What is a VSAT?  

A very small aperture terminal (VSAT) is a device - known as an earth station - that is used to receive satellite transmissions. The "very small" component of the VSAT acronym refers to the size of the VSAT dish antenna -typically about 2 to 4 feet (0.55-1.2 m) in diameter- that is mounted on a roof on a wall, or placed on the ground. This antenna, along with the attached low-noise blocker or LNB (which receives satellite signals) and the transmitter (which sends signals) make up the VSAT outdoor unit (ODU), one of the two components of a VSAT earth station.

The second component of VSAT earth station is the indoor unit (IDU). The indoor unit is a small desktop box or PC that contains receiver and transmitter boards and an interface to communicate with the user's existing in-house equipment - LANs, servers, PCs, TVs, kiosks, etc. The indoor unit is connected to the outdoor unit with a pair of cables.

The key advantage of a VSAT earth station, versus a typical terrestrial network connection, is that VSATs are not limited by the reach of buried cable. A VSAT earth station can be placed anywhere - as long as it has an unobstructed view of the satellite. VSATs are capable of sending and receiving all sorts of video, data and audio content at the same high speed regardless of their distance from terrestrial switching offices and infrastructure.