Radia Perlman: Don't Call Me the Mother of the Internet

The woman who developed the algorithm behind the Spanning Tree Protocol reflects on her illustrious career in math, computer science, and networking.

When Radia Perlman attended MIT in the late '60s and '70s, she was one of just a few dozen women (about 50) out of a class of 1,000. There were so few other women around, she told me, that she often didn't even notice the gender imbalance—it became normal to her to never see another woman. It wasn't until she had class with another female, "that I’d notice that it kind of looked weird…this other gender person looking curiously out of place in the crowd. I’d have to remind myself that I was also that 'other gender.' "

Following her years at MIT, Perlman went on to become a leader in the field of computer science, developing the algorithm behind the Spanning Tree Protocol (STP), an innovation that made today's Internet possible. Today she is a fellow at Intel.

I recently corresponded with Perlman to learn more about her career, what it was like being a woman in the early days of computer science, and why she disapproves of a title sometimes given to her, The Mother of the Internet.

Tell me about growing up. Were you always interested in science and technology?

Both my parents were engineers working for the U.S. government. My father worked on radar; my mother was a computer programmer. Her title was “mathematician.”

As for me, growing up near Asbury Park, NJ, I always liked logic puzzles and I found math and science classes in school effortless and fascinating. However, I did not fit the stereotype of the “engineer.” I never took things apart or built a computer out of spare parts.

I was also interested in artsy things. I loved classical music and played piano and French horn. I also loved writing, composing music, and art. When there were group projects at school, other students probably had mixed feelings about being in my group. On the plus side, we’d almost certainly get an A. On the minus side, I’d wind up making the project into much more work than the teacher was really requiring. So, for instance, one time our group was supposed to do a book report on something and I turned it into a musical puppet show, composing the music, and having the group make the puppets and scenery and perform it for the class.

But speaking of grades, for some reason I really cared about getting all As. This definitely wasn’t because of pressure from my parents. I wish I could go back in time and tell my younger self not to worry so much. Or if I’d gotten a B at some point I wouldn’t have worried so much about my “perfect record”. But because of this obsession with A’s, most of my studying consisted of doing what I hated and was really bad at…memorizing meaningless (to me) dates and names for history class. I’d extract all the “facts” from the reading that might be on the test, memorize them, with my mother quizzing me on them to make sure I knew them all. Then I’d do well on the test, and 10 minutes after the test my brain wisely “cleaned house” and all memory of any of it was gone. Then something might come up on the news and my mother would say “Oh, you were just studying that,” and I’d look at her blankly, because it was completely cleared from my memory.

Although I love writing, my obsession with grades made me more drawn into science and math, because I could control what grade I got just by knowing the right answer. English made me nervous because of the subjective grading.

How did you first get into computer programming? What were the attitudes of friends and family?

Although my mother was a programmer, I didn’t really talk to her about programming. Mostly I remember talking to her about literature and music, although she did help me with my math homework in high school. A teacher commented that when the class was going over the homework problems, the other kids would say “my father said it should be done this way.” I’d say “My mother said it should be done this way.”

My first introduction to computer programming was that somehow a high school teacher managed to get several students (including me) to take a class in programming at a local university, Stevens Institute of Technology. She drove us to the classes. Aren’t teachers awesome!

Anyway, before this class, I was always confident that I’d be the top student in any science or math class. A weird observation though… I wasn’t actually happy about this. I had a fantasy that some boy would beat me at some math or science thing and my plan was to fall in love with him and marry him.

However, back to the computer programming class. I walked into the class, and all the other students were talking about how they had built ham radios when they were seven. I didn’t even know what a ham radio was. They were also asking questions using scary words like “input.” I had no idea what that meant, and it felt like I was so far behind that I’d never catch up. I wound up not getting anything out of that class. This makes me a good teacher though, because I understand the sense of panic and insecurity that can prevent someone from learning.

The way I actually learned how to program was that as a sophomore at MIT I was taking a physics class and the TA said to me “I need a programmer for a project. Would you like to be my programmer?” I said “I don’t know how to program.” He said “Yes, I know. That’s why I’m asking you. You’re obviously bright, so I’m sure you can learn (I was doing very well in the class), and I have no money to pay you. If you knew how to program I’d have to pay you.” At that time, I had a boyfriend who knew how to program. So even though learning programming seemed scary to me, it would be a safe way to learn.

My first paying computer job was in 1971 as a part time programmer at the MIT AI lab, in the Logo group, writing system software like debuggers. I worked there while going to school.

Then I got inspired to design a programming language, together with special “keyboards” and other input devices, for teaching programming concepts similar to Logo, but to much younger children. This was actually a cool project…and decades later some people from the MIT Media project tracked me down and said this project started a whole field known as “tangible computing.” But at the time, I abandoned it because, being the only woman around, I wanted to be taken seriously as a “scientist” and was a little embarrassed that my project involved cute little kids.

In your studies and when you first started working in the field, did you have many female colleagues? What was the environment for a young woman like in those days?

I went to MIT at a time when the number of females was strictly limited by the number that could fit into the single female dorm, so there were very few women (I think 50 out of a class of 1000). But since I was required to live in the women’s dorm I at least knew some women. But when I was a sophomore most of the men’s dorms became “coed,” and that sounded like fun, so I moved out of the women’s dorm and into a “coed” dorm. But with so few women, “coed” pretty much meant I was the “resident female.” I didn’t really see other women in the dorm. And I majored in math, so I didn’t see them in my classes either. It became so normal to me not to see women around that I didn’t notice the gender imbalance. It was only when occasionally there was a(nother) female in a class that I’d notice that it kind of looked weird…this other gender person looking curiously out of place in the crowd. I’d have to remind myself that I was also that “other gender.”

After graduating, I went to grad school, again at MIT in math. After I’d completed all my coursework and exams, I had no idea how to write a thesis. I had no advisor … MIT math department, at least at that time, was not helpful about matching students with advisors… An old friend asked me if I was enjoying grad school and I said “Not really. I have no idea how to find an advisor and write a thesis.” He said “Come join our group at BBN Technologies (Bolt Beranek and Newman)”, and so I did. That involved designing network protocols, and I really enjoyed it. I did wind up returning to grad school 10 years later, again at MIT, but this time in computer science, and completed my Ph.D.

Anyway, at BBN one of my coworkers there was female, and I really enjoyed working with her. But for a lot of my career since then, it’s been rare for me to be working on something in a group that has women.

After BBN, in 1980, I joined Digital Equipment Corporation, to design routing for DECnet, which happened to be the perfect job in the perfect place at the perfect time, but I really didn’t get to work with women there.

In what ways would you say that attitudes toward women have changed during your years in the field?

Honestly, not much has changed. Obviously it was possible to have a job in the industry long ago (like my mother did in the 1950s). People’s assumptions these days are that companies are desperate to hire and promote women, and that being female must be a big advantage. Companies do spend money on sponsoring events for women’s groups, but actual hiring decisions are based on subjective feelings, and I think there is often an unconscious bias where the hiring manager doesn’t really see a “true engineer” if the candidate doesn’t fulfill some preconceived vision (for instance, a younger version of himself). None of this is intentional, and it’s very difficult to do anything about it.

That being said, nothing is specifically gender related, even though some things might be statistically true. I’d suspect that a higher percentage of boys than girls dive right in and take things apart when they are young. But certainly not all boys do, and certainly some girls do. And, that’s not the only type of person that makes a good engineer.

The kind of diversity that I think really matters isn’t skin shade and body shape, but different ways of thinking. Yes, it’s great to have some of the people that desperately want to start writing code once they hear about a few special cases. But it’s also good to have other types of people, like me, that like to think about the problem a lot, from lots of different angles, and then realize the right problem to solve and the simple, general-purpose solution that will handle all the cases.

So it’s a real problem if a hiring manager has one specific notion of what an “engineer” should be like.

Another gender stereotype is that women are not as good about the kind of relentless self-promotion and politicking with powerful people that leads to rising through the ranks. It could be that a higher percentage of men are like that, and a higher percentage of women are self-deprecating, but I certainly know many men whose careers suffer because they are too humble, and I know some women that are as self-promoting as any man I’ve ever known.

Are there any specific instances or situations that you experience today that stand out to you as particularly significant or telling regarding women in technology? Any comments made by bosses or colleagues?

Again, pretty much nothing is purely gender-related. Though one woman told me she has a problem because her group likes to do team-building extreme sports together. They are all huge burly men. She, the only woman, is tiny, even for a woman. She can’t really play these sorts of sports with them. When she attempts to participate, like in ultimate Frisbee, they don’t throw to her (they don’t want her to get hurt). She feels left out. She suggested to her manager that the group do other things, like perhaps a pot-luck cooking party, but her manager sadly pointed out that nobody else in the group would want to do that.

One thing that I hate is when women “pick the wrong battles,” for instance, complaining if people use what women perceive as non-gender-neutral terms, e.g., in an email saying “Hey guys! That design has the following technical problem…” I cringe when some woman on the mailing list says “We are not all guys!”

That being said, of course there are genuinely hostile work environments with cases of genuine sexual harassment, and those have to be dealt with. But I think women would be much better off if we let the superficial stuff slide.

I had a manager once who was wonderful in almost all ways…really smart, really well-meaning, but I always made him nervous. He admired the tall pompous guys in the group, but he never quite knew what to make of me. When I did something really clever, he was smart enough to understand its importance, but then he’d look at me all confused and say “How did *you* think of that?” He meant well…

If you could, what advice would you give to your younger self? What do you wish you had known? What do you think you did right?

“What I did right” was pretty much due to a bunch of accidents. I just happened to get exactly the right job at the right time in the right place, so it was my job to design routing protocols at a time when the field was in its infancy. It was because of the way I approach problems, thinking it through conceptually rather than diving right in and solving each special case, that the designs wound up being so successful.

But I was not good about making a big deal out of what I did. My designs were so deceptively simple that it was easy for people to assume I just had easy problems, whereas others, who made super-complicated designs (that were technically unsound and never worked) and were able to talk about them in ways that nobody understood, were considered geniuses.

But what changed my life professionally was again a happy accident. I wrote the book Interconnections, all about layers 2 and 3 of computer networks. The field was really murky, full of jargon and hype. My book created order. It was easy to understand while being conceptually thought-provoking, and a large part of the technology described was stuff I’d invented. That changed people’s perception of me. I didn’t have to act condescending and scary when people learned the field from my book.

In terms of “What do you wish you had known”…I actually was the graduation speaker at the Rochester Institute of Technology once. The theme of my speech was “10 things I wish I’d known when I was your age.” I don’t remember them all, but here are a few that stick with me today:

• Life is unfair: it drives me crazy, because I want it to be fair, but obnoxious backstabbing people do well for themselves while really nice deserving people don’t do as well as they should, but this will never change, and you have to not let it bother you too much. The best thing you can do is try to help other people by mentioning their contributions whenever you get a chance.
• Everyone is insecure—especially pompous people. Really smart people are actually sweet and generous.
• It’s OK to ask for help. When doing a final exam, all the work must be yours, but in engineering, the point is to get the job done, and people are happy to help. Corollaries: You should be generous with credit, and you should be happy to help others

You've been called the Mother of the Internet, and you've also said that you do not like that title. What bothers you about it?

The Internet was not invented by any individual. There are lots of people who like to take credit for it, and it drives them crazy when anyone other than them seems to want credit, so it seems best to just stay out of their way. I did indeed make some fundamental contributions to the underlying infrastructure, but no single technology really caused the Internet to succeed. And sometimes, things get invented multiple times until the time just happens to be right. The thing that happened to be there at the right time isn’t necessarily better than the other ones.

But the Internet’s success isn’t due to the specific technologies, but rather the surprising ways in which it has come to be used. For instance, Internet search. It’s astonishing that Internet search is possible at all, but it works amazingly well, and is probably one of the most important reasons that the Internet is ubiquitous.