On Sept. 11, the first thing I did after staring at a jetliner taking out the second tower of the World Trade Center on CNN was pray. The second thing I did was to try to reach my friends and family who live in lower Manhattan: Me and about a million other people.
The phone system could no more handle the load than I could run to New York City from my home in the Blue Ridge mountains. So what did I do? I turned to the Internet, of course. And that's when I heard on CNN that the Pentagon, near Washington, D.C., had just been hit-the area in which I had lived for the last 15 years.
You want to hear a voice first; I tried to call into D.C., though I knew it was futile. Hope over knowledge and knowledge won-the lines were already jammed up. Once more, I kicked on my DirecPC satellite uplink to the Internet and I was on the Internet in a minute.
Five minutes later, I was sending e-mails off my address list as fast as I could type, and the AP news service wire was scrolling in one window while The Washington Post was getting updates every 15 minutes in another.
Information was coming in fast but not fast enough, and then it hit me: instant messaging. A minute later I had my Linux Java-based AOL Instant Messenger (AIM) client up. The first person I managed to reach was my long time friend Mary Jo Foley. Inside of five minutes I knew that most of my friends and family were OK. By day's end, I knew all of them, including the one who lived six blocks from the World Trade Center, were safe and sound. If it weren't for the Internet, I still wouldn't have known more than 24 hours later.
The Internet had done what it had originally been designed to do: survive a disaster of epic proportions. Then, ARPAnet had been meant to shrug off a Soviet nuclear attack; on Sept. 11, it survived not only having one of its many strongholds, the switches and routers beneath the World Trade Center, destroyed, but also what may have been the most activity on the Net ever.
My personal experience was upheld by Matrix.Net, one of the leading and certainly the most experienced Internet performance measurement companies around [This site is no longer available]. John Quarterman, Matrix's CTO, reports that Internet sites, which are normally at 96 percent reachabilty, dropped to 86 percent reachability that morning. Since then it has almost recovered and is hovering around 94 percent. Latency times, the time it takes to get a response from a site to your PC, also reached a low of three seconds in some areas. Slow, yes, but far better than, say, a Manhattan business phone that probably had a reachability of 2 percent that terrible morning.
Mail servers, on the other hand, took a hit. While the bulk of e-mail is getting through, several ISPs, such as AOL and Canadian e-mail provider ApexMail, appear to have been overwhelmed by the mail load and had significant mail delays.
Instant messaging, however, had its finest hour ever. Using AIM, which AOL reports had its most use ever with 1.2 billion messages sent, I was able to instantly communicate from the Appalachian woods with people in midtown Manhattan and next door to the Pentagon. I wasn't alone; hundreds of thousands of others were doing the same.
There are several lessons to be drawn from this day. The first is that the Internet really is robust. Despite the Code Reds, despite a massive usage surge, the Net is as sturdy as its planners ever could have dreamed. If anyone still has any doubts that developing for TCP/IP and the Internet is the only way to go, those doubts should be erased now.
The next is that the reason why so many Web servers stayed up and running was that the redundancy in both Net connections and in servers finally paid off. When the demand grew, the most important sites were able to bring more servers and bandwidth into play to meet the demand.
It still wasn't enough, of course. Some sites slowed to a crawl, but to the best of my knowledge, no news site buckled under the demand. Under the massive load, though, e-mail simply didn't work as well as the Web and instant messaging servers.
So, yes the Internet stood up amazing well, but this was also a call to arms. Our predecessors built a system that could take a hammer blow and keep running. As we enter a time of war-and make no mistake about it, we are-we need to build programs that are cracker-proof. We need to create software that can handle loads beyond anything we used to think were reasonable loads. Now, more than ever, it's time to build the best possible software we can because there's no telling when a sometimes trivial program-instant messaging-could become vital.