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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 radio Choice of packet over other mode
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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 radio • Choice of packet over other mode • Component of a packet station • Distance limitation of packet radio • Channel Sharing • What is AX.25 • The OAUNet
Continue….. • Problems in rural community • Services for rural connectivity • Conclusion
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 • Transparency • Error correction • Automatic control.
Terminal Node Controller (TNC) • A modem • A computer processor • Associated 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.
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-mail Web access File Transfer Remote access
VSAT Earth Station 64 Kbps WaveLan 2Mbps Main HUB Dial up MODEM 14.4 Kbps OAUNET - Main Network Diagram Key sc - sciences tech - Technology cs - Computer Science usb - Secretariat chs - Health Science Agric- Agriculture NC - NACTEM TH - OAU Teaching hospital First Generation sc tech cs Second Generation chs agric usb CERD Breezecom LAN 2-3 Mbps (FHSS) Third Generation NC Breezecom Lan 2-3 (FHSS)Mbps *****Packet and HF radio links to rural Health establishments in the area TH
WLAN Antenna Inter Subnet Router Main HUB or network Mail Server WEB Server Terminal Equipment Backup Server Comm. Server Proxy Firewall CISCO router Pentium II PCs 10 base 2 Ethernet Backbone (Server Bus)
2 Mbps link to Main network 915 MHz Antenna Architecture of Most SubnetsUsing AT&T Wireless HUB One or more client computers Running Windows or Linux +GUI Provide Print services, and telnet. Clients are Auto- configured through DHCP Ethernet
915 MHz Antenna 2 Mbps link to Main network Sciences Subnet WavePoint Radio HUB Server for Physics Dept. & Electronics Dept. One 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
10 Mbps Link to Main network CS Server Dean of Faulty & other Faculty staff Floor 3 HUB Head of Dept. & other Senior Dept. staff Floor 2 HUB Other Dept. Staff & Laboratories Floor 1 HUB Ground Floor HUB To URC To MIS Machines in public rooms & access areas HUB Linux Router For MIS, Computer Centre & URC To Computer Centre & IBM AS 400 Main Frame Computer Science Subnet
915 MHz Antenna 2 Mbps link to Main network Library Subnet WavePoint Windows 95 Netware clients and other Library catalog system Pegasus Mail Clients Linux Router With Netware Emulation Novell Netware 4 Server with TCP/IP Mecury MAIL Server
CONTENTS FOR THE INTERNET Observatories/Data banks: Science Database, Water Resources and Rural Development National Databank, Raw Materials Research Council Databank
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Other Services Provided Consultancy 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* 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 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
Problems of rural Community • They lack well developed telecommunication infrastructure. • Lack of constant electricity supply. • Lack of good road network. • Lack of portable water supply • etc...
Services for rural Connectivity • E-mail services. • Ftp. (minimal) • Www (minimal or hardly used).
The established link OAUNet Radio Radio TNC 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
Conclusion • In 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.