    UDT Series on Data Communication Technologies and Standards for Libraries Packet Radio: Applications for Libraries in Developing Countries (1993)5. PACKET RADIO PROJECTSWhile very few projects have been implemented that specifically use packet radio technology for library applications in developing countries, a wide array of packet radio networks have been developed for other purposes. In the industrialized world, packet radio networks have been created for experimentation with protocols and hardware, by amateur packet radio enthusiasts, and for investigating its utility for library applications. In developing countries, packet radio networks have been set up to support many different types of development activities, such as to disseminate health information. The present chapter briefly describes some of these projects.5.1 General packet radio network projects5.1.1 The ALOHA ProjectDuring the early 1970's, the ALOHA project at the University of Hawaii demonstrated the feasibility of using packet broadcasting in a single-hop system (see Abramson, 1970; and Abramson, et al, 1970). This work led to the development of a multihop multiple access packet radio network (PRNET) under the sponsorship of the Advanced Research Projects Agency (ARPA) (see Jubin and Tornow, 1987).5.1.1.1 PRNETThe PRNET, or Experimental Packet Radio Network, project was proposed by SRI International of Menlo Park and funded by the Defense Advanced Research Projects Agency (DARPA) starting in 1979 and running for four and a half years. Participants from academia and industry were organized in the Packet Radio Working Group (PRWG) and lead by an implementor's group (IG) composed of representatives from BBN, Rockwell, SRI and DARPA.The PRNET was located in the San Francisco Bay Area. It provided a testbed for development of packet radio protocols and technology. It consisted of several base stations which communicated with mobile vans.
The network implemented the TCP/IP suite of protocols which were developed in part in order to connect PRNET hosts to the ARPANET (Quarterman, 1990).
The modem used for encoding data into radio signals is the TNC. With the use of several TNCs on a single frequency, the network behaves as a broadcast network, much like that of Ethernet. A package called KA9Q has been developed specifically for amateur packet radio; it uses the internet protocol (IP) (and related protocols ICMP, TCP, UDP, TELNET, FTP and SMTP) over AX.25 with the internet address resolution protocol (ARP) for address mapping. KA9Q also supports the serial line internet protocol (SLIP).
Amateur packet radio is very attractive because of its low cost. The KA9Q package runs on IBM PC compatible machines and is free for noncommercial use. It has also been ported to many other computer environments. Ham outfits are also available that operate at speeds as high as 56 Kbps.
The network will carry commercial information which is in violation of amateur radio regulations of telecommunications jurisdictions of most western countries (e.g., the FCC in the U.S. and the CRTC in Canada). Thus, for this network, the radio amateurs have agreed to allow others to make use of their technology on condition that their presently allocates frequencies are not used and that the WARC (the commission that allocated the electromagnetic frequency spectrum worldwide) allocate them some extra room in the spectrum and be more positive to their experimental efforts (Shacham and Westcott, 1987).
The technical configuration of the PRIE consisted of MacIntosh computers, two-watt radios and omni-directional antennae at the two packet radio sites, with the addition of a Kinetics Fastpath gateway to interface between the Ethernet at the Hungarian Academy and the LocalTalk network required by the MacIntosh computers.
While the project was successful in creating a PRIE, the ground links through the Moscow hub was too slow for effective realtime use (Brownrigg, 1993).
Beginning in 1986, one of the earliest packet radio projects supporting library applications was the University of California Division of Library Automation's (DLA) research and development project to create a prototype wide-area packet radio network in northern California. Coverage of the initial network encompassed the area from Berkeley to Sacramento. The network was to operate at data rates on the order of 200 Kbps and will run the TCP/IP suite of protocols. The project was abandoned, however, due to: 1) problems obtained FCC frequency allocations; 2) diminished cost effectiveness of packet radio links compared with rapidly dropping common carrier costs; and 3) problems at the time of scaling up to sufficiently high bandwidths (Lynch, 1993). For a detailed description of the system design and the design process, see reference (Lynch and Brownrigg), 1987:259 San Diego Packet Radio Internet Extension (PRIE) The culmination of ten years of work beginning with the DLA experimental network outlined above is the San Diego Packet Radio Internet Extension (PRIE). The project involves the creation of a packet radio LAN connecting the San Diego Public Library (plus one SDPL branch), the San Diego State University Library, and the San Diego Zoo Library (Rogers, 1992). New U.S. Federal regulations and advances in packet radio technology have finally solved the problems that plagued the project for its 10 year history. The Memex Research Institute, with funding and equipment from the Council of Library Resources, Apple Computers, and Tetherless Access Ltd, is developing the San Diego PRIE. Begun in August 1991 and yet to be completed, the goals of the project are to (Hendricks and Brownrigg, 1992):
Configuration of the packet radio network will include both low-speed and high-speed links. The low speed links will be used to provide experience with the system, later to be replaced by the high-speed links. Ultimately, the investigators hope to establish libraries as another institutional tier in the Internet using packet radio (Hendricks and Brownrigg, 1992). Because libraries have severely limited funds, and packet radio uses "free" radio spectrum and low-cost equipment, packet radio offers an affordable alternative to common telecommunications carriers (Hendricks and Brownrigg, 1992).
Memex is planning to develop a 600 node network in the San Francisco Bay area, Fully 100 of these nodes will be libraries, if funding is found (Rogers, 1992).
Central to VITA's activities is the use of satellites and packet radio technology to support communication and information exchange in developing countries. VITA's communications program consists of three phases:
Phase II. The next phase of VITA's satellite communications project, from 1989 to 1993, was to design and construct a prototype digital communications devise that was integrated into UoSAT-3 (the same satellite used in HealthNet work). Called PACSAT Communications Experiment, the project will provide an opportunity to evaluate the technology for Phase III. Phase III. The final phase of VITA's program will be to design, construct, and launch its own LEO satellites, with the first scheduled for launch in 1993. When operational, the satellites will support a 1000 ground station network.
VITA has instigated many projects using space-based and terrestrial packet radio technology, some of which are described below.
Republic of Djibouti The National Institute of Higher Scientific and Technology Research (ISERST) in Djibouti has, with the assistance of VITA, installed a ground station to communicate with VITA's PACSAT. ISERST's role is to "encourage and assist applied research in areas that will improve the economy of the country as well as the standard of living of the Djibouti people [and to] introduce new technologies and promote their use" (Dirieh, 1992:71). ISERST was authorized in 1991 to install a ground station to communicate with the UoSAT-3 satellite, enabling it to communicate with other PACSAT and SatelLife stations throughout the world. ISERST's main goals in establishing the station was to "assist governmental and nongovernmental organizations with the exchange of technical information relating to health, energy, education, environment and humanitarian activities where communications systems are inadequate" (Dirieh, 1992:72). ISERST identifies training of packet radio operators to be the main challenge in sustaining the packet radio link. Sierra Leone PLAN International, a non-profit international development agency that aids needy children, has worked with VITA to establish a PACSAT radio ground station to overcome poor communications (Sandi, 1992). The telephone system in Freetown, the capital, has been described as erratic at best (Rosenburg and Garriott, 1992). After numerous problems and visits by VITA personnel (described in Rosenburg and Garriott, 1992), the groundstation became operational. PLAN staff in Freetown use the link to communicate with and send reports to the PLAN International Headquarters in the U.S. and the Regional Office in Dakar, Senegal. Secondary terrestrial packet radio stations are used to communicate with PLAN Field Offices approximately 200 kilometers from Freetown (Sandi, 1992). Tanzania The University of Southampton in the UK and the University Dar es Salamm in Tanzania have established a link through PACSAT to facilitate collaboration, experimentation and information exchange in their joint Rural Telecommunications program (Mgombelo and Braithwaite, 1992). A satellite station was already available at Southampton for the link, and VITA was contracted to create a groundstation in Tanzania. The main goals of the link were to:
The system become operational in July 1991. Future plans include a mobile packet radio station in Tanzania, and the addition of a server in Southampton to provide access to additional computing power for Tanzanian experiments in mapping, prospecting, weather prediction and other applications (Mgombelo and Braithwaite, 1992).
HealthNet utilizes a satellite called HealthSat-1 (UoSAT-3), a low-earth-orbit (LEO), sun-synchronous satellite that connects with a number of earth stations. Packet radio technology is used in the earth stations, which consist of a PC, radio transceiver, TNC, omni-directional antenna, and a variety of software to handle communication with the satellite. Because the satellite is in sun-synchronous orbit, uploading of email occurs during the same part of each day. HealthNet provides gateways to the Internet, BITNET, EARN, JANET, GREENET, and ADADEMNET and NGONET. Earth stations have been established in Zambia, Uganda, Tanzania, Kenya, Mozambique, the Congo, Malawi, Sudan, Zimbabwe, Cape Verde, Ghana, Mali, Cuba, and Brazil (SatelLife, 1992). HealthNet is used by health care-related organizations such as medical libraries, medical schools, health ministries, NGOs, and community groups in developing countries. Health care workers can use the network for a variety of purposes, including local and international email messaging, receiving health news, obtaining consultations, collecting and distributing statistics, and distance learning. HealthNet supports the "HealthNet Information Service" which provides a number of information-related programmes. These include (Shakakata, 1992):
Dialogue for Health. Health workers and professionals use HealthNet to communicate with their colleagues in their own region and in other parts of the world. They also have access for consultation to a number of medical institutions worldwide. Participating organizations include: Harvard School of Public Health (U.S.), the Liverpool School of Tropical Medicine (UK), the Oswaldo Cruz Institute (Brazil), the Universities of Zambia, Dar es Salaam, Mozambique, and Makerere (Africa), The Tropical Diseases Research Centre, and the World Health Organization. Interactive Publications for Health. Four publications are distributed on HealthNet: HealthNet News, African Medical Librarians Bulletin, WHO Library Digest, and AIDS Bulletin. Research Capabilities. CD-ROM drives attached to the earth stations provide access to MEDLINE for research purposes.
While packet radio is used in the satellite-ground station link, extensions beyond the ground station rely on telephone. Klein (1992) states that future plans for HealthNet call for the creation of telephone-based connections to the satellite ground station using FIDO technology. This configuration presently exists in Zambia, for example, where a FIDOnet-based network connects a satellite ground station to local organizations (Bennett, 1992). The ground station thus acts as a gateway between the ground-based FIDOnet network and the satellite.
With the assistance of VITA, the two banking cooperatives established a packet radio network, building upon a pre-existing voice radio network among the cooperatives. The purpose of the digital network was to "enhance the flow of commercial activities, create linkages and/or promote business consolidation among the cooperative rural banks and the allied cooperatives and organizations" (Guillermo, 1992:6). To create the network, packet radio equipment was integrated into some of the cooperative voice radio network, along with the addition of a centralized repeater. Specific applications of the network includes:
cooperative marketing information system. The network also supports the exchange of marketing information, such as trading commodity supply and demand, and pricing information. information exchange and communication applications. The network will support other general information applications such as technology transfer, problem solving, data transmission, oral and written communication, personnel supervision, program management, education and training, and emergency communications. 5.3.6 CEAMNET: Central AmericaThe Central American Network (CEAMNET) links nodes in five countries in Central America using packet radio. The network allows amateur and emergency communications throughout the Central American region (Hast, 1992). The network is based on ROSE software, which is based on X.121 addressing. It covers roughly 80% of Costa Rica, and has two links in Guatemala, one link in Honduras (with one other pending), one in El Salvador, and two in Panama. One link in Nicaragua awaits technical support for installation. The network connects a BBS to support the exchange of general interest information, electronic mail, with links to an international BBS network (Hast, 1992).5.3.7 ERNET: IndiaERNET is an academic and research network being developed by the Government of India to promote computer communications in India (Quarterman, 1990). Participants include the Indian Institutes of Technology (Delhi, Kanpur, Kharagpur, Madras, and Bombay), the Indian Institute of Science (Bangalore), the National Centre for Software Technology (Bombay), and the Department of Electronics, Government of India.The initial goal is to connect computing resources at eight academic and research institutions. Services supported are to be mail, file transfer, remote login, and database access.
Because a national public data network does not exist in India, and the telephone system is inadequate to support wide area networking, ERNET will use wireless technologies. These includes satellite network for its national backbone running X.25, and metropolitan area networks based on packet radio technology. Eventual plans call for the extension of the network beyond the initial sponsoring agencies to other cities and rural areas (Quarterman, 1990).
To create a WAN, a group of research institutions decided to use packet radio technology and avoid expensive dedicated leased lines. They used low-cost equipment from the amateur sphere, as well as readily available public domain software. A "grass-roots", bottom-up approach was used in which each institution set up and maintained its own packet radio station. The network is based on TCP/IP protocols, using the KA9Q software. VHF and UHF links are used, currently running at 1200 to 9600 bps. Work is underway to increase this speed to 56 Kbps. The institutions the packet radio WAN currently links include:
Several other institutions are in the process of joining the network. The packet radio WAN also has links to the Internet via the University of Aachen in Germany via the Indonesian packet switched network. Because this PSN "is known to be one of the most expensive PSNs in the world", alternative routes are being sought (Purbo, 1993:12). One alternative currently in operation is a link for electronic mail through VITA's LEO satellite. Two institutions linked by the packet radio WAN also have satellite ground stations. To expand the wireless WAN, the group has reverse engineered hardware and software components and are now mass producing the equipment (Purbo, 1993).
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