nteractive services (which are very delay sensitive) directly to the user, more satellites are now being launched at the lower orbits. We are beginning to see data rates of up to 155Mbps with GEO systems, partic- ularly in the Ka-band. That data rate is not commonly available today, but it is fea- sible with the new generation of broadband satellites. Going to higher data rates, however, necessitates larger antennas, more SO for GEO systems than for satellites in other orbits. Parabolic satellite antennas 33 feet (10 m) in diameter can now be built, and it should soon be possible to extend them to 66 feet (20 m) or 100 feet (30 m). The main applications of GEO systems are one-way broadcast, VSAT systems, and point-to-multipoint links. There are no delay factors to worry about with one- way broadcasts from GEO systems. As a result, international television is largely distributed over these satellite networks today. VSATs Business enterprises use VSAT networks as a means of private network- ing, essentially setting up point-to-point links or connections between two locales. A VSAT station is so compact that it can be put outside a window in an office envi- ronment. VSATs are commonly deployed to reduce the costs associated with leased lines, and depending on how large the network is, they can reduce those costs by as much as 50%. Most users of VSATs are enterprises that have 100 or more nodes or locations (e.g., banks that have many branches, gas stations that have many locations, convenience stores). VSATs elegantly and economically help these types of enterprises do things such as transport information relevant to a sale made from a remote location to a central point, remotely process information, and process res- ervations and transactions. (See Figure 2.7.) Another use for VSATs is business video. Before about 1994, the only way to do point-to-multipoint video was by satellite. No terrestrial conference bridges would allow it. So, if you wanted to have a CEO provide a state-of-the-company address to all employe