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DAKNET:
Rethinking Connectivity in Developing Nations
ABSTRACT
This paper outlines a migration path towards universal broadband connectivity, motivated by the design of a wireless store-and-forward communications network.
We argue that the cost of real-time, circuit-switched communications is sufficiently high that it may not be the appropriate starting point for rural connectivity. Based on market data for information and communication technology (ICT) services in rural India, we propose a combination of wireless technology with an asynchronous mode of communications to offer a means of introducing ICTs with:
¢ affordability and practicality for end users;
¢ a sustainable cost structure for operators and investors;
¢ a smooth migration path to universal broadband
connectivity.
A summary of results and data are given for an operational pilot test of this wireless network in Karnataka, India, beginning in March 2003.
We also briefly discuss the economics and policy considerations for deploying this type of network in the context of rural connectivity.
CONTENTS
1 Introduction
2 Wireless Catalyst
3 Mobile Ad Hoc Connectivity
* Seamless Scalability
* Economics
4 Daknet
5 Wifi
* Advantages
* Disadvantages
6 Daknet Network Architecture
7 Conclusion
8 Reference
INTRODUCTION
As a government representative enthusiastically talks about the new telephone for a village in remote rural India, a villager asks, Who am I going to call I donâ„¢t know anybody who owns a telephone. Yet, despite this sensible observation, a phone is dutifully installed as part of the current government mandate to connect villages to neighbouring towns. Although some villagers do use the phone occasionally, most still travel sometimes days to talk to family or to obtain the forms and other data that citizens in developed nations can call up on a computer in a matter of seconds.
In short, the goal of broadband connectivity for everyone has been shelved in favor of cutting back to the minimum possible standard telephone service in the mistaken belief that this is the cheapest way to provide connectivity. This compromise is particularly tragic given recent advances in wireless technology, which make running a copper line to an analog telephone far more expensive than broadband wireless Internet connectivity. Rather than backpedal on the goal of connecting everyone, society should be thinking, How can we establish the kernel of a user network that will grow seamlessly as the villageâ„¢s economics develop In other words,what is the basis for a progressive, market-driven migration from government seed services- e-governance -to universal broadband connectivity that local users will pay for
DakNet, an ad hoc network that uses wireless technology to provide asynchronous digital connectivity, is evidence that the marriage of wireless and asynchronous service may indeed be that kernel -the beginning of a road to universal broadband connectivity. Developed by MIT Media Lab researchers, DakNet has been successfully deployed in remote parts of both India and Cambodia at a cost two orders of magnitude less than that of traditional landline solutions. Villagers now get affordable Internet services-and theyâ„¢re using them. As one man in a small village outside of New Delhi remarked, This is better than a telephone!
THE WIRELESS CATALYST
Recent advances in wireless computer networking-particularly the IEEE 802 standardsâ€have led to huge commercial success and low pricing for broadband networks. While these networks are viewed as mainly for offices or for hotspots in urban areas, they can provide broadband access to even the most remote areas at a low price. Today, wireless cell phone and wireless local loop (WLL) service costs roughly a third of copper or fiber landline service, while packet-based broadband computer networks cost roughly a ninth of the landline serviceâ€and they are far friendlier to data services and to lower-grade voice service such as voice messaging. These new technologies thus offer developing countries an opportunity to leapfrog over wireline and WLL telephony infrastructure to the forefront of broadband communications technology.
Wireless data networks based on the IEEE 802.11, or WiFi, standard are perhaps the most promising of the wireless technologies. The forces driving the standardization and proliferation of WiFi in the developed world have resulted in features that can stimulate the communications market in the developing world. These features include ease of setup, use, and maintenance; relatively high bandwidth; and, most important, relatively low cost for both users and providers.
As one demonstration of the practicality of this new technology for rural connectivity, researchers from the Indian Institute of Technology at Kanpur, working with Media Lab Asia , have unwired a 100-sq km area of the Gangetic Plain in central India. Figure 1 shows the corridor. This project provides broadband connectivity along a corridor with almost one million residents, at a projected one-time cost of under $40 per subscriber. Other experiments have shown the practicality of the technology in mountainous terrain and in city centers. Indeed, several cities in the US have begun to deploy free Internet connectivity using IEEE 802.11b. Even with advances such as those demonstrated in the Digital Gangetic Plain project, the cost of realtime,circuit-switched communications is sufficiently high that it may not be the appropriate starting point for rural connectivity in developing nations.Market data for information and communication technology (ICT) services in rural India strongly implies that asynchronous service-voice messaging, e-mail, and so on-may be a more cost-effective starting point for rural connectivity projects.
MOBILE AD HOC CONNECTIVITY
The DakNet wireless network takes advantage of the existing communications and transportation infrastructure to distribute digital connectivity to outlying villages lacking a digital communications infrastructure. DakNet, whose name derives from the Hindi word for post or postal, combines a physical means of transportation with wireless
data transfer to extend the Internet connectivity that a central uplink or hub, such as a cybercafé , VSAT system, or post office provides. As Figure 2 shows, instead of trying to relay data over a long distance, which can be expensive and power-hungry, DakNet transmits data over short point-to-point links between kiosks and portable storage devices, called mobile access points (MAPs). Mounted on and powered by a bus, a motorcycle, or even a bicycle with a small generator, a MAP physically transports data among public kiosks and private communications devices (as an intranet) and between kiosks and a hub (for nonreal-time Internet access). Low-cost WiFi radio transceivers automatically transfer the data stored in the MAP at high bandwidth for each point-to-point connection.
DakNet operation thus has two steps:
¢ As the MAP-equipped vehicle comes within range of a village WiFi-
enabled kiosk, it automatically senses the wireless connection and
then uploads and downloads tens of megabytes of data.
¢ When a MAP-equipped vehicle comes within range of an Internet
access point (the hub), it automatically synchronizes the data from all
the rural kiosks, using the Internet. The steps repeat for every vehicle
carrying a MAP unit, thereby creating a low-cost wireless network
and seamless communications infrastructure.
An ad hoc network is a collection of autonomous nodes or terminals that communicate with each other by forming a multihop radio network and maintaining connectivity in a decentralized manner. Since the nodes communicate over wireless links, they have to contend with the effects of radio communication such as noise, fading and interference. In addition, the links typically have less bandwidth than in a wired network. Each node in a wireless ad hoc network functions as both a host and a router and the control of the network is distributed among the nodes. The network topology is in general dynamic, because the connectivity among the nodes may vary with time due to nodes departure, new node arrivals, and the possibility of having mobile nodes.
Giving everyone access to digital messaging-voice mail, digital documents, e-mail, and so on-is better than installing a community telephone. Rural information and communication technology (ICT) is typically introduced as a communications channel that the community shares. Whether through a public call office (PCO) or a public computer kiosk, users are introduced to ICT as shared utilities with a technically literate operator acting as an intermediary.
In this shared-use model, much ICT has relied on real-time
communications , such as landline telephone, cellular phone, or satellite radio links. These real-time technologies can be useful for immediate interactivity and accessing highly time-sensitive information.
Successful examples include Indiaâ„¢s PCOs and the Grameen Phone initiative .While successful at providing basic services, the strategy of deploying shared, real-time communications also has serious drawbacks. One is the large capital investment in a real-time infrastructure, which requires a high level of user adoption to recover costs. The average villager cannot even afford a personal communications device such as a telephone or computer, let alone a subscription fee for access to the communications infrastructure.Hence, to recover cost, users must share the communications infrastructure. This limits the all-important value added from network effects. A villager who finds no use for a phone is typical, and this is perhaps why so few of the worldâ„¢s poor have used a telephone.
The real-time aspect of telephony can also be a disadvantage:
Both intended parties must be present at each terminal to capture the infrastructureâ„¢s full value. If a caller wishes to contact someone who does not own (or is not present at) a telephone, the communication is asynchronous despite the real-time infrastructure.Some kind of additional messaging mechanism (be it a messenger or an answering machine) is required to deliver the callerâ„¢s message to its destination.
As a consequence, real-time telephony can reinforce gaps among rural populations since it encourages users to communicate mainly with people who have private phone lines, typically those of higher economic status located in more urban areas. In the Grameen-Phone initiative, women were chosen as the community operators to help reduce this effect, since it was socially acceptable for women to deliver messages to everyone in the village.
Until widespread private ownership of ICT devices becomes economically feasible for end users, it may be useful to consider non-real-time infrastructures and applications such as voice mail, e-mail, and electronic bulletin boards. Also known as store-and-forward or asynchronous modes of communication, these technologies can be significantly lower in cost and do not necessarily sacrifice the functionality required to deliver valuable user services. They might also be more practical and socially appropriate for users than a shared real-time communications infrastructure.
The poor not only need digital services, but they are willing and able to pay for them to offset the much higher costs of poor transportation, unfair pricing, and corruption. Some rural service providers (RSPs) have achieved profitability by offering lower-cost substitutes for a villagerâ„¢s existing information, communication, and transportation expenses. For instance, Drishtee provides an e-government platform that lets villagers interact with local government offices remotely from a kiosk in their village that is managed by a trained operator. A variety of services such as filing a complaint, applying for a loan, and requesting a driverâ„¢s license are generating up to $2,000 per year per kiosk for Drishtee. The significant demand for these services results from a sound value proposition: Save villagers time and money. Drishteeâ„¢s success suggests that the introduction of ICT in rural areas might not have anything to do with technology. Much rural ICT starts with a specific technology and then tests out a variety of information and communication services to see which get accepted (a push approach). A better strategy might be to start with a basic serviceâ€in Drishteeâ„¢s case, aggregating demand and brokering information exchange between the villager and the governmentâ€and then see how technology
can support and streamline that service. Drishtee determined that computers and available connectivity were enough to capture, send, and receive information electronically.Like other RSPs, however, Drishtee is constrained by Indiaâ„¢s lack of a viable communications infrastructure. Many of the villages that Drishtee operates in lack working phone lines because of poor line maintenance and delayed installations. As a result, Drishtee has resorted to sneaker net, an asynchronous approach to connectivity that involves transporting and swapping floppy disks from the village to the government center and back again. Despite this labor-intensive approach, sneaker net is successful because Drishteeâ„¢s applications that generate the most revenue require only intermittent connectivity.
Asynchronous ICT services are sufficient to meet most rural community needs. The Sustainable Access for Rural India (SARI) project in Tamil Nadu, Indiaâ€a joint endeavor by the MIT Media Lab, the Harvard Center for International Development, and the Indian Institute of Technology, Madrasâ€recently collected data about the communications needs, habits, and costs in hundreds of rural Indian households to gauge the desire for and perceived affordability of household communications. The study found that the current market for successful rural ICT services does not appear to rely on real-time connectivity, but rather on affordability and basic interactivity: Rural ICT companies should start their operations by first focusing on providing basic communication and information services rather than more sophisticated applications. Another SARI analysis done by McKinsey Consulting indicates that although the universe of potential applications is large, in the short-term only e-mail, scan-mail, voice-over-e-mail and chat are likely to be revenue-generating applications. The McKinsey report also found that most of SARIâ„¢s applications do not require real-time connectivity. It estimates that 50 percent of all existing rural mail will convert to e-mail, and people often preferred voice messaging to a real-time voice channel. Both e-mail and voice messaging are non-real-time applications. In addition to these non-real-time applications, providers can use asynchronous modes of communication to create local information repositories that community members can add to and query. For example, a villager can access information from a computer somewhere outside the community and store that information in a village repository so that others can use it. This approach is particularly viable because the cost of digital storage is decreasing faster than the cost of most communication technologies. Moreover, users are apt to find the information in a local repository highly relevant, which further decreases their reliance on a real-time infrastructure and international bandwidth. Users could search and browse the Web in non-real time through applications developed for low-connectivity environments such as TEK.
Even a single vehicle passing by a village once per day is sufficient to provide daily information services.The connection quality is also high. Although DakNet does not provide real-time data transport, a significant amount of data can move at once-typically 20 Mbytes in each direction.
Indeed, physically transporting data from village to village by this means generally provides a higher data throughput than is typical with other low-bandwidth technologies such as a telephone modem.
Seamless scalability
In addition to its tremendous cost reduction, a critical feature of DakNet is its ability to provide a seamless method of upgrading to always-on broadband connectivity. As a village increases its economic means, its inhabitants can use the same hardware, software , and user interface to enjoy realtime
information access. The only change is the addition of fixed-location wireless antennas and towersâ€a change that is entirely transparent to end users because they need not learn any new skills or buy any new hardware or software. The addition of fixed transceivers would provide real-time connectivity, thus enabling new, more sophisticated services, such as voice over IP, which allows normal real-time telephony. Thus, as the Some Common Myths about Rural Information and Communication Technology sidebar describes, asynchronous broadband wireless connectivity offers a practical stepping-stone and migration path to always-on, broadband infrastructure and end-user applications. Together with the development of two other key rural communication componentsâ€robust, low-cost terminals and local user-interface design and applications - DakNet makes it practical for individual households and private users to get connected.
Economics
A back-of-the-envelope calculation for DakNet suggests that a capital investment of $15 million could equip each of Indiaâ„¢s 50,000 rural buses with a $300 MAP and thereby provide mobile ad hoc connectivity to most of the 750 million people in rural India. This figure represents a cost that is orders of magnitude lower than other rural communication alternatives. Costs for the interactive user devices that DakNet supportsâ€including thin-client terminals, PDAs, and VoIP telephonesâ€may also soon become far more affordable than traditional PCs or WLL equipment.PDA-like devices using an IEEE 802-like wireless protocol retail for $100, with a manufacturing cost of approximately $50.System-on-a-chip technology is lowering these costs even more, potentially enabling wireless PDAs at prices as low as $25 .
DAKNET IN ACTION
Villages in India and northern Cambodia are actively using DakNet with good results. Local entrepreneurs currently are using DakNet connections to make e-services like e-mail and voice mail available to residents in rural villages.
One of DakNetâ„¢s earliest deployments was as an affordable rural connectivity solution for the Bhoomi e-governance project. In September 2003,we also implemented DakNet in a remote province of Cambodia for 15 solar-powered village schools, telemedicine clinics, and a governorâ„¢s office.
Bhoomi initiative in India
Bhoomi, an initiative to computerize land records, is recognized as the first national e-governance initiative in India. Pioneered by the State Government of Karnataka, Bhoomi has been successfully implemented at district headquarters across the state to completely replace the physical land records system.DakNet makes Bhoomiâ„¢s land records database available to villages up to 40 km away from Bhoomiâ„¢s district headquarters,or taluka, in Doddaballapur. In this deployment,we outfitted a public government bus with a DakNet MAP to transport land record requests from each village kiosk to the taluka server. The server processes requests and outputs land records. The bus then delivers the records to each village kiosk, where the kiosk manager prints them out and collects a payment of 15 rupees (US$0.32) per land record. The bus passes by the hub and stops at each village six times per day(three round-trips).A session occurs each time the bus comes within range of a kiosk and the MAP transfers data.The average length of a session is 2 minutes and 34 seconds, during which the MAP transfers an average of 20.9 Mbytes unidirectionally (kiosk to MAP or MAP to kiosk) and up to twice that amount bidirectionally (from kiosk to MAP and MAP to kiosk).
The average goodput (actual data throughput)for a session, during which the MAP and kiosk go in and out of connection because of mobility and obstructions, is 2.47 Mbps. These averages are based on repetitive testing in a sample group of villages that reflect the range of different antenna configurations. The team used both omnidirectional and directional antennas with differing gains according to the orientation of each kiosk with the road and the bus stop.
The total cost of the DakNet MAP equipment used on the bus is $580, which includes
¢ a custom embedded PC running Linux with 802.11b wireless card
and 512 Mbytes of compact flash memory;
¢ a 100-mW amplifier, cabling, mounting equipment, and a 14-in
omnidirectional antenna; and
¢ an uninterruptible power supply powered by the bus battery.
The average total cost of the equipment used to make a village kiosk or hub DakNet-ready was $185. Assuming that each bus can provide connectivity to approximately 10 villages, the average cost of enabling each village was $243 ($185 at each village plus $580 MAP cost for 10 villages).Villagers along the bus route have enthusiastically received the DakNet-Bhoomi system. They are grateful to avoid making the long, expensive trip into the main city to obtain land records.
DakNet: A Last Mile Solution
The Internet is the nervous system of our planet and the billions of people who lack the proper telecommunications infrastructure are seen as the "last mile problem". “First Mile Solutions
Many technologies have been introduced to the world with in the last 30 years. Through them we have sent men to the moon and are able to communicate with individuals face to face from half way around the world. These advances have brought progress to the USA and other first world countries and have become the standard. It has become a vital engine of growth for the world economy. Despite these advances the entire world has not been able to take advantage of those advancements for several reasons.
Poor telecommunication lines
Lack of local economy for development of infrastructure
Awareness about the technological advantages
The firm First Mile Solutions has taken it upon themselves to start introducing the information technologies to rural areas in the developing world. Their projects use existing infrastructures to introduce technologies to villages through unique solutions, such as Daknet. Dak means, post in Hindi. Creating an electronic postal network, complete with electronic Postmen (Boyd, Clark).
DakNet Mobile Access Point (MAP) Networks require:
¢ Appropriate Environment: computers in remote villages that can be accessed by road transport.
¢ Approach: MAPs are installed on vehicles that normally pass by each village to provide store-and-forward connectivity
Daknet allows rural villages to exchange messages and video through a mobile ISP. By mounting a wireless card on a vehicle that travels around to remote villages and exchanges updated information with each kiosk it encounters through WiFi.
Villagers are able to send message and record videos through these kiosks. That data is stored in the outbox of the kiosk. When the mobile vehicle comes around it exchanges the data in the outbox and the inbox. Those awaiting messages are able to check the inbox for any messages or videos. All information is downloaded to the central system at the office station.
Using WiFi allows for cheap reliable Internet service to those rural communication Infrastructures. The telephone lines in the remote and rural areas are frequently dysfunctional and unreliable for Internet connectivity. (Baatchit) Thus WiFi creates better access to bandwidth from the large data lines that run throughout the world (BELOW: Titanic backbone through Asia. (Titanic))
The latest installation to DakNet has been adding the remote region of Ratanakiri, Cambodia. A collection of 13 villages that are only accessible by motorcycle and oxcart. The per capita income is roughly under $40 US dollars. The area school is equipped with solar panels that run the computer for six hours a day. Providing them now with email and video messaging.
Early every morning, five Honda motorcycles leave the hub in the provincial capitol of Banlung where a satellite dish, donated by Shin Satellite, links the provincial hospital and a special skills school to the Internet for telemedicine and computer training. The moto drivers equipped with a small box and antenna at the rear of their vehicle, that downloads and delivers e-mail through a wi-fi (wireless) card, begin the day by collecting the e-mail from the hub's dish, which takes just a few seconds.
Through the donations from various organizations the developing world is given an opportunity to participate in the technological revolution. After many pilot projects there are still investigations to understanding how to increase the projects through various solutions such as DakNet. Daknetâ„¢s next installation is projected for another group of villages in Cambodia in November.
First Mile Solutions: DakNet Takes Rural Communities Online
Many developing countries continue to face the challenge of how to increase access to information communication technologies (ICTs) in rural and remote areas. Telecommunication companies are usually reluctant to extend their network due to high infrastructure costs, low population density, and limited ability to pay for the services. First Mile Solutions [1] (FMS) counters this problem by providing telecommunications equipment that can cheaply connect rural and remote populations to the Internet through an innovative technology: DakNet. DakNet leverages short- range wireless technology in tandem with traditional telecommunication and physical transportation infrastructures. Local transportation†e.g., public buses, motorcycles, and supply trucks†facilitates data exchanges between rural villages and Internet hubs. This unconventional communication network provides end users with asynchronous access to e- mail, voice messages, and Internet browsing.
Activity Description: Villagers in Cambodia, Costa Rica, Rwanda, Paraguay and India are getting connected to the global network, using technology from Massachusetts-based First Mile Solutions. FMS' DakNet technology provides connectivity to villages through a unique drive-by WiFi technique. The project provides e-mail addresses, phone services and web capability to individual villagers. While they are not always connected to the network, villagers can access them any time to write e-mail, record messages or conduct web searches. Every day, a vehicle drives slowly into the village, uploading stored data and downloading them to the central machines. When the vehicle returns to the base station, data are uploaded to a satellite and can be sent anywhere in the world.
Activity Update: FMS now reaches 40,000 villagers through its various projects and is unrolling its first local branch in India. The company plans to spend $30 million over the next six years to reach India's market capacity of 220,000 villages. After the start-up phase is complete, this system will be entirely financed by private investment and profits from low service fees. For the purpose of spreading United Villages services to other countries where operations are not currently active, the company has begun offering a franchise service open to qualified entrepreneurs.
FMS has three major future projects in the pipeline. They plan to utilize cellular networks to transfer data to their customers, eliminating the need for most Fixed Access Points. The company also plans to begin offering a private internet currency service whereby users may purchase goods using credit from their prepaid United Villages accounts. Finally, FMS is in preliminary talks with major search engine providers to create innovative new caching technology that would essentially offer many internet services in an offline format.
It is an initiative led by First Mile Solutions (FMS), a venture
managed by a team of MIT graduates, developing and testing innovative
connectivity approaches aiming at rural needs in developing
countries. A pilot demonstration took place in Tikawali, a village
near Faridabad (State of Haryana, India) in March 2002. The pilot
solution enabled villagers to file complaints via email and send
video messages from one village to another. The solution combines
WiFi (IEEE 802.11b) equipment at 2.4Ghz with Mobile Access Points
(MAPs) mounted on and powered by a public bus. The pilot proved able
to wirelessly and automatically collect, transport and deliver data
at high speeds to and from kiosk-based computers enabled with WiFi
cards.
Testing Wi-Fi with data store-and-forward solutions in rural India will not be confined to pilot projects anymore. The government has proposed to roll out the DakNet Wi-Fi project - involving the linking up of computers to networks without using wires - as a connectivity medium aimed at the rural masses, according to the department of industrial policy and promotion secretary Rajeeva Ratna Shah.
The pilot projects have proved their ability to wirelessly and automatically collect, transport and deliver data at high speeds to and from kiosk-based computers with Wi-Fi cards, he told EFE on the sidelines of the fourth India-EU business summit here. He, however, refused to reveal the project details as well as the time frame as to when the project will be rolled out. Pilot projects such as the one currently on in Karnataka, are fast proving that Wi-Fi technologies can actually bring connectivity to underserved populations at a fraction of the cost of alternative wired or wireless technologies, Mr Shah said.
According to First Mile Solutions founder Amir Alexander Hasson, who helped initiate the two DakNet Wi-Fi pilot projects in Tikawali, a village near Faridabad, Haryana, and Dodabalapur district in Karnataka, We are using IEEE 802.11b equipment at 2.4 GHz. We donâ„¢t use base stations, but rather our custom DakNet Mobile Access Point (MAP) that is mounted on and powered by a vehicle.
Giving the project details, Mr Hasson said, Essentially, a van roam roams around the Dodabalapur district in Karnataka, stopping at different villages long enough for the local computer to connect to it wirelessly and transfer the data stored in it. From the van to the central database is also a Wi-Fi hop, thus resulting in a wireless end-to-end transfer of information - which is what Wi-Fi is all about. The project involves creating an online database of land records.
Essentially, the DakNet-enabled vehicle drives past a kiosk where it picks up and drops off land record queries and responses. Each day, this is synchronised with a central database. Data is transported through the access point, which automatically and wirelessly collects and delivers data from each kiosk on the network. The transfer of data can take place up to a radius of 1.25 km around the kiosk.
Mr Hasson said, The benefits of using this low-cost wireless network which is easy to set up and maintain are already emerging.
DakNet offers a cost-effective network for data connectivity in regions lacking communications infrastructure. The patent-pending hybrid network architecture combines physical and wireless data transport to enable high-bandwidth intranet and Internet connectivity among kiosks (public computers) and between kiosks and hubs (places with a reliable Internet connection).
Data is transported by means of a mobile access point, which automatically and wirelessly collects and delivers data from/to each kiosk on the network. Daknet focuses on bridging the digital divide by extending the advantages of 802.11x technologies and solutions to the remote areas.
WIFI
Short for wireless fidelity and is meant to be used generically when referring of any type of 802.11 network, whether 802.11b, 802.11a, dual-band, etc. The term is promulgated by the Wi-Fi Alliance. Formerly, the term "Wi-Fi" was used only in place of the 2.4GHz 802.11b standard, in the same way that "Ethernet" is used in place of IEEE 802.3. The Alliance expanded the generic use of the term in an attempt to stop confusion about wireless LAN interoperability.
Wireless data networks (Wide Area Networks and Local Area Networks) based on the IEEE 802.11 or WiFi standard are perhaps the most promising wireless technology. Given its popularity in developed nations, it is reasonable to consider the use of WiFi in developing countries as well. The forces driving the standardization and proliferation of WiFi in the developed world could also stimulate the communications market dynamic in the developing world. These features include: its ease of set-up, use, and maintenance; its relatively high bandwidth; and, most importantly, its relatively low cost for both users and providers.
Standard WiFi connectivity (IEEE 802.11b) provides up to 11Mb/sec data rates, and operates in a band near 2.4Ghz that is generally unlicensed in Europe and the Americas. Newer versions of WiFi provide 22Mb/sec in this band, and versions that operate at higher frequencies provide up to 54Mb/sec. Tests in rural settings show that a standard WiFi card (such as commonly used with laptop PCs) can provide good connectivity up to a ½ kilometer radius given line-of-sight. With the addition of antennas and repeaters, it is possible to achieve point-to-point connectivity at distances of up to 20 kilometers. WiFi access points (devices commonly used to provide a WiFi network) currently retail for $120, and WiFi cards retail for under $60. WiFi technology opens up new possibilities for rural connectivity in developing countries. However, the successful implementation of this technology and the choice of usage model should be guided by an intimate knowledge of rural communities and their information- and communication-related needs. Our vision is that, provided a conducive regulatory environment, local entrepreneurs within developing countries will leverage WiFi-based technology to: (a) solve the chicken-and-the-egg problem of the simultaneous need for both a market and an infrastructure; and (b) create a widespread wireless infrastructure that grows seamlessly with the rural communications market, ultimately scaling up to universal broadband connectivity.
Specifications
Max speed - 11 MBPS
Max encryption - 128 bit WEP
Discrete channels - 3
Max range @ full throughput - 30ft
Natively compatible - 802.11b,802.11g
Potential user - Entry level and home networks
ADVANTAGES OF WIFI
¢ Uses an unlicensed part of the radio spectrum.This means less regularly controls in many countries.
¢ Frees network devices from cables,allows for a more dynamic network to be grown
¢ Many reliable and bug-free Wi-Fi products on the market.
¢ Competition amongst vendors has lowered prices considerably since their inception.
¢ While connected on a Wi-Fi network,it is possible to move about without breaking the internet connection.
¢ Modern Access points and Client Cards have excellent in-built security and encryption.
DISADVANTAGES OF WIFI
¢ The 802.11b and 802.11g flavours of Wi-Fi use the 2.4GHz spectrum which is crowded with other devices such as Bluetooth, microwave ovens, cordless phones(900MHz or 5.8GHz ), video sender devices among many others. This may cause degradation in performance. Other devices which use microwave frequencies such as certain types of cell phones , can also cause degradation in performance.
¢ Power consumption is fairly high compared to other standards, making battery life and heat a concern.
¢ Users do not always configure it properly. In addition, Wi-Fi commonly uses Wired Equivalent Privacy (WEP) protocol for protection, which has been shown to be easily breakable even when properly configured. Newer wireless solutions are slowly providing support for the superior Wi-Fi Protected Access (WPA) protocol, though many systems still employ WEP.
¢ Wi-Fi networks have limited range. A typical Wi-Fi home router using 802.11b might have a range of 150 ft(46 m) indoors and 300 ft (92 m) outdoors. But about 10 US$ and an hour of building will give you an antenna that can go much further.
DAKNET NETWORK ARCHITECTURE
The main parts of daknet architecture are:
¢ Mobile access point
¢ Hub
¢ Kiosk
MOBILE ACCESS POINT
Daknet offers data to be transmitted over short point-to-point links.It combines physical and wireless data transport to enable high bandwidth intranet and internet connectivity among kiosks (public computers) and between kiosks and hubs(places with reliable Internet connection) .Data is transported by means of mobile access point, which automatically and wirelessly collects and delivers data from/to each kiosk on the network. Low cost WIFI radio transceivers automatically transfer the data stored in the MAP at high bandwidth for each point-to-point connection.
CONCLUSION
DakNet will enlighten rural India to the Internet
The government has proposed to roll out the DakNet Wi-Fi project - involving the linking up of computers to networks without using wires - as a connectivity medium aimed at the rural masses.
According to First Mile Solutions founder Amir Alexander Hasson, who helped initiate the two DakNet Wi-Fi pilot projects in Tikawali, a village near Faridabad, Haryana, and Dodabalapur district in Karnataka, "We are using IEEE 802.11b equipment at 2.4 GHz. We don't use base stations, but rather our custom DakNet Mobile Access Point (MAP) that is mounted on and powered by a vehicle."
Giving the project details, Mr Hasson said, "Essentially, a van roam roams around the Dodabalapur district in Karnataka, stopping at different villages long enough for the local computer to connect to it wirelessly and transfer the data stored in it. From the van to the central database is also a Wi-Fi hop, thus resulting in a wireless end-to-end transfer of information - which is what Wi-Fi is all about. The project involves creating an online database of land records."
Essentially, the DakNet-enabled vehicle drives past a kiosk where it picks up and drops off land record queries and responses. Each day, this is synchronized with a central database. Data is transported through the access point, which automatically and wirelessly collects and delivers data from each kiosk on the network. The transfer of data can take place up to a radius of 1.25 km around the kiosk.
REFERENCE
¢ cs.cmu.edu
¢ thinkcycletc-filesystem
¢ thinkcycle2.media.mit.edu
¢ firstmilesolutions.com
¢ daknet.net
¢ digitalpartnersdrishtee.html
