Security Model for Educational Satellite Networks

Education has been the greatest tool for human resources development. The advances in information and communication technology has brought out a paradigm shift in the educational sector by making it more accessible, relevant, qualitative, and equitable for the masses. The use of satellite technology like INTELSAT, PEACESAT, and ATS in education has enhanced the opportunities for learners to acquire new skills (Moore & Kearsley, 1996). Both on-campus and distance mode students can be benefited by it. The satellite technology can serve a large geographical area. It allows audio and video signals uplinked from a station to be received to any number of downlink earth stations (Willis, 1995). Oliver (1994) reported that the transmission costs do not increase with the increase in the number of downlink stations. Satellite Instructional Television Experiment (SITE), one of the India’s early experiments conducted during 1975 to 1976, produced and transmitted 150 different science programs of 10 to 12 minutes duration, offering them to more than 2,330 villages in six geographical clusters. According to Shrestha (1997) and Govindaraju and Banerjee (1999), this experiment demonstrates the effectiveness of satellite communication for educational purposes. EduSat is the first exclusive educational satellite of India (www.edusatindia.org and www.ignou.ac.in), especially designed to provide satellitebased education through the audio-visual medium by employing DTH (direct-to-home) quality broadcast (www. edusatindia.org). A complete nationwide coverage is ensured through multiple regional beams. There are five Ku-band transponders with spot beams covering northern, northeastern, eastern, southern, and western regions of India. The entire Indian mainland is covered through the footprint of one national beam of a Kuband transponder and six channels through extended C-band transponders. A two-way video communication system, Space Collaboration System (SCS), is being used as a cooperative distance education project between Japan, China, and Thailand (Tanigawa, Ileura, Anzai, & Kaneko, 2002). A Direct Broadcast Satellite (DBS) is being used extensively in the United States by the learners to receive educational programs at home or offices through a small inexpensive satellite dish, which soon would take over video broadcasting and narrowcasting (Moore & Kearsley, 2005). The University of the South Pacific also offers distance education to its 12 member countries through its own satellite communication network (USPNet) (see http:// www.usp.ac.fj). USPNet is used for audio conferencing among various campuses, and video broadcast of live or pre-recorded lectures.