Nets, Webs and the Information Infrastructure/Enter the Net
What is information and communications technology?
[edit | edit source]From the Merriam-Webster OnLine Dictionary (http://www.webster.com), we have the following definitions:
- Information - the reception of knowledge or intelligence
- Communication - an act or instance of transmitting; a process by which information is exchanged between individuals through a common system of symbols, signs, or behavior
- Technology - a manner of accomplishing a task especially using technical processes, methods, or knowledge
Information and communications technology (ICT) refers to a broad field encompassing software, hardware, computers and networks. It includes communication infrastructure and technologies such as regular telephony, cellular networks, satellite communication, broadcasting media, and other forms of communication.
What is the Internet?
[edit | edit source]The Internet is by far the fastest growing information and communications medium. There has been a phenomenal growth in the number of users, extent of infrastructure, and amount of information in the Internet over the past few years. The International Telecommunication Union (ITU) estimates that the Internet has grown from about 4.4 million users in 1991 to 655 million in 2002. [1] Internet user population for 2004 is projected at 709.1 million (eMarketer) and 945 million (Computer Industry Almanac).
The Internet has become a powerful tool and enabler in various fields, including communication, hobbies, learning, commerce, governance, research, entertainment, agriculture, and the arts. It is the most pervasive medium worldwide, commanding the attention of anyone who wants to keep abreast of world developments.
Box 1: Your Computer to the Internet
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What is the difference between the Net and the Web?
[edit | edit source]The Internet (or Net) is a network of networks. It is made up of computers, cables, and other networking hardware. Different individuals and institutions have helped develop tools and protocols that use the Internet as a medium for information or data exchange.
The Internet encompasses data exchange facilities (computers, servers, hubs, switches, backbones, etc.) and protocols (HTTP, FTP, TCP/IP, WAP, etc.) and other applications (email, telnet, chat, instant messaging, streaming video, usenet, etc.).
The World Wide Web (or Web), on the other hand, is the most popular of all Internet applications. The Web provides users with the ability to access information and services while connected to the Internet. Web users may also publish information and offer services that can be accessed by anybody else in the Internet. The Web’s primary protocol, HyperText Transfer Protocol (HTTP), allows users to jump from one link to another. This is similar to reading many references and skipping from one topic to another instead of reading in a fixed sequence (for example, from page 1 to 100).
What is the most common way of connecting to the Internet?
[edit | edit source]Dialing from a computer via a modem and phone line is still the most common way of connecting to the Internet.
Different areas and telephone companies have different telephone facilities. The telephone equipment in a user’s vicinity and the equipment of the telephone company will determine the type of service that will be available to a user.
Public Switched Telephone Network (PSTN) refers to the telephone system based on copper wires carrying analog voice data. PSTN requires the user to have a modem to dial up to the ISP. It is also commonly known as Plain Old Telephone Service or POTS.
PSTN uses a circuit switched network to transmit continuous real-time data (e.g., voice). Live video is also transmitted better via a circuit switched network. Packet switched networks are used for data that do no need to be sent immediately or in real-time. Thus, email, the Web, chat and other Internet applications use packet switching.
Packet switching technology is continuously being improved. Eventually, packet switching networks will be able to transmit voice and video as efficiently as circuit switching networks.
Table 1: Comparison of Circuit Switched and Packet Switched Network
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What is DSL?
DSL (Digital Subscriber Line) is a form of high-speed Internet access over standard telephone lines. Unlike regular dial-up connection, which requires a modem, DSL provides a dedicated connection to the Internet and the PC is always connected to the ISP. Furthermore, DSL can handle a telephone call and Internet access at the same time.
There are three types of DSL, namely, Asymmetric DSL (ADSL), Symmetric DSL (SDSL) and ISDN DSL (IDSL). These types differ in the speeds of receiving and sending data.
DSL in general is more expensive than ordinary dial-up access. The advantage, of course, is a faster Internet connection.
What is ISDN?
Integrated Services Digital Network or ISDN is an international communications standard for sending voice, video and data over digital telephone lines. ISDN lines may be used to make regular calls to PSTN or DSL phone lines.
ISDN has two kinds of channels, which are like different lanes on a single highway. The B-channel can be used for Internet connections or voice calls. The D-channel is a signaling channel used by the ISDN network equipment. [3]
In addition, ISDN has two pre-defined configurations: Basic Rate Interface (BRI) and Primary Rate Interface (PRI). BRI uses two multimedia channels and one signaling channel within a single line. BRI is used primarily by small offices and home users to connect to the Internet. A PRI connection supports 23 (sometimes 30) multimedia channels and one signaling channel. It is used primarily by corporations and organizations with large communication requirements.
ISDN modems and lines are more expensive than standard dial-up, cable modems and DSL lines.
Can I get an Internet connection through my cable TV?
Cable television providers have started to deliver Internet access. In some cases, a single cable from the cable company can connect to both the television and the computer through a cable modem. The modem takes care of separating data for the TV and data for the computer. Whereas dial-up and DSL connections make a one-to-one connection to the Internet provider, cable modem users must share bandwidth with everyone else on the network. The more people online using the same pipeline at any moment, the slower the data transfer rate will be.
What is broadband?
[edit | edit source]Broadband, formed from the words broad and bandwidth, pertains to data carriers that have significantly wider bandwidth than the ordinary dial-up access of home-users. A wider bandwidth translates to a faster Internet connection. DSL, ISDN and Cable Internet are considered broadband connections to the Internet.
Having broadband is just like having a wider pipe to supply water to a household. Broadband allows Internet users to view Web pages more quickly, including multimedia files. Ordinarily, it takes several minutes for large images to be downloaded from the Internet using an ordinary dial-up. With broadband, a user will be able to download movies, audio and image archives. Users will be able to maximize video conferencing. They will also be able to make national and international phone calls using the Internet.
What are wireless technologies?
[edit | edit source]Wireless technologies refer to methods or devices that achieve data transfer without the use of wires connecting two devices. Essentially, wireless technologies are based on radio frequency waves just like a music radio or a two-way radio.
There are mobile wireless and fixed wireless configurations. The difference between them has to do with whether the devices are movable. Examples of mobile wireless devices are the mobile phone, personal digital assistant (PDA), laptop computer, digital camera, and audio player. A powerful quality of the mobile device is that the user can take it anywhere.
Fixed wireless, on the other hand, refers to wireless devices or systems that are situated in fixed locations such as an office or home. A wireless LAN (WLAN) using desktop computers is an example of a fixed wireless device. (See discussion on Wi-Fi.)
Satellite Internet access is also high-speed. Unlike the analog dial-up and the DSL, satellite access is available practically anywhere, even in remote areas without phone lines. Aside from the Internet, television channels and radio stations can be transmitted to a user’s satellite dish. For countries that do not have good telecommunications infrastructure, satellite technology is an option for Internet connectivity. However, considerable electric power is needed for wireless data transmissions using a satellite connection.
Figure 4: Table 2: Comparison of Local Loop Data Carriers
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Adapted from: “A Broadband Primer,” BusinessWeek online (October 8, 2001); available from http://www.businessweek.com/magazine/content/01_41/b3752049.htm; accessed 3 September 2002.
What is Bluetooth?
[edit | edit source]Bluetooth is a global standard for a short-range wireless connectivity that can establish links between mobile phones, PCs, laptops, PDAs, and digital cameras, among other devices. It enables a user to connect with a single or several devices at once. Because it is a global standard accepted by major telecommunication, software and networking companies, it is expected to become a widespread technology within a few years. This will allow “universal” and seamless data communication of various devices across different platforms and different hardware.
Bluetooth eliminates short data cables. For example, Bluetooth can replace the cable that connects a music player or mobile phone to a headset. It can also be used to replace the data cable used to synchronize PDAs with computers. Bluetooth focuses on applications where there is low power requirement and where data transfer rates are moderate.
What is Wi-Fi?
[edit | edit source]Wi-Fi, short for wireless fidelity, is a broadband wireless technology with a data transfer rate of more than 10 times that of Bluetooth. It is based on the IEEE 802.11b industry standard. Products certified as Wi-Fi by Wireless Ethernet Compatibility Alliance (WECA) are interoperable with each other even if they are from different manufacturers. A user with a Wi-Fi product can use any brand of access point with any other brand of client hardware that is built using the Wi-Fi standard.
Wi-Fi offers a 100-meter range and an 11-Mbps transmission rate. This makes it ideal for quick Internet access. Wi-Fi’s foremost use is to augment existing local area networks (LAN). Although Wi-Fi is not necessarily going to replace wired LANs, it makes a network more versatile in terms of expansion and can also increase users’ mobility.
What is the difference between Bluetooth and Wi-Fi?
[edit | edit source]Although Bluetooth and Wi-Fi operate in the same frequency of 2.4GHz, the two technologies have three main differences: range, data speed and power consumption.
It must be noted that Bluetooth and Wi-Fi operate in a portion of the ISM band commonly allocated to the industrial, scientific and medical fields. Worldwide, the ISM band is generally used free of charge and without license for non-commercial purposes.
Common appliances such as cordless phones and microwave ovens, as well as magnetic resonance instruments (MRIs) and medical equipment may interfere with devices using Bluetooth and Wi-Fi. [5] Technology is being improved so that interference between devices can be avoided.
The regulatory policies in the deployment of Bluetooth and Wi-Fi should also be carefully reviewed.
Table 3: Comparison of Bluetooth and WiFi
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Adapted from Michael Man, Bluetooth and WiFi (Socket Communications, March 2002); available from http://www.socketcom.com/pdf/TechBriefWireless.pdf; accessed 3 September 2002.
How do mobile wireless devices access the Internet?
[edit | edit source]There are a couple of ways to connect to the Internet via wireless devices.
WAP (Wireless Application Protocol) is a protocol that enables some mobile phones and PDAs to transfer data from the Internet. [6] To gain access to the Internet, a subscriber needs to connect to the cellular phone company’s gateway. The gateway connects to WAP servers that provide content. Content is written in wireless markup language (WML), a programming language designed for displaying information accessed via WAP. A WAP-enabled mobile phone has a micro-browser to view sites. Not all Web sites can be accessed using WAP. Content needs to be written in WML so that a WAP-enabled mobile phone can access the content. WML may also be embedded in Web sites so that portions of the Web site may be accessed using WAP.
General Packet Radio Service or GPRS is a technology that speeds up the data transmissions of WAP. [7] GPRS gives access to the Internet at speeds of 56 to 114kbit/s using packet switching. Its key feature is that a user is charged only for the packets of data that are transferred regardless of how much time it takes to transfer these data. Without GPRS, a user will most likely be charged on a per-minute basis re-gardless of the amount of data transmitted.
3G refers to the 3rd Generation Phone, which gives a user access to regular voice calls, short message service (SMS), email, Internet access and video. Some 3G phones have built-in video cameras that may be used to take digital photos or videos, which can be sent to other 3G phones. 3G boasts of transmission speeds reaching from 128kbit/s up to 2Mbit/s depending on whether the phone is at standstill or in a moving vehicle.
A mobile phone can also be used to connect a PDA or laptop computer to the Internet. The PDA or laptop is attached to the mobile phone and is the user’s primary visual interface to the Internet instead of the small screen of the mobile phone. Web-enabled mobile phones are increasingly able to access Web content that was originally designed for traditional PCs. In countries lacking general access to large screen computers, mobile Web-enabled devices are viable alternatives, giving more of the population access to vital knowledge resources. The W3C, responsible for Web technology, is paying particular attention to this new aspect of the Web and its effect in developing countries.
- Box 2. Applications of High-Speed Wireless Solutions for Developing Countries: Lessons Learned in Latvia and Moldova
Because of poor-quality telephone infrastructure, developing countries face the difficult task of connecting locations (located in the same area/city) with dedicated high-bandwidth needs (from 256 kbit/s to 4 Mbit/s). The Eastern European countries of Latvia and Moldova are examples of countries where poor telephone infrastructure has been overcome by providing high-speed wireless Internet links to universities, schools, and government agencies.
In Latvia in 1993, LATNET, the Latvian academic network, began experimenting with lowcost 2 Mbit/s wireless local area network (LAN) personal computer adapters for use in a citywide university network. Currently the LATNET wireless system in Riga is the most important part of the educational network, connecting more than 200 sites, including university departments, institutes, high schools, and government agencies.
The country of Moldova received its first dedicated Internet connection in 1996, when the capital Kishinev was connected to the Internet by a 256 K VSAT (very small aperture terminal) link to Norway. Virtually overnight, the city government-sponsored project was connecting schools, government agencies, and nonprofit, nongovernmental organizations with full-time, high-speed dedicated Internet links. Since then the wireless network in Moldova has expanded considerably through local efforts.
Source: Guntis Barzdins, John Tully and Arnis Riekstins, “Applications of High-Speed Wireless Solutions for Developing Countries: Lessons Learned in Latvia and Moldova,” INET 99 [home page online]; available from http://www.isoc.org/isoc/conferences/inet/99/proceedings/4d/4d_2.htm; accessed 3 September 2002.
What is convergence?
[edit | edit source]Convergence is the coming together of computers, communications networks, and broadcasting/television. More and more data are being stored in digital format and networks are becoming digital. Thus, in the near future there will be no need for separate TV and communications networks. TV shows will reach viewers via the telephone network just as easily as when using a TV broadcasting network. A more formal and comprehensive definition of convergence is “the progressive integration of the value chain of the information and content industries-telecommunications, posts, multimedia, electronic commerce, broadcasting, information technology, and publishing industries-into a single value chain based on the common use and distribution of digital technology.” [8]
Convergence can be classified into three types:
1. Convergence of technologies - a common platform to deliver voice, data and video services
2. Convergence of services - delivery of multiple services to end users over the same medium/network
3. Regulatory convergence - establishing a single Regulatory Authority (RA) with the blurring of the regulatory boundaries for telecommunication, information technology and broadcasting
Why and how is convergence essential?
[edit | edit source]Convergence revolutionizes two things: the communications infrastructure and the way in which people communicate with one another. Communication in this new technological milieu will be more efficient and more economical as the need to set up separate networks for telephone services, television broadcast, cable television, and Internet access will be eliminated. From the standpoint of a consumer, having only one information provider will mean cheaper communication costs.
Moreover, the principle of universal access can be made more achievable with convergence. The present scenario shows that the high costs of installing landlines in sparsely populated rural areas prevent telecommunications companies from installing telephones in these areas. The private sector can be motivated to install landlines in rural areas if revenues from these landlines will not be limited to local and long distance telephone charges, but will also include cable TV and Internet charges.