National Internet service provider Netcom has completed a six-month upgrade of its network backbone that should let data traffic flow faster and help the company keep up with the ever-increasing demand for bandwidth.
The backbone is the part of the network that connects the network's main hubs, the departure points through which all online traffic is routed on its way from the PC to servers everywhere. Upgrading the backbone doesn't mean that users will be able to detect appreciably faster speeds to their local servers because data always travels along the lines at the same rate; where data slows down is in passing through these hub waystations, and the upgrade effectively opens the pipes so that data doesn't back up at these key junctions.
Faster backbones mean fewer and less noticeable Internet traffic jams when data clogs up like airplanes backed up along a runway.
The backbones share traffic from many access providers, and data can travel from one backbone to another in the course of delivery. But most ISPs are upgrading their backbones in an effort to speed whatever portion of the information superhighway they're responsible for.
Because it is one of the nation's biggest ISPs with 479,000 subscribers, Netcom's upgrade is one of the most ambitious projects of its kind. The upgrade was designed to account both for a 300 percent growth of its customer base in 1995 and for future growth by providing a more flexible kind of technology that can be upgraded again, only faster next time.
The company's backbone hubs are now connected by ATM (aynchronous transfer mode) switches, a kind of technology that transmits data at a basic rate of 45 mbps, compared to 1.45 mpbs and 45 mbps for the T1 and T3 connections it replaces.
The new backbone not only uses faster technology, but a more efficient architecture. The old backbone configuration was a ring that connected such cities as Chicago, San Jose, Los Angeles, and Dallas. Data had to travel from the sender to the nearest hub and then around the ring.
The new system is a "meshed" network more akin to a highway system where data travels along the shortest and most logical path. With fewer transfer points, the company says the data will travel as much as 50 percent fewer physical miles and hopefully arrive at the other end faster.
ATM infrastructure can also be expanded faster to higher speeds than some other backbone technologies, such as frame relay.
Still, Netcom officials can't promise a noticeable difference in the speed of, say, an email from sender to receiver. "It's hard to say because there are so many elements involved," said Netcom vice president of operations Bob Tomasi. "You really can't set expectations based solely on the backbone. It's not the answer; it's part of the answer."
One of Netcom's main competitors, PSINet, is also responding to demand for greater bandwidth. The Virginia-based ISP announced today that it received 149 customer requests for bandwidth upgrades in the second quarter of 1996, compared to 59 in the second quarter of 1995.
PSINet's subscriber base has grown in the same period from 34,200 to more than 130,000, almost three-quarters of whom are home users.