Satellite Overview

VSAT

VSAT stands for “Very Small Aperture Terminal” and refers to receive/transmit terminals installed at dispersed sites connecting to a central hub via satellite using small diameter antenna dishes.

VSAT technology represents a cost effective solution for users seeking an independent communications network connecting a large number of geographically dispersed sites. VSAT networks offer value-added satellite-based services capable of supporting the Internet, data, LAN, voice/fax communications, and can provide powerful, dependable private and public network communications solutions.

Generally, these systems operate in the Ku-band frequencies. Ku-band based networks, are used primarily in Europe and North America and utilize the smaller sizes of VSAT antennas.

VSAT networks come in various shapes and sizes ranging from point-to-point, point-to-multipoint, and on demand for thousands of sites based on a dedicated facility located at their own site. Mesh systems have traditionally been somewhat smaller in size than star systems - 5 to 30 sites used to be a good rule of thumb - but since prices have come down, some networks now comprise as many as several hundred or even thousands of sites.

Point to point

If there were a requirement to support voice and data in a classic point "A" to point "B" network—from one city to another, for example—point-to-point/SCPC technology would typically be used. In this scenario, a standard data/voice multiplexer would be connected to a standard, off-the-shelf SCPC satellite modem for each end of the circuit. This is a very simple and inexpensive approach for point-to-point voice and data networks and is used extensively. Unfortunately, however, this approach cannot adequately handle multi-point networks, which is where Sky Performer excels. What are some of the problems with point-to-point/SCPC technology? The point-to-point/SCPC approach is often used to build small point-to-multi-point star networks. For example, if there were a central site that needed to communicate with six remote locations, it would be necessary to put a muxtiplexer and SCPC satellite modem pair at each end of the six links. At the central site there would be one multiplexer and six satellite modems. If a seventh location were to be added, an additional satellite modem would have to be added to the central site. This is a very cumbersome and costly approach to building small to medium size networks. such an approach requires a lot of hardware at the central site.

Point to Multipoint

ATC offers a two way Point-to-Multipoint (P2MP) advanced Single Carrier Per Channel (SCPC) service. It combines state of the art VSAT technology with unparalleled VPN (virtual private network) security. ATC enables customers to connect remote operations directly to their head offices with absolute security. Multiple locations may be connected in a star topology. VPN interconnectivity between locations enables voice, data, e-mail and Intranet applications.