Submarine Cable: Connecting Bangladesh to The World of High-Tech Information Technology
1. Introduction Now-a-days, the distance is not a factor because the technology makes the world a local place. Wherever you go, you are always connected to the people all over the world through the use of advanced communication technology. Yes, the communication system makes our life so easy that we can communicate anyone, anywhere in the planet. The word ‘Communication’ means the process of sharing ideas, information, and messages with others in a particular time and place. The communication can play a vital role on developing Information Technology and economical condition of developing country like Bangladesh. To improve the Information Technology and economical condition, we need faster and reliable communication. Submarine cable is the latest communication technology that can exchange the data at light speed (about 186,000 miles per second) and is most reliable and secured technology in the world. Submarine cable boosts the Information Technology and Economy of Bangladesh. figure: fiber optics
2. Fiber Optics and Its Function Fiber Optics is very thin, pliable tubes of glass that use light to carry signals. With nearly unlimited bandwidth, fiber optic cables have much greater capacity than other transmission lines. Fiber Optics transfers the data as form of light. To understand how the fiber optics work, we need to know the very basic property of light. Light travels in a straight line as long as it is moving through the same substance. When light entered into a substance of different density then it changes its direction which is known as Refraction property of light. If light passing through the higher density substance to lower density substance three possible things can be occurred. (a) If the angle of Incidence is smaller than the critical angle then the light refracts and moves closer to the surface. (b) If the angle of incidence is equal to the critical angle then the light bends and moves along the surface between two substances. (c) If incidence angle is greater than the critical angle then light come back to the same substance again.
Figure 1: Bending of Light Ray (Forouzan) Fiber Optics uses the property of light. Fiber Optics has core and cladding which are made of glass or plastic. The core is surrounded by the cladding which is less dense than the core. Electronics data are converted into light and beam into the core of the cable. This process is done so technically such that the light moving through the core is reflected off the cladding instead of being refracted into the cladding (Forouzan, 2006, p. 198).
Figure 2: Layers of Fiber Optics (Google) 
Figure 3: Data Transfer through Fiber Optics (Forouzan) 3. Bangladesh Introduced with Submarine Cable After a long time waiting, Bangladesh was finally signed in with submarine cable on March 27, 2004 and reached to its end user from June 2005. An organization named South East Asia-Middle East-West Europe-4 (SEA ME WE 4) connected Bangladesh and 12 others countries with high speed data communication facilities. The Organization SEA ME WE 4 ran the cable from Singapore cross through Malaysia, Thailand, Bangladesh, India, Sri-Lanka, Pakistan, a number of middle eastern countries and end in France. The submarine cable boosts Bangladesh internet connection speed 68 times faster than it was before. Bangladesh Telegraph and Telephone Board (BTTB) and more over 100 internet service providers (ISPs) have capacity to serve 150-megabyte per second data rate. Before submarine cable introduced to Bangladesh, ISPs companies were dependent on Singapore based satellite data transfer, which are still very costly. Now BTTB are offering more facilities than the satellite communications at least cost to ISP companies. Earlier Bangladesh had missed to connect with the submarine cable (SEA ME WE 3) with ran through the Bay of Bengal. Basically it happened because of wrong prediction and lacks of practical sense of the government that time (“Submarine and Bangladesh,” March 18, 2006). 4. Pros of Submarine Cable in Bangladesh Submarine cable has carried our communication system so far that it can be compared to any other developed country. This connection changes the dimension of communication environment that it was before in Bangladesh. This technology has brought many facilities like, high bandwidth, fast data transfer, immunity to interference and cross talk, secured and most of all reliable communication system. (a) Reliable CommunicationBangladesh is known as “Country of Rivers”. Unfortunately, Bangladesh is suffering from natural disaster like flood, every year. In rainy season, a huge area goes down under the water as the country is covered by the large numbers of rivers. The excessive rains fade the margin region; as a result, the performance of the satellite connection reduces rapidly. It is also happen that flood or any excessive water levels interference the propagation of satellite signals. These above are minor problems and the major problem that Bangladesh faced was in 1991. Cyclones knocked down several radio towers in Chittagong and whole country was detached from international links. All most every year natural disasters damage our radio towers, which are very expensive for the country like Bangladesh. Fiber optics connection does not require any tower, so it appears as the only one way solution for a continuous and reliable communication system in Bangladesh (Bashar, 2002). (b) Fast Data Transfer Before connected with submarine cable, Bangladesh used Copper wires as the backbone of the whole telecommunication network. Basically, Copper wires like Co-axial and twisted pair cables have less bandwidth than the fiber optics. Its mean copper wires have less data transfer rate than the fiber optics. Fiber optics passes the data at speed of light which is the greatest speed of the planet. (Forouzan, 2006, p. 202) (c) High Bandwidth After connected with the submarine cable, Bangladesh have a 10 gigabyte data transfer capacity a second which has boost the speed 68 times faster than before. Bangladesh Telegraph and Telephone Company and more than hundreds of ISPs now have 150 megabyte per second, where BTTB alone commands 83 megabyte per second capacity. This high bandwidth speed has boosted our browser speed, so we can share more information in less time (“Submarine and Bangladesh,” March 18, 2006). (d) Less Number of Regenerators Fiber optics covers the maximum transmission distance rather than any transmission medium. Fiber optics can carry signal up to 50 km without any regenerators where the cable Bangladesh used before required regenerators within every 5 km distance. The less number of regenerators saves huge amount money (Forouzan, 2006, p. 202) (e) Immunity to electromagnetic interference and SecurityFiber optics transfers the data in form of light. So, electromagnetic interference cannot affect the fiber optics. As copper transfer the data in form of electric current, by using electromagnetic field, data can be tapped from the cable. But there is no way of tapped the data from the fiber optics cable as it is converting the data in form of light. (Forouzan, 2006, p. 202) (f) Small size and weight An optical fiber is often no wider than the human hair. It is very small in size and less weight than the copper cables. Their size and weight is so convenient that it is not creating any congestion in cities (Basar, 2002). (g) Development in IT Sectors Submarine cable has shaped the future of Information Technology (IT) sectors. In Bangladesh there are many bright students who are interested about IT study. As Bangladesh has just introduced with this technology, we need man power for the maintenance purpose. A little afford in IT training can reduce the number of unemployed youth in the country and fill up the required man power. The demand of computer science and telecommunication study is rapidly increasing as the technology takes us to the new era of technical world. The job market of IT has become most demandable because submarine cable has made the IT sector much wider than before. 5. Cons of Submarine Cable in Bangladesh A word goes “Its easy to gain but hard to maintain.” Yes, Bangladesh has achieved the super highway communication but there are some major problems occurred in maintenance like: lacks of expert for technical support, cost of maintenance and the sabotaged of submarine cable for several times. (a) Lack of expert for technical support As Bangladesh is a new comer in the information highway system, it lacks the sufficient number of experts. After detached 22 times from the submarine cable we face the lacking of experts in Bangladesh (“Sabotaged,” November 14, 2007). As a result, we have to depend on the foreign experts. Lacks of local experts and dependency on foreign experts always takes huge time to recover the system which disrupts our communication system and slash huge amount of revenues of the government. (b) Cost of Maintenance The maintenance cost of submarine cable is a little bit expensive for Bangladesh. To get the continuous support from the submarine cable network, it needs continuous supply of the electricity to turn on the regenerators which are set 50 km apart from each other (Forouzan, 2006, p. 202). As Bangladesh is a less developed country, it is still unable to produce sufficient electricity that it’s needs. On the other hand taking help from the foreign experts increase the maintenance cost a lot. Disruption of several times causes great loss of the revenues. A statistics shows that the disruption deprive the BTTB of revenue of 70,000 US dollars per hour (“Sabotaged,” November 14, 2007). (c) Sabotaged of Submarine Cable Since the installation of the submarine cable in 2006 it has been disrupted for 22 times. Investigation says that BTTB itself shut down the line eight times for maintenance works and there had been seven cases of accidental disruption of the line. The remaining seven are being described as acts of sabotage (“Sabotaged,” November 14, 2007). Some personnel including illegal Voice over Internet Protocol (VOIP) operators are thought to be involved with the sabotage. Whatever the reasons behind this fact is that it is being snapped for their own interest and government must take steps against the so called disruption. 6. Ways to Prevent From Being Disrupted For getting continuous support of submarine cable connection government should take some steps to prevent the discontinuation of the system. As mentioned early, the cable has been disrupted for 22 times and the major reasons for this event are: 1) Sabotage by culprits. 2) Accidental disruption (a) Prevention from Being Sabotaged If we try to find out reasons behind the disruptions, firstly we see mischief by some self-seeking people. To prevent from being sabotaged special security system should be imposed by the government. Secondly, illegal VOIP operators who are thought may have the connection with the mischief cases should find out and take legal steps against them. Thirdly, if the government is even unable to maintain the sector then the government can give its responsibilities to a non government hand to take care of. (b) Backup Line for Fiber Optics Bangladesh Telegraph and Telephone Board had already proposed to the Power Grid Corporation of Bangladesh (PGCB) to back up its own network in case of any disruption of the network. PGCB has to support the Dhaka-Chittagong-Cox’s Bazar fiber optics of BTTB which is connected with the submarine cable. To obtain the facilities from the PGCB, BTTB have to pay 20 crore taka for five years. For this huge rental cost, the proposal was not implemented yet, but BTTB is expecting the deal will be soon finalize and serves continuous communication to the country. Meanwhile, BTTB is using extra microwave link for back up the service if any occurrences occurs (“PGCB,” November 11, 2007). 7. Tremendous Effect on Economy The advantage and benefits that telecommunication can play a vital role in education, commercial, medical and government activities. In other word, telecommunication can bring a tremendous effect in our national economy. Basically, communication system is one of the most important factors on with economical condition of a country depends. Improving the telecommunication system will reduce the cost of local and international phone calls to and from Bangladesh which enabling Bangladeshis to join the international community. (a) Fiber Optics replaces expensive Satellite communication Before the connection with the fiber optics, more than 100 internet service providers (ISP) were depended on the Singapore based satellite data transfer which is still very costly. Data transfer rate was quite slow and did not support high definition technologies that other side of the world was using by that time (Bashar, 2002). After the end of the long waiting session of fiber optics connection, Bangladesh Telegraph and Telephone Board got the authority of fiber optics when it has become a member of SEA ME WE -4 with 12 other countries. BTTB has 83-megabyte capacity and offering the ISP with lease facilities (“Submarine and Bangladesh,” March 18, 2006). Earlier the rental cost for using satellite based communication ISPs have to paid a huge amount of money to foreign countries but now , such facilities are provided by the BTTB and the rental expense are earned by the BTTB itself. As a result, ISPs are replaced the Very Small Aperture Terminal (VSAT) by fiber optics and the rental revenues are earned by the BTTB are improving our economical condition. (b) Increasing Number of ISP After getting connected to submarine cable the numbers of users are rapidly increasing. Significant improvements in performance of the internet technology influence the people to get connected to the world of communication. Voice and video conferencing, online games, chatting, and steaming videos direct from the internet all are granted as entertainment for the Bangladeshis. The number of users significantly increasing day by day which influence the ISP’s market grows. ISP has become one of the most profitable businesses in Bangladesh. At the very beginning journey of internet, the users of internet were few because of the high rate of internet access cost. Due to submarine cable’s support, ISPs are providing internet access cost at a minimum rate, so the number of users has increased noticeably. (c) Effects of IT on Economy Submarine cable has developed the IT sector of Bangladesh. The increasing number of ISPs provides the IT related jobs in Bangladesh which can reduce the numbers of unemployed. Many foreign companies are interested for investment to establish IT-enabled value added service like e-banking, call center, tele-medicine, and distance education at overseas universities. A rich IT sector can take a sleepy economy to an optimum state. In particular our neighbor country, India has achieved a tremendous success on its economy by the strong backing of IT industries. Requirements of Software experts and Electronics and Telecommunication engineers are mostly preferable. IT related education and training institutes are rapidly growing to fulfill the needs. 8. Conclusion Introduction of submarine cable network in Bangladesh is obviously a great achievement. It is a reliable communication system for Bangladesh, so far has made a great development of our IT sectors, taken our country in the home of information and boosting our economy through its fastest data transfer rate, increasing the number of ISP operators. It is a matter of great regret that our submarine cable network has disrupted a number of times by accidents or sabotages and we the Bangladeshi should take a proper care of this asset and make the best use of it. ReferencesBashar, S. A.(October 12, 2002). Fiber optic telecommunications in the context of Bangladesh. Retrieved November 20, 2007, from http://www.betelco.com/bd/bdstel/dstar.pdf Forouzan, B. A. (2006). Transmission media. Data communication and networking (4th ed.). (pp. 191- 212). New York: Tata McGraw- Hill. PGCB (November 11, 2007). BTTB to strike deal with PGCB on use of fiber optic cable. Retrieved December 16, 2007, from http://www.groundreport.com/article.php?articleID=2837837 Sabotaged. (November 14, 2007). Submarine cable link ‘sabotaged’ again. Retrieved November 28, 2007, from http://www.bangladeshnews.com.bd/2007/11/14/submarine-cable-link-sabotaged-again/ Submarine, and Bangladesh (November 14, 2007). Bangladesh finally logs on to submarine cable. Retrieved from http://www.asiamedia.ucla.edu/article.asp?parentid=9046 Appendix A Refraction of Light The direction of light propagation can be changed at the boundary of two media having different densities. This property is called refraction, and is illustrated in the following figure for the boundary between air and water.
Figure 3: Data Transfer through Fiber Optics (Forouzan) 3. Bangladesh Introduced with Submarine Cable After a long time waiting, Bangladesh was finally signed in with submarine cable on March 27, 2004 and reached to its end user from June 2005. An organization named South East Asia-Middle East-West Europe-4 (SEA ME WE 4) connected Bangladesh and 12 others countries with high speed data communication facilities. The Organization SEA ME WE 4 ran the cable from Singapore cross through Malaysia, Thailand, Bangladesh, India, Sri-Lanka, Pakistan, a number of middle eastern countries and end in France. The submarine cable boosts Bangladesh internet connection speed 68 times faster than it was before. Bangladesh Telegraph and Telephone Board (BTTB) and more over 100 internet service providers (ISPs) have capacity to serve 150-megabyte per second data rate. Before submarine cable introduced to Bangladesh, ISPs companies were dependent on Singapore based satellite data transfer, which are still very costly. Now BTTB are offering more facilities than the satellite communications at least cost to ISP companies. Earlier Bangladesh had missed to connect with the submarine cable (SEA ME WE 3) with ran through the Bay of Bengal. Basically it happened because of wrong prediction and lacks of practical sense of the government that time (“Submarine and Bangladesh,” March 18, 2006). 4. Pros of Submarine Cable in Bangladesh Submarine cable has carried our communication system so far that it can be compared to any other developed country. This connection changes the dimension of communication environment that it was before in Bangladesh. This technology has brought many facilities like, high bandwidth, fast data transfer, immunity to interference and cross talk, secured and most of all reliable communication system. (a) Reliable CommunicationBangladesh is known as “Country of Rivers”. Unfortunately, Bangladesh is suffering from natural disaster like flood, every year. In rainy season, a huge area goes down under the water as the country is covered by the large numbers of rivers. The excessive rains fade the margin region; as a result, the performance of the satellite connection reduces rapidly. It is also happen that flood or any excessive water levels interference the propagation of satellite signals. These above are minor problems and the major problem that Bangladesh faced was in 1991. Cyclones knocked down several radio towers in Chittagong and whole country was detached from international links. All most every year natural disasters damage our radio towers, which are very expensive for the country like Bangladesh. Fiber optics connection does not require any tower, so it appears as the only one way solution for a continuous and reliable communication system in Bangladesh (Bashar, 2002). (b) Fast Data Transfer Before connected with submarine cable, Bangladesh used Copper wires as the backbone of the whole telecommunication network. Basically, Copper wires like Co-axial and twisted pair cables have less bandwidth than the fiber optics. Its mean copper wires have less data transfer rate than the fiber optics. Fiber optics passes the data at speed of light which is the greatest speed of the planet. (Forouzan, 2006, p. 202) (c) High Bandwidth After connected with the submarine cable, Bangladesh have a 10 gigabyte data transfer capacity a second which has boost the speed 68 times faster than before. Bangladesh Telegraph and Telephone Company and more than hundreds of ISPs now have 150 megabyte per second, where BTTB alone commands 83 megabyte per second capacity. This high bandwidth speed has boosted our browser speed, so we can share more information in less time (“Submarine and Bangladesh,” March 18, 2006). (d) Less Number of Regenerators Fiber optics covers the maximum transmission distance rather than any transmission medium. Fiber optics can carry signal up to 50 km without any regenerators where the cable Bangladesh used before required regenerators within every 5 km distance. The less number of regenerators saves huge amount money (Forouzan, 2006, p. 202) (e) Immunity to electromagnetic interference and SecurityFiber optics transfers the data in form of light. So, electromagnetic interference cannot affect the fiber optics. As copper transfer the data in form of electric current, by using electromagnetic field, data can be tapped from the cable. But there is no way of tapped the data from the fiber optics cable as it is converting the data in form of light. (Forouzan, 2006, p. 202) (f) Small size and weight An optical fiber is often no wider than the human hair. It is very small in size and less weight than the copper cables. Their size and weight is so convenient that it is not creating any congestion in cities (Basar, 2002). (g) Development in IT Sectors Submarine cable has shaped the future of Information Technology (IT) sectors. In Bangladesh there are many bright students who are interested about IT study. As Bangladesh has just introduced with this technology, we need man power for the maintenance purpose. A little afford in IT training can reduce the number of unemployed youth in the country and fill up the required man power. The demand of computer science and telecommunication study is rapidly increasing as the technology takes us to the new era of technical world. The job market of IT has become most demandable because submarine cable has made the IT sector much wider than before. 5. Cons of Submarine Cable in Bangladesh A word goes “Its easy to gain but hard to maintain.” Yes, Bangladesh has achieved the super highway communication but there are some major problems occurred in maintenance like: lacks of expert for technical support, cost of maintenance and the sabotaged of submarine cable for several times. (a) Lack of expert for technical support As Bangladesh is a new comer in the information highway system, it lacks the sufficient number of experts. After detached 22 times from the submarine cable we face the lacking of experts in Bangladesh (“Sabotaged,” November 14, 2007). As a result, we have to depend on the foreign experts. Lacks of local experts and dependency on foreign experts always takes huge time to recover the system which disrupts our communication system and slash huge amount of revenues of the government. (b) Cost of Maintenance The maintenance cost of submarine cable is a little bit expensive for Bangladesh. To get the continuous support from the submarine cable network, it needs continuous supply of the electricity to turn on the regenerators which are set 50 km apart from each other (Forouzan, 2006, p. 202). As Bangladesh is a less developed country, it is still unable to produce sufficient electricity that it’s needs. On the other hand taking help from the foreign experts increase the maintenance cost a lot. Disruption of several times causes great loss of the revenues. A statistics shows that the disruption deprive the BTTB of revenue of 70,000 US dollars per hour (“Sabotaged,” November 14, 2007). (c) Sabotaged of Submarine Cable Since the installation of the submarine cable in 2006 it has been disrupted for 22 times. Investigation says that BTTB itself shut down the line eight times for maintenance works and there had been seven cases of accidental disruption of the line. The remaining seven are being described as acts of sabotage (“Sabotaged,” November 14, 2007). Some personnel including illegal Voice over Internet Protocol (VOIP) operators are thought to be involved with the sabotage. Whatever the reasons behind this fact is that it is being snapped for their own interest and government must take steps against the so called disruption. 6. Ways to Prevent From Being Disrupted For getting continuous support of submarine cable connection government should take some steps to prevent the discontinuation of the system. As mentioned early, the cable has been disrupted for 22 times and the major reasons for this event are: 1) Sabotage by culprits. 2) Accidental disruption (a) Prevention from Being Sabotaged If we try to find out reasons behind the disruptions, firstly we see mischief by some self-seeking people. To prevent from being sabotaged special security system should be imposed by the government. Secondly, illegal VOIP operators who are thought may have the connection with the mischief cases should find out and take legal steps against them. Thirdly, if the government is even unable to maintain the sector then the government can give its responsibilities to a non government hand to take care of. (b) Backup Line for Fiber Optics Bangladesh Telegraph and Telephone Board had already proposed to the Power Grid Corporation of Bangladesh (PGCB) to back up its own network in case of any disruption of the network. PGCB has to support the Dhaka-Chittagong-Cox’s Bazar fiber optics of BTTB which is connected with the submarine cable. To obtain the facilities from the PGCB, BTTB have to pay 20 crore taka for five years. For this huge rental cost, the proposal was not implemented yet, but BTTB is expecting the deal will be soon finalize and serves continuous communication to the country. Meanwhile, BTTB is using extra microwave link for back up the service if any occurrences occurs (“PGCB,” November 11, 2007). 7. Tremendous Effect on Economy The advantage and benefits that telecommunication can play a vital role in education, commercial, medical and government activities. In other word, telecommunication can bring a tremendous effect in our national economy. Basically, communication system is one of the most important factors on with economical condition of a country depends. Improving the telecommunication system will reduce the cost of local and international phone calls to and from Bangladesh which enabling Bangladeshis to join the international community. (a) Fiber Optics replaces expensive Satellite communication Before the connection with the fiber optics, more than 100 internet service providers (ISP) were depended on the Singapore based satellite data transfer which is still very costly. Data transfer rate was quite slow and did not support high definition technologies that other side of the world was using by that time (Bashar, 2002). After the end of the long waiting session of fiber optics connection, Bangladesh Telegraph and Telephone Board got the authority of fiber optics when it has become a member of SEA ME WE -4 with 12 other countries. BTTB has 83-megabyte capacity and offering the ISP with lease facilities (“Submarine and Bangladesh,” March 18, 2006). Earlier the rental cost for using satellite based communication ISPs have to paid a huge amount of money to foreign countries but now , such facilities are provided by the BTTB and the rental expense are earned by the BTTB itself. As a result, ISPs are replaced the Very Small Aperture Terminal (VSAT) by fiber optics and the rental revenues are earned by the BTTB are improving our economical condition. (b) Increasing Number of ISP After getting connected to submarine cable the numbers of users are rapidly increasing. Significant improvements in performance of the internet technology influence the people to get connected to the world of communication. Voice and video conferencing, online games, chatting, and steaming videos direct from the internet all are granted as entertainment for the Bangladeshis. The number of users significantly increasing day by day which influence the ISP’s market grows. ISP has become one of the most profitable businesses in Bangladesh. At the very beginning journey of internet, the users of internet were few because of the high rate of internet access cost. Due to submarine cable’s support, ISPs are providing internet access cost at a minimum rate, so the number of users has increased noticeably. (c) Effects of IT on Economy Submarine cable has developed the IT sector of Bangladesh. The increasing number of ISPs provides the IT related jobs in Bangladesh which can reduce the numbers of unemployed. Many foreign companies are interested for investment to establish IT-enabled value added service like e-banking, call center, tele-medicine, and distance education at overseas universities. A rich IT sector can take a sleepy economy to an optimum state. In particular our neighbor country, India has achieved a tremendous success on its economy by the strong backing of IT industries. Requirements of Software experts and Electronics and Telecommunication engineers are mostly preferable. IT related education and training institutes are rapidly growing to fulfill the needs. 8. Conclusion Introduction of submarine cable network in Bangladesh is obviously a great achievement. It is a reliable communication system for Bangladesh, so far has made a great development of our IT sectors, taken our country in the home of information and boosting our economy through its fastest data transfer rate, increasing the number of ISP operators. It is a matter of great regret that our submarine cable network has disrupted a number of times by accidents or sabotages and we the Bangladeshi should take a proper care of this asset and make the best use of it. ReferencesBashar, S. A.(October 12, 2002). Fiber optic telecommunications in the context of Bangladesh. Retrieved November 20, 2007, from http://www.betelco.com/bd/bdstel/dstar.pdf Forouzan, B. A. (2006). Transmission media. Data communication and networking (4th ed.). (pp. 191- 212). New York: Tata McGraw- Hill. PGCB (November 11, 2007). BTTB to strike deal with PGCB on use of fiber optic cable. Retrieved December 16, 2007, from http://www.groundreport.com/article.php?articleID=2837837 Sabotaged. (November 14, 2007). Submarine cable link ‘sabotaged’ again. Retrieved November 28, 2007, from http://www.bangladeshnews.com.bd/2007/11/14/submarine-cable-link-sabotaged-again/ Submarine, and Bangladesh (November 14, 2007). Bangladesh finally logs on to submarine cable. Retrieved from http://www.asiamedia.ucla.edu/article.asp?parentid=9046 Appendix A Refraction of Light The direction of light propagation can be changed at the boundary of two media having different densities. This property is called refraction, and is illustrated in the following figure for the boundary between air and water. 
The apparent and actual positions of the fish differ because the direction of light propagation has been changed as light passes from the more dense water into the less dense air. If we adopt the convention that the light passes from medium 1 into medium 2, the general rule is that the refraction is • Away from the perpendicular if medium 2 is less dense than medium 1 • Toward the perpendicular if medium 2 is more dense than medium 1 Thus, in the above example the refraction is away from the perpendicular because air is less dense than water. Such effects form the basis of the refracting telescope, and of optical devices using lenses in general. Appendix B About SEA ME WE-4 The South East Asia-Middle East-West Europe 4 (SEA-ME-WE 4) project is the fourth project in the SEA-ME-WE series. On 27th March 2004, a consortium of 16 international telecommunications companies signed construction and maintenance agreements for the new optical fibre submarine cable system linking South East Asia to Europe via the Indian Sub-Continent and Middle East with Terminal Stations in Singapore, Malaysia, Thailand, Bangladesh, India, Sri Lanka, Pakistan, United Arab Emirates, Saudi Arabia, Egypt, Italy, Tunisia, Algeria and France. The contract is being awarded jointly to Alcatel Submarine Networks, France and Fujitsu Ltd., Japan and the estimated project cost is of the order of US$ 500 million. The total length of the SEA-ME-WE 4 submarine cable system will span approximately 20,000 km which consists of the main backbone across the Eastern and Western worlds plus the extension links in various countries. The project will support telephone, internet, multimedia and various broadband data applications. The SEA-ME-WE 4 submarine cable will benefit hundreds of millions of people communicating along the route between Singapore, France and beyond. The construction of this cable system is testimony to the growing demand for high capacity broadband links that are essential in today’s world of high speed international connectivity and online business. Many developing markets are expected to see strong growth in the short term as efforts are made to improve and expand the broadband technology infrastructure.
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