ICT in Education Toolkit Version 2.0a
September 2006
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Tool 3.1: Infrastructure
  OVERVIEW
1 Electric Power
Regional Level
Institutional Level
2 Audio/Radio
Infrastructure Needs
Infrastructure Plans
3 Video/Television
Infrastructure Needs
Infrastructure Plans
4 Internet/Connectivity
Infrastructure Needs
Infrastructure Plans
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Toolbox 3:
Planning for Physical and Human Requirements
3.1 Infrastructure
3.2 Hardware
3.3 Personnel Training
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Alternative Source of Energy

Broadcast Radio verus Audio Recordings

Broadcast Television versus Video Recordings

Connectivity Options


 

Alternative Source of Energy

There are alternative sources of energies that can be used in case electricity is not available or if the electric grid is insufficient or unreliable. Energy alternates that have been experimented with in many countries include:

Solar Energy: Photovoltaic (PV) solar cells consist of semi conducting material that absorbs the sunlight. The solar energy knocks electrons loose from their atoms, allowing the electrons to flow through the material to produce electricity. PV cells are typically combined into modules that hold about 40 cells. About 10 of these modules are mounted in PV arrays. PV arrays can be used to generate electricity for a single building or, in large numbers, for a power plant. A power plant can also use a concentrating solar power system, which uses the sun's heat to generate electricity. The sunlight is collected and focused with mirrors to create a high-intensity heat source. This heat source produces steam or mechanical power to run a generator that creates electricity. For an example see Resource 3.1.1.

Wind Power: Wind power has been in use for hundreds of years as a source of energy for pumping water and grinding grain. More recently, wind turbines are utilizing the wind's energy to generate electricity. Like the windmills, the wind turbines are mounted on towers that take advantage of the faster and less turbulent wind. The turbines have usually two or three blades mounted on a shaft to form a rotor. The wind causes the rotor to spin like a propeller and the turning shaft spins a generator to make electricity. Some turbines are connected to a utility power grid or solar cell system. A turbine usually produces 50 to 300 kilowatts of electricity (enough to light up 3,000 100 W light bulbs). For utility-scale, a large number of wind turbines are built close together to form a wind plant. For an example see Resource 3.1.2

Pedal Power: An electricity generator can be run by a pedal mechanism similar to that of a bicycle. Fifteen minutes of pedaling can run one 11 W compact fluorescent light (CFL) bulb for an hour. A radio, tape recorder or loudspeaker use only about 1-5 Watts. For an example see Resource 3.1.3.

Generator Sets. Small-scale electricity generator sets commonly known as gensets are among the most technologically and commercially mature options for distributed energy generation. Generator sets have relatively low capital costs but high running costs due to the need to purchase fuel and provide regular maintenance. If routine maintenance tasks are not carried out regularly, the genset may break down before its time.

 

For generator sets with a capacity of less than 3 kW, gasoline and diesel are popular fuels. Genset engines may also use other fuels, such as propane, kerosene, biogas, biofuels or fossil/biofuel mixtures.

 

Source of excerpt and for further information: 

http://www.dot-com-alliance.org/POWERING_ICT/  

 

To learn more about energy options go to:

http://www.dot-com-alliance.org/POWERING_ICT/pub/Energy_Options.htm


Broadcast Radio verus Audio Recordings

Broadcast Radio
Strengths:

Radio programs can be listened to anywhere; there is no need for an institutional setting
With added users there are no additional development costs or cost of tapes/CDs
Programs can be revised continuously and centrally
Radio can offer time-sensitive programs such as educational news, directives, pedagogical guidelines, etc.
Radio receivers are available anywhere, are versatile, and inexpensive; there are also receivers that do not depend on current or battery electricity ( see Resource 2.7.1)

Drawbacks:
Radio programs follow a prearranged schedule; this requires coordination with users (institutions and learners).
Radio programs require an "external" transmission infrastructure
There may be a considerable cost for air time.

Audio Recordings

Strengths:
Can be listened to anytime; no need for special scheduling
Can be stopped at any point for questions or intervening activities
Do not require a transmission infrastructure or acquisition of air time

Drawbacks:
Audio recordings need playback instruments (cassette or CD player) that are more expensive than radio receivers.
Use of audio recording usually needs an institutional setting
With added users there is a need for additional tapes/CDs
Centrally revised recordings require new tapes/CDs
Audio recordings are not well suited for time-sensitive materials


Broadcast Television versus Video Recordings

Broadcast Television

Strengths:

  • TV programs can be listened to anywhere; there is no need for an institutional setting
  • With added users there are no additional development costs or cost of tapes/DVDs
  • Programs can be revised continuously and centrally
  • TV can offer time-sensitive programs such as educational news, directives, pedagogical guidelines, etc.
  • TV sets are widely available in homes and workplace; where electric power is a problem, TV sets use less energy than added VCRs and DVD players.

Drawbacks:

  • TV programs follow a prearranged schedule; this requires coordination with users (institutions and learners).
  • TV programs require an "external" transmission infrastructure
  • There may be a considerable cost for air time.

Video Recordings

Strengths:

  • Can be viewed anytime; no need for special scheduling
  • Can be stopped at any point for questions or intervening activities
  • Do not require a transmission infrastructure or acquisition of air time

Drawbacks:

  • Video recordings need playback instruments (VCR or DVD player) that are needed in addition to the TV sets. Even when computers are provided and are to be used for viewing DVDs, there is a need to make extra investment in such computers.
  • Since video playing instruments are not readily available on an individual basis, use of video recording usually needs an institutional setting
  • With added users there is a need for additional tapes/DVDs
  • Centrally revised recordings require new tapes/DVDs
  • Video recordings are not well suited for time-sensitive materials


Connectivity Options

Technology

Use

Comments

Terrestrial Wireless

Cellular

If no fixed lines are available, but there is cellular service, a cell phone with a cellular modem can be used to allow access to the Internet.

Costly

Bandwidth is limited

More practical for e-mail than for surfing the Web

Wireless local loop

Rural schools can connect to the nearest telephone network via a wireless link.

Faster extension and lower ratio of fixed to incremental costs than wiring

Point-to-Point Wireless Systems

Point-to-point fixed wireless, such as microwave systems, can provide high-speed Internet access by connecting to an ISP's point of presence (POP). [2]

May be the least expensive means of getting high-speed Internet access when wireline services are not available

Wireless Access Protocol:

This wireless protocol has been developed to make it possible to transmit Web pages and other data to cellular phones. It can be adapted for wireless services in developing countries so that Internet information can be transmitted to low-bandwidth wireless systems.

Limited web content accessible through this system

Third Generation Mobile Services

Third-generation mobile networks are beginning to be introduced in some industrialized countries, and eventually may be made widely available in developing regions. They offer greatly increased bandwidth than existing mobile networks, with the possibility of Internet access to handheld devices such as portable phones, personal digital assistants, and small personal computers.

Capital cost of upgrading existing networks is high

Price of access for Internet applications may be greater than for other options.

Satellite Technologies

Very small aperture terminals (VSATS)

Small satellite earth stations operating with geosynchronous satellites can be used for interactive voice and data as well as for broadcast reception. [3](VSATs for television reception (known as TVRO-television-receive only) deliver broadcasting signals to viewers.)

n/a

Internet via satellite

Internet gateways can be accessed via geostationary satellites. For example, MagicNet, an ISP in Mongolia, and some African ISPs access the Internet in the United States via the PanAmSat global satellite system, and residents of the Canadian Arctic use Canada's Anik satellite system, while Alaskan villagers use U.S. domestic satellites.

Costly

Not optimized for Internet use

High-speed downlink

A system designed by Hughes, known as DirecPC, uses a satellite to deliver high-bandwidth Internet content downstream to a VSAT from an ISP. Upstream connectivity is provided over existing phone lines. This approach is designed for rural areas with telephone service, but where bandwidth is very limited.

n/a

Interactive access via VSAT

Several companies now offer fully interactive access to the Internet via satellite; examples include Gilat, Hughes Gateway, and Tachyon. The systems could be a solution for schools with no other communication options. For example, schools in Alaska and the Canadian Arctic access the Internet via satellite.

Costly but price of Internet access is likely to decline as new protocols are developed to make more efficient use of bandwidth

Data broadcasting by satellite

Geosynchronous satellites designed for interactive voice and data can be used for data broadcasting as well. For example, the WorldSpace satellite system delivers digital audio directly to small radios. In addition, it can be used to deliver Internet content; schools or telecenters can identify which Websites they want to view regularly, and WorldSpace broadcasts the data for reception via an addressable modem attached to the radio.

n/a

Global mobile personal communications systems

Using low earth orbiting satellites, these systems provide voice and low-speed (typically 2400 to 9600 bps) data virtually anywhere, using handheld transceivers.

Still very costly

Limited bandwidth

Store-and-forward messaging

Volunteers in Technical Assistance (VITA) has developed a satellite-based system, called VITAsat, capable of delivering sustainable, low-cost communications and information services to remote communities. The system uses simple, reliable, store-and-forward e-mail messages relayed to the Internet via low earth orbiting satellites. Using compression technology and software that allows access to Web pages using e-mail, VITAsat can make the Internet accessible virtually anywhere. VITA's two current satellite system have the capacity to serve about 2,500 remote rural terminals that could be installed in schools, clinics, community centers, and NGOs.

n/a

Bandwidth on demand

Future satellite systems are being planned to provide bandwidth on demand. Constellations of low earth orbiting satellites such as Teledesic and new generations of geosynchronous satellites such as Loral's Cyberstar and Hughes's Spaceway will be designed to offer bandwidth on demand for Internet access, videoconferencing and distance education.

n/a

Wireline Technologies

Dial-up Connection

The simplest and lowest-cost connection to the Internet is through dial-up access using a single standard phone line. A dial-up connection can provide Internet access to a single computer or, by using software on a server, networked computers can share this single connection. However, with a shared connection, access can become very slow, since the total available bandwidth is divided among all the computers sharing the same Internet connection. If two or three phone lines are available, these lines can be combined using an analog router to enable multiple phone line access to an ISP, thus increasing available bandwidth.

n/a

Dedicated Connection

Schools can get faster and more reliable Internet access by using permanent "dedicated" high-speed connections where they are available and affordable. A variety of dedicated high-bandwidth options may be available to schools, including integrated services digital network (ISDN) or digital subscriber line (DSL).

n/a

Cable modems

Some cable television systems can also be used for high-speed Internet access via cable modems. Like DSL, cable offers much higher bandwidth than dial-up telephone lines.

High volume of users may result in congestion of a shared cable network,

Older networks may not be converted easily for two-way connectivity

Optical fiber

Telephone companies upgrading their networks may install optical fiber for institutional customers such as hospitals, schools, and businesses. The advantage of fiber is its enormous bandwidth, which can be used for high-speed Internet accessing or other services such as videoconferencing.

Price of access may be prohibitive. Some schools have managed to gain free or heavily discounted access to so-called "dark fiber," excess capacity that has been installed but is not yet in use.

Hybrid fiber/coax

A combination of optical fiber and coaxial cable can provide broadband services such as TV and high-speed Internet access as well as telephony; this combination is cheaper than installing fiber all the way to the customer premises. Unlike most cable systems, this hybrid allows two-way communication. The fiber runs from a central telephone switch to a neighborhood node; coaxial cable links the node to the end user such as a school. Developing countries with such projects include Chile, China, India, and Malaysia

n/a
1
Excerpted from Eric Rusten and Heather Hudson. 2002). "Infrastructure: Hardware, Networking, and Connectivity." In Wadi D. Haddad and Alexandra Draxler (Eds.) Technologies for Education: Potential, Parameters, and Prospects. Paris: UNESCO, and Washington, DC: Academy for Educational Development
2
A narrowband radio system may be used to transmit and receive user information on a specific radio frequency. See Resource 3.1.4
3
See Resource 3.1.4

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