Mockapetris on the Domain Name System

Paul Mockapetris is the computer scientist who invented the Domain Name System (DNS) and is one of the founding fathers of the Internet. After leaving the university world in 1995 he served as engineering director of cable modem-based high-speed Internet access provider @Home. He now is at DNS and DHCP software solutions provider Nominum Inc. Paula Bernier, Editor in Chief of xchange, recently spoke with Mockapetris about DNS.

XC: You invented DNS. Can you offer some insight on what sparked the invention?

PM: The original reason for the invention was people felt that as the ’net grew — they were thinking in terms something like 200 to 1,000 computers — they didn’t want one place keeping track of the configuration. And the configuration then was just the mapping between host names and addresses.

Today, we have about a billion computers that use the DNS, and there’s dozens of applications that have been defined — mail routing being the best known. And it’s not just computers; the 3 billion or so phones out there are getting their own entries in the DNS.

So the DNS has grown from being just the host name registry into the most widely distributed database on the planet — one that’s used in a lot of surprising ways. For example, most of the worldwide DNS data is private and not in the public Internet. And while we hope for a single public name space, there are a lot of private DNS applications that are totally disconnected and distinct from the public space.

XC: I understand you also helped design the SMTP protocol for e-mail. I’ve been reading lately that e-mail now is considered snail mail — at least by some young people who prefer IM. How do you see e-mail and messaging evolving in the next 10 years as a result of that trend? Will e-mail become outmoded?

PM: Sooner or later, IM and e-mail will converge. When I attach a file to IM or e-mail and it takes a while to get to the destination, I’m not sure there’s much of a difference. It’s amusing to note that the original SMTP specs had IM as a component, but nobody bothered to implement it.

All these ideas are related. In the future, maybe we will all have IM, but it will get universal addresses like Internet mail has today. When you see an Internet e-mail address on a business card, you expect you can send e-mail to it. That’s not the case with IM. Sooner or later the natural selection will kick in. I think some DNA from IM and some DNA from the e-mail world will combine.

XC: What were you doing professionally 10 years ago?

PM: I was at @Home. I was director of network engineering, deploying the first Internet-over-cable systems in Sunnyvale, Calif. That gave me a lot of satisfaction. Today, everybody accepts cable as a medium.

XC: From your perspective, what have been the biggest changes in the industry in the last 10 years?

PM: A recognition by incumbents that Internet technology is the wave of the future, and the fact that they’re moving to that kind of a model.

People from the Internet world say the Internet changes everything. That may be true, but the real world pushes back on the Internet — spyware, advertising, ringtones, etc. It goes both ways.

There’s also the change in the Internet population — starting with network researchers, moving on to the educational world, then business users, and now the general public, with every device that has a silicon chip soon to follow.

XC: How, if at all, did the Telecommunications Act of 1996 contribute to those changes?

PM: It provided a lot of funding that perhaps didn’t really go where people intended, but then again it never does. It allowed a lot of experimentation.

XC: What led you to where you are now professionally?

PM: A VC asked me to come by and look at Nominum and do due diligence. And one thing led to another. I had been out of the DNS world for a decade, so it was back to the future.

XC: What do you think the Internet will look like in 10 years?

PM: There’s now fewer Internet connections than there are telephones. In a few years, there will be more. The big growth, after we figure out how to take care of every man, will be devices. My car will send me reports on its health via wireless.

Distance will continue to disappear. So I’ll be able to access my home network no matter where I am.

I think my favorite slogan is that the future of the Internet is ahead of it. I think the communications stuff will mostly disappear in the background — [in the future] you won’t configure your network; [it will configure itself]. That is the big technical challenge.

To read an expanded version of this interview, visit xchange's Added Insight section at www.xchangemag.com/addedinsight.

Share this article: Email, Slashdot, Digg, Del.icio.us, Yahoo!MyWeb, Windows Live Favorites, Furl
Add this article feed to: RSS, My Yahoo, Newsgator, Bloglines