When I am not studying to get better at my job or to pass a certification test (or being a husband and dad), I enjoy reading. A lot, actually. A majority of the books I end up reading are related to history; not just American History either. I love to read about inventors and explorers, about mythology and sociology. One of my favorite books of all time, ‘Cryptonomicon’ is like an ideal mix of things I love: History, spies, and technology, covered in a hard candy shell of weirdness. If you’ve not read it, I would highly recommend it.
Back to my point: I find it interesting to read about the people that invented a certain technology or protocol, especially the ones I rely on. I like reading about the inspired team that developed the ARPANet IMP (Internet Message Processor, the first router), and about Vint Cerf and Bob Kahn and Linus Torvalds. I think it’s really cool to hear or read firsthand what these folks had in mind when they invented Ethernet or Linux.
It’s interesting because I am floored by these creations, and could not imagine being a pioneer in the same manner that these folks are.
Networking is (and was) without a doubt a male-dominated area of expertise, but one woman in particular changed the face of networks indelibly and her name is inextricably linked to a technology that is near and dear to my heart: the Spanning Tree Algorithm. The computer genius responsible for loop-free layer 2 topologies is a woman named Radia Perlman. She is sometimes referred to as ‘The Mother of the Internet’. I guess if there is a Father of the Internet (or multiple Fathers), and a Father of the Web (Berners-Lee), then there has to be a Mother as well, right?
If so, it’s Dr. Perlman for sure.
I bring her up because in the course of my Internet readings today, I saw that Dr. Perlman is receiving the Association for Computing Machinery’s SIGCOMM Award for 2010, for her contributions to networking that ‘we all use and take for granted every day’. She is delivering the keynote speech at the event. If you happen to be in New Dehli at the end of this month, stop in…
Dr. Perlman has received a lot of these awards in the past, I am sure. She’s gotten multiple patents in areas of networking and network security. But I think that the ACM SIGCOMM announcement hits the nail on the head: her contributions to network bridging and routing are fundamental and lasting.
I first heard of Radia Perlman in the late-1990’s, when I was given a book to read by my mentor and boss at the time. This boss was a firm believer in learning the fundamentals of networking, and the book I was tasked with reading was actually a mandatory assignment. It was a performance review goal, so I had to do it. Making it mandatory made me gripe and complain a little, but once I started reading that book, I was very glad that I did.
The book in question? ‘Interconnection: Bridges and Routers’ (it has since been retitled to add ‘Switches’ in there after ‘Bridges’).
Dr. Perlman’s writing style is light and easy to read (especially when compared with some of the other textbook-style books on networking, like ANYTHING by Stallings. Yawn).
She starts out where pretty much every networking book does, with the OSI model, but the difference in ‘Interconnections’ is that she emphasizes that the OSI model is a framework and guideline, not a set of inflexible, carved-in-stone rules.
Since she is the inventor of STA, I always recommend reading her book as a primer for those that are studying vendor-specific implementations of STP. Reading straight from the source what she was thinking and what she was intending and why she made certain choices along the way in her original design is totally worthwhile. She even includes a corny poem about STA. The whole book is worth reading, and leaves little room for doubt about the breadth of the author's knowledge.
I continued researching today about Dr. Perlman, and found that there is a great article from the MIT Admissions Blog and Investor’s Business Daily from a few years ago about Perlman. She has a Bachelor’s and Master’s in Math and a Ph.D in Computer Science, all from MIT.
The article talks a bit about what kinds of struggles she faced as a woman in the early days of her career. People tended to ignore her contributions, in spite of the fact that she is a trained and educated mathematician; the article tells of an incident in which Perlman presents a solution to a routing issue, spending 30 minutes detailing her solution using an overhead projector, to be completely ignored by the meeting organizers. It is fortunate that she chose to continue on.
The article goes on to explain that Perlman took a job at DEC, and was given a task involving getting nodes on a network to communicate. Other engineers at DEC had been working on the problem for months, with little progress and success. Perlman provided a solution to the problem the next day. I am not 100% sure, since the article is short, but I believe it was the beginnings of STA that were the solution.
Dr. Perlman also mentions, in the article, that teaching others and writing are great ways to keep challenging oneself and learning. To quote,’You can never learn enough, she believes’. She is correct. She also says that one of the best ways to learn something that is really going to stick in your mind, is to teach it.
The next time you are getting ready to add a LAN switch to your network, or set up an etherchannel, or just about any other change, give a ‘Shout Out’ and say a 'Thank You' to Spanning Tree, and its creator, The Mother of the Internet, Dr. Perlman.
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Happy Birthday, Internet.
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Birth of the Internet is today! It turns 41
September 2, 2010 marks the 41st birthday of the network that would become the Internet. I know you are a big fan of the Internet and networks, just like I am, so it is fortuitous that the 41st anniversary of the first packetized data to cross the first router (Interface Message Processors, or IMPs) is in just a couple of days.
I know what you’re thinking: Is the first message on the first router really something that should be commemorated? I mean, we don’t celebrate the invention of, say, concrete (although there are a lot of sites on the Internet dedicated to the history of cement and concrete!).
The first communication between the IMP, and a computer (in this case called an SDS Sigma-7), happened in the Network Measurement Center at UCLA. The IMP was build by a company that still kind of exists called Bolt, Berenak and Newman (although, now it’s called BBN Technologies). BBN has long been involved in defense contracting work in the US, and was founded by a couple of MIT professors and a former student.
The first communication to take place between two IMPs with attached computers, happened on October 29, 1969, between UCLA and Stanford University.
The first birthday message?
‘Lo’.
‘Lo’, the first message sent between the IMPs at UCLA and Stanford, was the result of a system crash. According to sources, it was supposed to be the word ‘Login’, but the system crashed and it took an hour to bring the system back up.
It’s not really like the first message sent, ‘Lo’ is really on par with,’Mr.Watson—come here—I want to see you.’ Is it?
I personally think it’s a close second.
The telephone revolutionized communication in the 19th century. Before the telephone, you had to send letters or possibly a telegraph. Both had and still have disadvantages.
Letters took a long time to across the country or across oceans. A long, long time. Telegraphs required an expert at each end that could receive and transpose the message from code to words. Telegraphs tended to be expensive. Telegraphs, and Morse code, were technological game-changers in their own right, since communication could be almost instant. But it’s not the same a hearing a voice over a machine and network spanning miles and miles.
The telephone, as early as the 1890s, made it possible to speak to other people over long distances. Witchcraft!
Back to the Birth of the Internet:
In the ensuing 41 years, this nascent ARPANET, which had four ‘nodes’ by the end of 1969, has changed everything.
At roughly the same time, throughout the 1970s and ‘80s, computers themselves went from being monolithic entities at research institutions for crunching numbers to being a hobby, a vocation and even a profession for so many people. PCs and Macs made computers accessible to anyone with a little money and some time to learn. People, even at the start of the home computing era, realized that being connected to others over a network is way more fun than being on your computer all by yourself.
Even before graphics and free dirty pictures.
People wanted, and still want, to be able to communicate and share information in real time.
Myth-busting Time!
One thing that I have heard countless times is that the Internet was started to address a certain defense-related problem: In case of a missile strike on the US, there needed to be a decentralized network so that we could, essentially, fire back. A centralized control facility would be the enemy’s main target. We needed to be able to strike back even if one facility was destroyed.
Guess what?
Not so.
The book I am reading on this at the moment, ‘On the Way to the Web’, says this was not really the case at all. People ended up confusing the ARPANET with a project being worked on by the Rand Corporation at the time. The Rand Corporation project was a voice network project, wherein the network could survive and function if some of the links were taken out. It did involve packetizing messages, so maybe it was an early form of Voice-over-X technology (since IP was not yet completed). I started thinking about this more, and it makes sense: at that time, missile sites were manned by men, not machines, so a resilient voice connection was more important than a primitive form of Email. The men in the silos would want to speak to one another. (See ‘Wargames’ if you have not already).
The lesson learned from this little tidbit? Not everything the ARPA (now DARPA) did was related to making war.
But this ode to the Birth of the Internet is not just about appreciating the Internet. The Internet made all the protocols we use on a daily basis necessary, which in turn gave many of us opportunities.
Remember that from its humble beginnings, the Internet has remained a place for learning and information sharing.
So, today on the birth of the internet, when you click over to this post, or to any other of nearly countless web pages, remember to marvel at the Internet and what it has done for so many of us.