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Despite today's scarcity, many experts are still optimistic about future launches. Pioneer's Clavenna says even though capacity must double over the next five to eight years, launch services can be lucrative, so there is great incentive for the investment to be made. He believes the shortage will primarily affect the fortunes of smaller companies that can't afford to reserve facilities and vehicles. Steven Goldstein, National Science Foundation program director for international networking coordination, also says that the push to get satellites in orbit could result in the mass production of la unch vehicles. "There's no reason we can't bang them out on an assembly line--that's what is needed to reduce costs and increase reliability," he says.

The Application Advantage
Once spaceborne, satellites will be called upon to perform a variety of tasks. Most satellite providers are expected to make a big play for customers based on QoS (quality of service). It's an important emphasis, given that businesses choose providers for their service attributes--QoS, cost, reliability and availability--rather than the type of technology they deploy. QoS is seen as crucial, in every sense of the word. Most satellite providers plan to offer uptime guarantees and some even have plans for hybrid systems that will sort traffic for LEO, GEO, MEO or terrestrial transmission (see "GEO-LEO Hybrids: Two Mints in One," on page 82).

GEOs are apt to prove best for broadcast, multicast and latency-insensitive applications, while LEOs are more apt to be used for interactive applications like voice and videoconferencing. BBN principal scientist Craig Partridge suggests that GEOs cannot be brought within the performance range of LEOs without TCP spoofing or pursuing alternatives that aren't yet off the drawing board. On the other hand, IETF chairman Fred Baker says LEO routing isn't exactly a done deal and questions persist about the effect of jitter on LEO transmissions.

One of the most significant broadband satellite markets will be providing a high-speed mechanism to take the 75 percent of Internet content now in the United States and move it to ISP caches around the globe. The fact that satellites can be tailored to provide asymmetric bandwidth is particularly valuable for this type of provisioning.

Similarly, next-generation satellites will probably be strongly driven by their ability to link remote offices and telecommuters to central offices, and to provide a means for centralized offices to broadcast information to remote sites. Gartner Group's Egan says he believes the biggest corporate use for satellites will be information distribution--database updates, audio/video broadcasts and remote access. In developing nations where mountainous terrain or lack of infrastructure prevent access, satellites will provide a ready-made last-mile infrastructure. There is also widespread agreement that GEO satellites are superior to any type of terrestrial transport when it comes to IP multicast. This is primarily because they remedy the congestion otherwise seen in point-to-point services.

Clavenna says satellites' ability to interconnect disparate voice, data and video networks will prove valuable. He expects, for example, to see some hybrid LEO-GEO systems, like those from Motorola and perhaps Loral, bring satellite phone services into their packages. New broadband systems, he adds, will give businesses and individuals the flexibility to quickly relocate within a system's coverage areas.

Backup is yet another suitable application for next-generation satellites. Passmore, however, warns th at businesses either will have to pay a premium to guarantee that backup or find themselves joined by 100 other companies trying to access satellite constellations following a major disaster like a hurricane or earthquake.

Finally, analysts say it won't just be large businesses relying on next-generation satellites. They also expect adventurous small and midsized businesses to use these services.