VSAT FAQ

15 Frequently Asked Questions about VSAT!


1. What does VSAT stand for?
VSAT is short for Very Small Aperture Terminal

2. What is a VSAT?
A VSAT is a small-sized telecommunications earth station that can give access to the Internet and transmits and receives data, voice, fax, or video conferencing via satellite. The satellite dish diameter is typically 1.2-1.8 meters for Ku-band systems, and 1.8-2.4 meters for C-band systems.

3. How does a VSAT network look?
VSAT networks come in various shapes and sizes ranging from a star topology system with an operator's shared hub serving many thousands VSATs located at the customers' site. Mesh systems, where individual VSATs can send and receive traffic to/from other VSATs, have traditionally been somewhat smaller in size than star systems, but the average size of orders has risen as prices have gone down and some rural telephony networks now comprise as many as several hundred or even thousands of sites.

4. For what are VSATs used?
VSAT systems generally connect a large number of geographically dispersed sites to a central location. VSAT networks may transmit Internet, voice, data, fax, or video conferencing over great distances –regardless of topography and infrastructure.

5. Which companies use VSAT systems?
Companies and organizations in various industries and sectors use VSAT –ranging from banks, insurance companies, healthcare companies, manufacturers, couriers, telephone companies, national defense, transport business, electrical utilities, oil and gas pipelines, energy production and exploration, non-governmental organizations, various government departments and agencies –and many more!

6. What are the components in a VSAT site?
A typical VSAT site consists of a parabolic-shaped antenna mounted on the roof of a building, connected by a cable to a chassis inside the building. The size og the indoor unit is similar to that of a laptop PC. TELE Greenland International's technicians or the customer's own technicians install these antennas at customer sites. The customer will be connected via one of TGI's portfolio of satellites.

7. What does the VSAT unit contain?
A typical VSAT unit contains a modem for translating satellite transmissions into data and vice versa and terrestrial interfaces for connecting customer equipment. The TGI VSAT also performs such functions as dynamic bandwidth allocation and TCP acceleration for Internet applications and QoS for telephony applications.

8. How do I register VSAT?
TELE Greenland International will in conjunction with the customer and local authorities take care of the registration according to the customer's specific VSAT requirements.

9. How long does it take to install a VSAT system?
After a preliminary site survey, the actual installation and line-up can be completed in a few hours. The whole installation typically takes about three days.

10. What do I need to prepare before installing a VSAT system?
You need space to erect the antenna that ranges from 1.8 to 2,4 meters in diameter. This space needs to be verified by our field technician to ensure that there is no nearby obstruction such as trees or buildings that may block the line-of-sight to the satellite. The installation is relatively simple; similar to setting up a parabola antenna for receiving TV satellite broadcasts.

11. How secure is a VSAT network?
The transmission in a VSAT network is done in digital and the network traffic is scrambled. The TGI VSAT can be provided with encryption (3 DES). Our VSAT system haS been trusted by defense to carry information.

12. Do I need to install an external router to setup IP network over the VSAT?
TELE Greenland International's VSAT system is designed around IP network. Our system is highly optimized with built-in IP bridging/routing, packet prioritization, packet compression, protocol spoofing, and remote LAN monitoring. Therefore, the VSAT unit is already functioning as a router. The remote unit has a built-in 10Base-T and 100Base-TX RJ45 socket.

13. Can I connect to the Internet via TGI's VSAT?
Because the VSAT system is IP-enabled, you can connect it to the Internet via the VSAT. Our VSAT system supports asymmetric bandwidth utilization. Therefore, you may be able to take advantage of this feature to support the asymmetric nature of Internet access. We are able to provide outbound of up to 11 Mbps and inbound of up to 6 Mbps.

14. How big a problem is satellite delay?
The distance that the signal travels from the VSAT unit to the satellite causes the satellite delay. This ¼ second delay is present in all satellite-based services including some of the long-distance phone call that we use today. The throughput performance however, remains unaffected. A single hop delay is the delay caused by the transmission from a VSAT unit to another unit. However, certain VSAT topology uses the master hub-station as the transit gateway to connect between two remote units, which introduce a two-hop delay for each transmission. Voice calls are especially sensitive to the delay problem. The TGI VSAT will soon have star-mesh capability supporting both VSAT-HUB and VSAT-VSAT traffic.

15. What is the coverage area of TGI's VSAT solutions?
We almost cover the entire globe!