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Why only one satellite?

When Galaxy IV lost its way, millions lost communications--leaving some wondering why so many services depend on one satellite.

When close to 90 percent of all U.S. pagers stopped beeping and vibrating this week, consumers from teens to doctors may have wondered for the first time how the little box they so depend upon actually works and what made it suddenly stop.

Because of a computer failure, PanAmSat's Galaxy IV satellite lost its way Tuesday night, sparking a nationwide crisis management frenzy to redirect paging services to backup satellites. Wireless Internet access, some television audio feeds and news service transmissions also were disrupted.

Some users expressed surprise that the paging industry was so dependent on a single satellite. But satellite communication experts said today that there are a few simple explanations for why only one of PanAmSat's 17 global satellites was servicing almost all of the country's 40 million to 45 million pagers.

For starters, since 1993 Galaxy IV has been stationed in prime space "real estate." At 99 degrees west longitude, Galaxy IV is able to cover the entire lower 48 states with almost no interference from mountains, buildings, or even the horizon.

"That position has been popular since the late 1970s. It is a primo orbital position that is kind of right dead-center in the country," said Mark McKibben, head of the Society of Satellite Professionals' Southern California chapter and president of McKibben Communications.

"Over the years, as wireless networks grew, the replacement satellites that went into the 99 slot 'grandfathered' the services that were already going there," he added. "It's easier to consolidate traffic on one satellite than to repoint thousands of [antennas]."

Also, Galaxy IV was able to link up so many pagers because satellites can generally handle massive capacities, and the signals take up relatively little bandwidth compared to such transmissions as television.

The company's marketing didn't hurt either. PanAmSat pitched Galaxy IV as the ultimate satellite for paging services.

"That was how the satellite was marketed--as a telecommunication satellite," said Marc Kuykendall corporate communications director for SkyTel. "One reason we were able to respond quickly with most of our customers is that we didn't have 100 percent of our traffic on Galaxy IV."

Although SkyTel's 1 million traditional pager customers were only momentarily affected by the outage, about 300,000 two-way pager clients were out for some time, Kuykendall said. The bulk of its service was immediately redirected, but SkyTel did not have a backup system fully in place for its range of next-generation, two-way paging services, which allow people to respond to messages using the pager instead of a telephone. For example, some of the handheld devices contain a menu of responses, while others are more interactive--letting users devise customized messages with a tiny keyboard.

PanAmSat said paging services were a small percentage of the total bandwidth on the satellite, but that Galaxy IV was primarily pitched to that market.

"Galaxy IV is simply in a prime orbital location to cover all the United States. For pages that want to cover all the area they can, that was the satellite to be on," said Rebecca Petruck, a PanAmSat spokeswoman.

Considering the industry has never faced an outage of this scale, Kuykendall said, its response has been excellent. Companies had to send technicians out all over the country to redirect antennas. And by noon today, most of PamAmSat's service was transferred to another satellite. In about six days, the company said a satellite located at 74 degrees west longitude would be moved to Galaxy IV's old spot.

Still, as of late yesterday, only 40 percent of PageNet's 10.4 million pagers in the United States and Canada had their service restored, although the company expects most of the service to be reinstated by tomorrow morning. Service in less populated areas may not be restored until Friday.

"The industry has been working together to find replacement satellites and even going out and repointing each other's satellites," Kuykendall noted. "I think it will be safe to say that everybody takes this as a learning experience."

One lesson the industry learned is that more backup is need, experts said. The television industry, for example, is known to spread out its wireless connections and have alternate positions on deck if a satellite is knocked out.

"Today it happened to affect paging services, but if it was a different satellite it could have had an effect on cable TV and a whole host of different services we've come to rely on every day," said Paul Judge, director of management consulting for the Walter Group, a Seattle-based firm specializing in emerging communications technologies.

"The industry recognizes that these are critical communications and generally build in the ability to back up systems when they go down," he added.

For example, he said companies could buy antennas that focus on more than one satellite or those that can mechanically move when losing a satellite. Also, wireless services can make sure to have alternate satellites always waiting in the wings.

Federal Communications Commission Chairman William Kennard said in a statement that during the past decade the average failure rate of satellites has been about 1 percent. However, he plans to seek advice to curb future wireless service outages.

"After the problems are resolved, it is my intention to have our advisory committee in this area, the National Reliability and Interoperability Council, assess the cause of the problems and make appropriate recommendations to the Commission and to the telecommunications industry," he stated.

In the end, however, some disasters can't be avoided, said McKibben of the Society of Satellite Professionals.

"There have been a lot of satellites lost over time," he said. "There is no way to avoid a loss of a satellite--it's what they call an 'act of God.'"