Connectivity Providers Database

From: Khursh Ahmed <ahmed@FHS.CSU.MCMASTER.CA> Date: Wed, 28 Jul 1993 14:04:45 +0500 I mentioned a very successful installation of a local Packet Radio Network in Indonesia recently (I also mentioned that it does not YET connect to Internet). I have had a number of messages for further information. I decided to type the original article from the newsletter; it is not very technical but provides an overview of the set up. Further information *may* be available from the author. =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--= From the newsletter "PRIORITAS KESEHATAN - Health Priorities", March 1991. Published by Fakultas Kedokteran, Universitas Gadjah Mada, Yogyakarta, Indonesia. Teknologi Telekomunikasi - The Technology of Telecommunications by Tri Kuntoro Priyambodo. The Need for Communication The ability to control information in this era of information globalization and revolution is the key to successful strategy identification and decision making. Therefore, data and information management endeavors in any activity will always gain priority consideration. The need for a functional information system becomes even more obvious in an undertaking that attempts to monitor and control the health of communities, such as in the Early Warning System of the Department of Health. The Gadjah Mada and McMaster Universities took the initiative to lay the groundwork for an electronic health data communication network experiment in Central Java, Indonesia. Basically the network consists of a system of computers interconnected by radios. Each unit can communicate with the other units. One computer assumes the role of center or host and the others act as terminals or nodes. The computers of a network can be interconnected by direct cables (if the distances are small), telephones or radios. In the last two ASCII or binary characters are converted into sounds of a certain frequency before being sent through telephone lines or radio-transmitters. Radios were chosen for this experiment because they can cover very large areas, especially isolated areas which do not have automatic telephones. At the moment 1 center and 7 nodes were set up (see Figure 1). Each node consists of 1 computer and 1 communication unit. A 40 mega byte hard disk is installed in every computer for storing data and programs. A transmitter, a receiver and an antenna make up the communication unit. The computer is connected to the communication unit by a modem, which converts computer characters (binary) to sound when sending messages and transforms sound to computer characters when receiving information. Figure 1 - Health Information Electronic Telecommunication Network (Please note, all stations are inter-connected, shown by connecting lines in the original diagram) Provincial Health Office (Central Java) District Sub-district Health Office Health Centre (Mageland) (Delanggu) Computer Centre Gadjah Mada University GMU CEBU District GMU Health Office (Wonogiri) GOME Medical Records GMU Sardjito Teaching Hospital The host and nodes possess similar hardware. However, because the host must serve all other nodes some of its characteristics need special consideration. Among others, the host must have the capacity to retain data from all nodes that are meant for collective use. Therefore, a sizable hard disk is required. At the moment a 300 Mega bytes disk is in place. Furthermore, its communication gear must have the power to adequately reach all nodes. This requires a transmitter that has the ability to reach distant places and to distribute messages equally to all directions. Nodes can be interconnected directly, using other nodes as digital repeaters, or indirectly, as an extension of other terminal nodes. The first method is applied if there are no communication obstacles between the two communicating nodes. The second approach is exercised if the connection between the two nodes is unsatisfactory. The host is often used as repeater due to its equal transmission to all directions. Every node is furnished with special software to facilitate the interconnections between two nodes. Through this software users of two nodes can communicate as well as exchange data. However, for data exchange operators need to be present at the nodes because the sending and receiving of data are accomplished manually. A preferable method of communication is via the host, which is equipped with a software specifically designed for serving the nodes. The sending of data can be performed without the assistance of other users. Development of the Present Network The present system can be further improved. Among others, by utilizing the host not only as a data depository but also as a data processing center. This will save time because data is transferred only in one direction, i.e., from node to host. An additional advantage is that only one high capacity computer is required (i.e. the host) for high speed information processing. This means that the large software reside only in the host. In other words, each node simply needs a program for sending data to and receiving processed data from the host. Another more important advantage of this new communication method is there will be no more data duplication. In addition, the consistency of data will always be maintained. Obviously, the shortcoming of this approach lies in the very fact that the whole system is overly dependent on the host. A breakdown of the host any one time may paralyze the whole system. Summing up... The health information electronic telecommunication network is a reasonably reliable infrastructure for a health information system. This network is very useful for communication of distant places that do not have automatic telephones. (Mr. Tri Kuntoro Priyambodo, MSc is a staff member of the Computer Centre, Gadjah Mada University. Another person who is very knowledgeable about the system, and a ham radio operator, is Dr. Winardi, Dept. of Obstetrics/Gynecology, GMU). While Mr. Priyambodo and Dr. Winardi do not have access to Internet, you may be able to send messages through soenarto@cosy.uoguelph.ca with a request to pass the message on. ********************************************************************* Khursh Ahmed Ph.D. Internet: ahmed@fhs.mcmaster.ca Faculty of Health Sciences, HSC-2D5 Voice: (416) 525-9140 x2443 McMaster University, Fax: (416) 521-0048 Hamilton ON, L8N 3Z5, Canada