This summer’s railroad tunnel fire in Baltimore posed much more than a commuting nightmare; it had plenty of Web users choking, too. That’s because WorldCom’s (www.worldcom.com) UUNet Internet service lost a segment of its network, which affected not only its own customer base but also the users of other Internet service providers. Like many other ISPs, UUNet relies on “peering relationships,” or agreements with other ISPs to carry one another’s Internet traffic. Such arrangements save ISPs vast sums of money, but they also pose a risk for customers, and some industry-watchers believe it’s only going to get worse.
Having overinvested and overleveraged to keep up with the explosive growth of the Internet, ISPs are now left with debt and with a customer base that’s growing little, if at all. That financial instability can be as damaging to peering networks as the Baltimore fire. Take PSINet. In June, right after the company announced it had filed for bankruptcy under Chapter 11, Cable & Wireless (www.cw.com) severed its peering connection with PSINet on the grounds that there wasn’t enough reciprocal traffic between the two. Normally, if a peering relationship is lopsided, the party with the additional traffic pays for the carriage of data. Since PSINet had no money to spend, Cable & Wireless pulled the plug.
To avoid being the unwitting victim of a peer dispute or interruption, make sure your ISP has connections to multiple backbones. According to Bill Jones, senior director of public services at Keynote Systems, a company that monitors Internet performance, “When you contract for support of a vital part of your business, you have to make sure there are plans for responding to a critical path failing.” Not surprisingly, he says that “typically, it comes down to how much you’re willing to spend” versus what you’re willing to risk.