When we talk of geostationary satellites, which are typically 36.000 kilometres above the surface of the earth, the advantages are that they have a very simple configuration, they can cover a very wide area, as a matter of fact, if we have three satellites at 120° to each other, the entire globe could be covered, and it has got minimum routing problems, in the coverage area and, since they are just synchronous, you have insignificant Doppler-effect.