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Linking rural health facility to the internet using packet radio in
developing countries(OAUNet a case study)
by
O.O. Abiona & O.A. Adewara
Obafemi Awolowo University, Ile-Ife
Nigeria.
We shall consider
What is packet radioChoice of packet over other modeComponent of a packet stationDistance limitation of packet radioChannel SharingWhat is AX.25The OAUNet
Continue…..
Problems in rural communityServices for rural connectivityConclusion
What is packet radio
A particular digital mode of amateur radio communication which corresponds to computer telecommunication.
The telephone modem is replaced by a “magic” box called a Terminal Node Controller (TNC)
Telephone is replaced by an amateur radio transceiver.
Continue…...
The phone system is replaced by the “free” amateur radio waves.
Packet radio takes any data stream sent from a computer and sends that via radio to another amateur radio station similarly equipped.
Why packet over other modes
TransparencyError correctionAutomatic control.
Components of a packet station
Terminal Node Controller (TNC)
A modemA computer processorAssociated circuitry to convert
communication b/w your computer(RS-232) and the packet radio protocol in use.
Function of a TNC
Assembles a packet from data received from the computer.
Computes an error check for the packet. Modulates it into audio frequencies.Transmit the packet over the connected
radio.It also reverses the process
Computer or Terminal
A computer running terminal emulation program or a dumb terminal.
E.g hyperterminal, procomm+, X-Talk, Pacterm
A Radio
For 1200/2400bps UHF/VHF packet.Commonly available narrow band FM voice
radio.For HF packet 300bps data is used over
single side band modulation.For high speed packet (starting at 9600bps)
special radio or modified FM radio are used.
Distance limitation of packet radio
It is used at higher radio frequencies (VHF), the range of the transmission is some what limited.
Limited to unobstructed “line-of-sight”For two meter packet (144-148MHZ) the
range could be 10 - 100miles
Channel Sharing
Can support multiple conversation on the same frequency at the same time.
Multiple conversation are possible in a managed time shared fashion.
It uses the AX.25 to accomplish this shared channel.
What is AX.25
Is the communication protocol used for packet radio.
Is based on the wired network protocol X.25.
The OAUNet
Obafemi Awolowo University Network
Obafemi Awolowo University
Academic Network Project
OAUNET - Current Design
Present load estimates
Overview of Network
INFRASTRUCTURAL PROBLEMS AND SOLUTIONS
Problem:Analogue exchange necessitating Solution: Store and forward / VSAT
Internet connectivity since January 1999.
Problem: Unreliable Power Supply
Solution: Back-up-- UPS & Generators
Services Provided
Basic E-mailWeb access
File Transfer
Remote access
OAUNET - Main Network Diagram
MainHUB
sc tech cs
usb chs agric
NC
FirstGeneration
SecondGeneration
ThirdGeneration
Keysc - sciencestech - Technologycs - Computer Scienceusb - Secretariatchs - Health ScienceAgric- AgricultureNC - NACTEMTH - OAU Teaching hospital
TH
WaveLan2Mbps
VSAT Earth Station
64 Kbps
Dial upMODEM14.4 Kbps
*****Packet and HF radio links to rural Health establishments in the area
Breezecom Lan2-3 (FHSS)Mbps
CERDBreezecom LAN
2-3 Mbps(FHSS)
Main HUB or network
FirewallProxy
Mail Server
Comm.Server
Backup Server
InterSubnetRouter
WLAN Antenna
WEB Server
Terminal Equipment
CISCOrouter
10 base 2 Ethernet Backbone (Server Bus)
Pentium II PCs
Architecture of Most SubnetsUsing AT&T Wireless
HUBOne or more client computersRunning Windows or
Linux +GUIProvide Print services,and telnet. Clients are
Auto- configured through DHCP
Ethernet
915 MHzAntenna
2 Mbps link to Main network
Sciences Subnet
HUBOne or more client computers
Running Windows or Linux + KDE
Provide Print services, and telnet clients
Auto- configured through DHCP Located in Public access rooms and
Private offices and Laboratories
915 MHzAntenna
Server forPhysics Dept. &Electronics Dept.
WavePointRadio
2 Mbps link to Main network
Computer Science SubnetCS Server
Floor 3
Floor 2
Floor 1
Ground Floor HUB
HUB
HUB
HUB
HUB
Dean of Faulty & other Faculty staff
Head of Dept. & other Senior Dept. staff
Other Dept. Staff & Laboratories
Machines in public rooms &
access areas
Linux Router For MIS, Computer Centre
& URC
10 Mbps Link to Main network
To MIS
To URC
To Computer Centre & IBM AS 400
Main Frame
Library Subnet
915 MHzAntenna
WavePoint
Linux RouterWith Netware
Emulation
Novell Netware 4Server with TCP/IP
Mecury MAIL Server
Windows 95 Netware clientsand other Library catalog system
Pegasus Mail Clients
2 Mbps link to Main network
CONTENTS FOR THE INTERNET
Observatories/Data banks:
Science Database, Water Resources and Rural Development
National Databank, Raw Materials Research Council Databank
Growth of users
0
200
400
600
800
1000
1200
1400
1600
1800Ju
l-96
Oct
-96
Jan-
97
Apr
-97
Jul-
97
Oct
-97
Jan-
98
Apr
-98
Jul-
98
Oct
-98
Jan-
99
Apr
-99
Jul-
99
Oct
-99
Jan-
00
Apr
-00
Jul-
00
Oct
-00
No
of U
sers
Date
Monthly Growth of Users
0
20
40
60
80
100
120
Jun-96
Jul-96
Aug-96
Sep-96
Oct-96
Nov-96
Dec-96
Jan-97
Feb-97
Mar-97
Apr-97
May-97
Jun-97
Jul-97
Aug-97
Month
No
. of
us
ers
Tech
EDM
HS
Education
Pharmacy
Agric
Science
Arts
Admin
Soc Sci
Law
Others
Percentage Level of Awareness
Level of awareness on the use e-mail on faculty by faculty basis
0,00%
10,00%
20,00%
30,00%
40,00%
50,00%
60,00%
70,00%
EDM Pharmacy Technology Law Science Arts
Faculty
Pe
rce
nta
ge
of
e-m
ail u
se
rs
1
2
3
1.e-mail 96%2. ftp 3.5%3.www 0.5%
Type of services provided as at 1996
Type of services provided as at 2000
50%
8%
42%1
2
3
Type of services provided as at 2000
1. e-mail = 50%2. ftp = 8%3 .www =42%
Trafic Distribution
tech
edm
health
educ
pharm
agric
science
arts
admin
social
law
others
Other Services ProvidedConsultancy services to Educational Institutions. This
entails:
-Network site survey
-Structured Cabling
-Computer hardware Installations and Repairs
-Web enabling services
-Internet Services (system configuration)
Federal University of Technology, Akure (FUTA) ,University of Lagos, Yaba, Lagos State University, Badagry, University of Agriculture, Abeokuta,University of
Ilorin,Dept. of Physics, University of Ibadan and the College of Education, Ikere-Ekiti
Antenna types (1)
SPECIFICATIONS
Antenna:
Antenna Gain* 8 dBi
Frequency Range 2.4 to 2.5 GHz
Impedance 50 Ohms
Polarization Vertical
Dimensions 17" length; 43 cm
Weight .45 lbs; 205 g
SPECIFICATIONS
Antenna:
Antenna Gain* 24 dBi
Frequency Range 2.4 to 2.5 GHz
Impedance 50 Ohms
Polarization Vertical or horizontal
Dimensions 24" x 36" x 15"; 610 x 915 x 381mm
Weight 5.4 lbs; 2.43 kg
915 MHz Antenna types (2)
Problems of rural Community
They lack well developed telecommunication infrastructure.
Lack of constant electricity supply.Lack of good road network.Lack of portable water supplyetc...
Services for rural Connectivity
E-mail services.Ftp. (minimal)Www (minimal or hardly used).
The established link
TNC
Radio
OAUNet
Radio
TNC
Cost estimation for high speed Packet radio
Link. S/N Description Amount
1. 2 Nos of TNC @ $200.00 $400.00
2. 2 Nos of Radio @ $100.00 $200.00
3. 2 Nos of Antenna @ $50.00 $100.00
4. Accessories $ 50.00
Total $750.00
Low Cost Implimentation
S/N Description Amount
1. 2 Nos of TNC @ $00.00 $00.00
2. 2 Nos of Radio @ $100.00 $200.00
3. 2 Nos of Antenna @ $50.00 $100.00
4. Accessories $ 50.00
Total $350.00
ConclusionIn view of the problems facing the rural
community and developing nations in general, coupled with the problem of funds to acquire high speed connectivity, Packet radio could be a way out for developing countries to spread internet connectivity to rural communities.
We want to thank ICTP for making this possible for OAU, Ife and Nigerian Universities at large.
END
Thank You.