|Internet over satellite system|
|Saturday, 12 August 2006|
The Internet has a plurality of computer systems which are generally interconnected to each other using local area networks and dedicated transmission lines to form a wide area network of computers. Internets may employ a variety of electronic transport media, such as telephone lines, optical fiber, satellite systems, local area networks, etc. The most common method of sending and receiving computer information today is a land line service (i.e., a switched service, a dedicated line, and/or an analog modem, each using telephone wire lines). Entry into the Internet is furnished by Internet service providers (ISPs). ISPs operate networks that connect with each other at network access points (NAPs). Information is transmitted between NAPs in the form of individual data packets. Each packet contains an embedded source and destination address to which the packet is routed across the networks. An important feature of the global Internet is the ability to make a large amount of information available to many users. However, internet service providers cannot offer a high grade of Internet service irrespective of geographical regions.
With the advent of satellite-based communications systems, access to computer networks such as the Internet and in particular the worldwide web, can now readily be achieved by mobile users through the use of lap top computers or other portable terminals such as cell phones. Geostationary earth orbit (GEO) allows a satellite to orbit the earth at a fixed location in relation to the earth. Increasingly, GEO-based satellite communications systems are being made to be compliant with the International DVB standard, principally intended for digital television broadcasting but now also embracing the Internet communication protocol TCP/IP. Satellite communication receivers are commonly used to create or supplement existing private wide area data and video networks. When used as an extension to a data network, these satellite links may interconnect local area networks. Satellite links can provide many advantages over land line service, including potentially high speed data transmission and wide availability. Satellite Internet access is currently available and has found favorable market acceptance. Satellite communications offer sufficient bandwidth for remote multimedia applications that require high data rates in both directions include video conferencing, LAN/WAN systems, Internet applications, document delivery, audio applications such as internet phone, terminal equipment, commercial web sites, online gaming, point of presence, net Meeting and collaboration software.
Satellite data systems provide a solution to the consumer seeking broadband Internet connectivity where no terrestrial alternatives such as cable or telephone line based broadband service are available. However, typical satellite links have required expensive hardware both to transmit and to receive data. The expense of the hardware has made the use of satellite communication channels generally unavailable to those who most need it. A relatively large amount of transmission power is needed due to the long distances involved and a large dish may be required for sending and receiving, especially to achieve high data rates. Current commercially available Internet via satellite solutions are based on an asymmetrical approach in which the data link to the user is via satellite while the return link to the user is via telephone lines using commercially available telephony modems. The data rate of asymmetric internet via satellite communication systems are basically for e-mail and browsing applications only.