大学奥斯汀分校的“创新教授(Professor of Innovation)”，他表示：“我的任务是让奥斯汀变成另一个更厉害的硅谷，计划的核心是一所工程学院，我在那里于协助工程师创业；如果你有兴趣开 公司，我会告诉你该怎么做。”
当被问到是否有任何他认为具未来潜力的无名新人工程师时，Metcalfe吸了最后一口烟，仅表示：“就算有很多人会泼他们冷水，我会为他们每一个人加油打气。”
本文授权编译自EE Times，版权所有，谢绝转载
编译：Judith Cheng
参考英文原文：Metcalfe on Ethernet’s lessons, unsung heros，by Rick Merritt
相关阅读：
• JDSU与北京邮电大学深化合作，加强网络工程师培育
• 重返乔布斯母校：谁启发了这些硅谷精英？
• 适合电子工程师的十大圣诞礼物kR0esmc
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Metcalfe on Ethernet’s lessons, unsung heros
Rick Merritt
“There’s an army of unsung engineers who helped invent Ethernet,” says Bob Metcalfe, taking a long drag on his cigarette as he ruminates about the now ubiquitous network technology he described in a memo to colleagues at Xerox PARC on May 22, 1973.
As the smoke curls around his head some of the names and the stories begin to emerge from the distant past. The first is David Boggs, a Stanford grad student who in 1973 was working in the next lab over from Metcalfe at PARC.
Click on image to enlarge.
David Boggs
“Boggs noticed I had trouble skinning and soldering connectors at end of cables and offered to help because it was something he was good at,” Metcalfe recalls.
By 1976 the two men along with another lab partner, Tat Lam, created the first prototype of what was to become Ethernet, a 2.94 Mbit/second link over a coaxial cable.
Click on image to enlarge.
Ethernet 3 Mbit/s prototype
Lam was an analog engineer working on a bit-mapped display in the same basement of Building 34 as Metcalfe and Boggs. He helped create the transceiver for the prototype. Later Tam created a company that sold Ethernet transceivers and bore his initials, TCL, before disappearing from Metcalfe’s sight like so much cigarette smoke.
Note: Bob Metcalfe says he does not smoke and never has. The interview was conducted via phone and the reporter mistakenly thought he heard sounds of smoking.
The Crane connection
Another drag, another name. Ron Crane, another Stanford grad student. Metcalfe hired Crane for his Xerox team and later recruited him as a hardware guru at 3Com, the company Metcalfe built to take Ethernet to the market. “Crane led the design of all our early Ethernet products and helped develop the IEEE standard” along with many others, Metcalfe recalled. “The list starts getting long now,” he said.
Click on image to enlarge.
David Boggs, Ron Crane and Robert Metcalfe
Indeed, hundreds of engineers have helped drive various flavors of Ethernet through standards bodies, into products and out to the market. It all began when PARC hired Metcalfe to find a way to network the Alto microcomputers it built in the days before the PC. He wound up unseating another engineer who previously had that charter, Charles Simonyi.
In a twist of fate, “when I came Simonyi switched to developing a text editor which over time evolved into Microsoft Word and made him a billionaire who has since visited the International Space Station twice,” said Metcalfe, taking another long draw on his cigarette.
In his 1973 memo, Metcalfe outlined his thoughts on Ethernet. He conceived a variation of the Aloha Network at the University of Hawaii he studied as part of a Harvard doctoral thesis. It sported two innovations — an algorithm that uses data collisions to minimize interference and the flexibility to run over any medium, even the mythical Ether for which he named it.
Click on image to enlarge.
Bob Metcalfe at PARC 1973
There were plenty of fights along the way in IEEE standards groups with giants like IBM and even General Motors who tried to define their own networks--and fights in the market trying to establish those technologies and others.
In the end, Metcalfe’s concepts became the basis for local area networks. Ethernet won in part “due to the sincerity of our efforts,” as opposed to the motivations of other proposals trying to protect legacy businesses, Metcalfe claims.
Perhaps more importantly, “Ethernet understands its role in the comms hierarchy, it was a Layer 1-2 protocol and didn’t try to do more than that,” he said. “As a result it is simpler and cheaper than the alternatives because it only did want it needed and not more,” he added.
Ultimately Ethernet was adopted as the basis for Wi-Fi and a wide range of nets that now span everything from industrial controls to optical telco core networks where it is replacing Sonet. It has evolved from 3 Mbits/s to 100 Gbits/s. Last year, vendors shipped 1.2 billion Ethernet connections, 800 million of them wireless ones, according to International Data Corp.
“It’s not even close to the same technology — CSMA/CD [Carrier sense multiple access with collision detection, one of Metcalfe’s early innovations] isn’t even in it anymore, but the name is used to embody a bigger idea,” Metcalfe said. “It could be the packet format or the business model of a de jure standard with fierce competition and backward compatibility -- that business model is I think what people mean by Ethernet, today,” he said.
Last year, Metcalfe took up a new job as Professor of Innovation at the University of Texas in Austin.
“My mission is to help make Austin a better Silicon Valley, and the core of that is an engineering school where I’m focused on helping engineers who want to start companies,” said Metcalfe. “If you are interested in starting a company, it’s my job to show you how to do it,” he said.
We asked if there are any unsung up-and-coming engineers he wanted to name.
“I am rooting for them all. There are plenty of people who will discourage them,” he said taking a last pull on his cigarette.
责编：Quentin
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