1、http:/ go to http:/ where you can download million word documents .1Utilizing Very Small Aperture Terminal (VSAT) Technology Infrastructure in African SchoolsThis word document was downloaded from the website: http:/ please remain this link information when you reproduce , copy, or use it.word docum
2、entsBy Ebenezer Malcolm*AbstractRecent changes in Information Communication Technologies (ICTs) are transforming industrial countries schools, management practices, and the structure of national and global economies. A new divide is being created between the information-rich economies and slow-movin
3、g information-poor economies such as African countries. In addition, a new type of global inequality is also rapidly emerging between those countries that are linked into the global networks and those that are not. Unfortunately, Africa lags behind the rest of the world in every dimension of this te
4、chnological revolution. Lack of modern telecommunication infrastructures in Africa continues to hinder socio-economic development. According to World Bank, the cost of Internet connectivity for example is a serious barrier to education in virtually every African country (World Bank 1996).1 A commerc
5、ial dial-on-demand Internet in Ghana costs US$ 55/month, not including underlying telecommunication costs in Kenya such costs are US$30-40/month. In Namibia, the cheapest commercial dial-on-demand Internet service costs US$15/month2. 1 See World Bank (1996) “Partnership for Capacity Building in Afri
6、ca“. A Report of the African Governors of the World Bank to Mr. Wolfensohn, by then President of World Bank. 2 See SchoolNet Namibia realities (p.14) at http:/www.schoolnet.na/news/ICTworkfacereality.pdf Retrieved on 5/1/2006 http:/ go to http:/ where you can download million word documents .2There
7、is the need for Africa countries to put in place strategies to catch up with the rest of the world in modern ICT infrastructure innovative technology. A classical example of such an infrastructure is the Very Small Aperture Terminal (VSAT) Technology. Africa countries can utilize VSAT technology to
8、enhance electronic learning in schools. The paper first explains how the VSAT technology works. It also gives a brief historical background and the principal parties behind the technology. The paper also focuses on the relevance of the technology and its socio-economic implications to African school
9、s. Furthermore, the paper dwells on some barriers or limitations of the deployment of the technology. Finally, the paper focuses on the way forward for the utilization of the technology.What is VSATVSAT is an acronym that stands for the Very Small Aperture Terminal. A VSAT is defined as a “fixed ear
10、th Station with an antenna diameter less than 2.4 meters that is suitable for easy installation on consumer premises” (Adamson, S., et al, 1995, p.182).3 According to Global VSAT forum, the “term refers to any fixed satellite terminal that is used to provide interactive or receive-only communication
11、s.”4 According to Flournoy (2004), “VSAT networks consist of user located terminals and software pointing to affiliated satellites that have been programmed to seamlessly interconnect large and small organizations.”5 3 See Adamson S., et al., (1995) Advanced Satellite Communications: Potential Marke
12、ts: New Jersey: Noyes Data Corporation (p.182)4 See GlobalVAT Forum website Retrieved on 4/18/06: http:/www.gvf.org/vsat_industry/whatis/index.cfm?CFID=515881 where low-cost receive-only satellite dishes are combined with the use of dialup telephone or mobile networks for the return path to the Inte
13、rnet. Point to point type is that which involves only two terminals communicating directly with each other over a dedicated channel. Common applications include sending news reports from the field back to a central studio or providing telecommunication services to remote areas from a central switch,
14、 such as extending the telephone connection to a remote town using VSATs and providing large amounts of bandwidth to Internet Service Providers. The Star type of network is the one similar to a wheels hub and spokes with several VSAT stations communicating through a central facility (the hub), which
15、 regulates and controls communications. This is the more common network topology in use. The advantage of this topology is that the individual VSAT terminals can be kept relatively small, provided that a large dish (typically over 5 meters) is used at the hub.7 Ibid (p.23)8 See Adamson S., et al., (
16、1995) Advanced Satellite Communications: Potential Markets: New Jersey: Noyes Data Corporation (p.182)http:/ go to http:/ where you can download million word documents .5The Mesh network type of VSAT has the ability to communicate directly with one another without going through a central hub. As suc
17、h, mesh networks are also referred to as “hub-less networks”. This type of network requires relatively larger and more sophisticated VSAT terminals and indoor equipment which increases the start up costs. However, it is ideal for real time communications, such as telephony, among two or more locatio
18、ns in the same network. The fifth type of VSAT is the hybrids network. As the name implies, this is a blend or combination of star and mesh types. In a typical setup, most stations could communicate through a hub, with a few stations having the ability to communicate directly with one another, witho
19、ut going through the hub (.Twinomugisha, and Aluoch 2005)9Historical Background and Principal Players of VSAT Technology in AfricaHughes Network System of Germantown, Maryland, invented the VSAT in 1983 and soon thereafter launched the satellite networks industry with the first system sale to Wal-Ma
20、rt. Since that time it has continually invested in design and development of innovative satellite networking products and services, consistently maintaining its global market share leadership of over fifty-five percent. To date, Hughes has sold over 1 million systems to enterprise, government and co
21、nsumer and small business customers in over 100 countries.10 The company also sold the equipment to banks, pharmaceutical companies, oil and gas retailers, and educational institutions among others.11 When the company changed status to GM/Hughes, it introduced DirecTV and PC services that provided I
22、nternet services to its customers. Later, New Skies Company of Netherlands in 9 Twinomugisha, A. and Aluoch, S. (2005) The VSAT Buyers Guide: Ottawa: IDRC (p.28-33)10 See Hughes website at . Retrieved on 4/19/0611 See Flounory, D. (2004) The Broadband Satellite Millennium: Communication Technologies
23、 and Markets: Chicago: IEC (p.220)http:/ go to http:/ where you can download million word documents .6collaboration with Intelsat introduced VSAT services into the Africas market (Flournoy, 2004).12 Currently, there are major satellite companies operating in Africa. Notable among them are: Hughes Ne
24、twork Systems, LLC (HUGHES)Hughes Network Systems is the pioneer and global leader in providing broadband satellite networks and services for large enterprises, governments, small businesses, and consumers. Hughes has been supporting Africas telecommunications needs since the early days of the compa
25、ny, designing networking solutions to meet the unique requirements of African companies. Hughes maintains staff on the continent and in France to ensure the highest level of service for both English- and French-speaking customers. Using its VSAT satellite technology, Hughes has long offered communic
26、ations solutions for urban and rural applications, both throughout the African continent and as a gateway for international applications. Hughes advanced communications systems are based on VSAT satellite technology and Hughes Net high-speed broadband services. These networks transmit high-speed IP
27、multimedia, data, video, and voice, enabling businesses in Africa and the Middle East to improve operating efficiencies while offering an array of customer services not possible only a few years ago. Hughes presently holds more than fifty percent share of the African VSAT market.13Arab Satellite Com
28、pany (Arabsat)Arabsat was established in 1976. The company is the leading provider of satellite communications to the Arab Communities in the Middle East. Ranked as the 10th Satellite Operator globally, Arabsat continues to offer its customers multi-mission 12 Ibid (p.221-222)13 See Hughes website a
29、t . Retrieved on 4/19/06http:/ go to http:/ where you can download million word documents .7satellite services, such as television, telephony, Internet and the provision of VSAT and other interactive services that meet both current and emerging demands of Arabsat customers. Arabsat operates a fleet
30、of 6 satellites (4 of which are fully owned) providing capacity to media and entertainment companies, corporate and government entities, and IP and Broadband Internet access organizations. Arabsats satellites provide coverage to more than 100 countries of millions of homes covering the Middle East,
31、Africa and the major parts of Europe. Arabsat connects the world via its global platform partnering with the worlds leaders in satellite communications, reaching its customers to their final destinations, any time, and any where.14Regional African Satellite Communications Organization (RASCOM)Region
32、al African Satellite Communications Organization (RASCOM) was established in 1992. RASCOM is an intergovernmental, commercially run organization whose capital opens to the private sector to design, implement, operate and maintain the space segment of the African telecommunications satellite system a
33、nd translate into services and tools for African integration. RASCOM main goals are: To provide an affordable infrastructure on a large scale to rural areas of the continent by using appropriate technology. Secondly, to improve and develop inter-urban communications in each country. Thirdly, to esta
34、blish direct links between all African countries without exception.14 See Arabsat website::Retrieved on 4/19/2006http:/ go to http:/ where you can download million word documents .8RASCOM also intends to provide a range of services, voice, data, multi-media, tele-education, tele-medicine, video conf
35、erencing among others to African countries.RASCOM has a total coverage of the entire continent of Africa (including its islands) - from Mauritius to Cape-Verde and from Cape Town, South Africa to Tunis, Tunisia. It also offers universal access to telecommunication services to nearly 700 million peop
36、le of Africa with ground terminals having capabilities to accommodate telephony, fax, Internet/data and TV simultaneously to Africa countries. RASCOM provides connectivity on demand services (DAMA) which guarantee direct link from any country to all other countries in the continent, irrespective of
37、the volume of traffic.15Pan American Satellite Company (PanAmsat)PanAmSat provides global video and data broadcasting services via satellite and fiber technology. PanAmsat network reaches nine-eight percent of the worlds population, and distributes entertainment and information for cable television
38、systems; TV broadcast affiliates, direct-to-home TV operators, Internet Service Providers, telecommunications companies and corporations. PanAmsat have a strong tradition in Africa of pioneering and expanding the delivery of comprehensive satellite-based communications services throughout the expans
39、ive continent. Since the launch of PAS-4 in 1995, the first commercial satellite to deliver services throughout Africa, the company now operates five spacecrafts offering coverage from Algeria to South Africa, Senegal to Somalia.16 New Skies Satellite Company15 See RASCOM website at www.rascom.org.
40、Retrieved on 4/19/0616 See PanAmsat website at . Retrieved on 4/19/2006http:/ go to http:/ where you can download million word documents .9New Skies operates the youngest fleet of the four global satellite communications companies and has built a network of strategically located, owned and affiliate
41、d media ports to provide access to our satellites from every region of the world. From eight offices worldwide, the company offers more than 250 customers based in seventy-nine countries the state-of-the-art, commercially driven services and strong customer focus that have made the company a premier
42、 provider of satellite communications services in Africa. Opening up new opportunities for broadcasters, telecommunication companies and Internet service providers who want to reach the most populous and important markets of sub-Saharan Africa, NSS-7 provides an extensive range of in-region and tran
43、s-Atlantic connectivity options. With larger Ku-band footprints over Southern Africa and Western Africa, as well as powerful C-band transmission power, NSS-7 provides nearly complete continental coverage with outstanding power and performance. The signals can be in Ku-band for Direct-To-Home (DTH) t
44、elevision transmission or in C-band for re-transmission by terrestrial channels or by other professional users such as Internet and telecom providers.Relevance of VSAT Technology to African SchoolsVSATs technology could be used to provide Internet-based services to African schools where the local te
45、lecommunication companies infrastructure are non-existent, very expensive or unreliable. In addition, it could be used to provide telephone services to remote or rural African schools. For example, VSATs have been used successfully in remote schools in Uganda, Zimbabwe and Namibia schools. It is wor
46、th noting that Uganda is one of the first African countries to use VSAT technology in rural schools. It is worth noting that fifteen rural schools were linked via VSAT technology.1717 See School net Uganda website at http:/www.schoolnetuganda.sc.ug/homepage.php?option=vsatproject http:/ go to http:/
47、 where you can download million word documents .10The reliance on VSAT technology could ensure flexibility and scalability and enables the seamless integration and delivery of different content formats e.g. video, voice and multimedia data on a single medium. In addition, VSAT systems can improve ge
48、neral connectivity and enable fast and efficient delivery of other content such as video, voice and data to African schools computer laboratories, learning centers, and libraries among others. For example a mixture of videotaped and live lectures delivered by one-way video, 2-way audio digital satellite broadcast (MPEG-2 DVB) and e-mail interaction between stu
