Divya Gopi Dack Net

Seminar 2004

DakNet

1. INTRODUCTION Now a day it is very easy to establish communication from one part of the world to other. Despite this even now in remote areas villagers travel to talk to family members or to get forms which citizens in-developed countries an call up on a computer in a matter of seconds. The government tries to give telephone connection in very village in the mistaken belief that ordinary telephone is the cheapest way to provide connectivity. But the recent advancements in wireless technology make running a copper wire to an analog telephone much more expensive than the broadband wireless Internet connectivity. Daknet, an ad hoc network uses wireless technology to provide digital connectivity. Daknet takes advantages of the existing transportation and communication infrastructure to provide digital connectivity. Daknet whose name derives from the Hindi word “Dak” for postal combines a physical means of transportation with wireless data transfer to extend the internet connectivity that a uplink, a cyber café or post office provides.

Dept of ECE

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GEC Thrissur

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DakNet

2. WHY DAKNET Real time communications need large capital investment and hence high level of user adoption to receiver costs. The average villager cannot even afford a personnel communications device such as a telephone or computer. To recover cost, users must share the communication infrastructure.

Real time

aspect of telephony can also be a disadvantage. Studies show that the current market for successful rural Information and Communication Technology (ICT) services does not appear to rely on real-time connectivity, but rather on affordability and basic interactivity. 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.

It is useful to consider non real-time infrastructures and applications such as voice mail, e-mail, and electronic bulletin boards. Technologies like storeand forward or asynchronous modes of communication can be significantly lower in cost and do not necessarily sacrifice the functionality required to deliver valuable user services. In addition to non real-time applications such as e-mail and voice messaging , providers can use asynchronous modes of communication to create local information repositories that community members can add to and query.

2.1 WIRELESS CATALYST Advances in the IEEE 802 standards have led to huge commercial success and low pricing for broadband networks. These techniques can provide broadband access to even the most remote areas at low price.

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DakNet

Important considerations in a WLAN are Security: In a WLAN, access is not limited to the wired PCs but it is also open to all the wireless network devices, making it for a hacker to easily breach the security of that network. Reach: WLAN should have optimum coverage and performance for mobile users to seamlessly roam in the wireless network Interference: Minimize the interference and obstruction by designing the wireless network with proper placement of wireless devices. Interoperability: Choose a wireless technology standard that would make the WLAN a truly interoperable network with devices from different vendors integrated into the same. Reliability: WLAN should provide reliable network connection in the enterprise network. Manageability: A manageable WLAN allows network administrators to manage, make changes and troubleshoot problems with fewer hassles. Wireless data networks based on the IEEE 802.11 or wifi standard are perhaps the most promising of the wireless technologies. Features of wifi include ease of setup, use and maintenance, relatively high bandwidth; and relatively low cost for both users and providers. Daknet combines physical means of transportation with wireless data transfer to extend the internet connectivity. In this innovative vehicle mounted access points using 802.11b based technology to provide broadband, asynchronous, store and forward connectivity in rural areas.

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GEC Thrissur

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DakNet

3. WIFI .

Wi-Fi refers to a set of high frequency wireless local area network

(WLAN) technologies more specifically referred to as 802.11a 802.11b and 802.11g. These standards are universally in use around the globe, and allow users that have a Wi-Fi capable device, like a laptop or PDA, to connect anywhere there is a Wi-Fi access point that is available. The three standards that are referred to signify the speed of the connection they are capable of producing. 802.11b ( which transmits at 11 Megabits per Second ) is the most common, although the faster Wi-Fi standards are quickly replacing it. Across the board, all of these Wi-Fi standards are fast enough to generally allow a broadband connection. Wi-Fi is an emerging technology that will likely be as common as electrical outlets and phone lines within a few years. Wi-Fi adds tremendous levels of convenience and increased productivity for workers whose offices are equipped with Wi-Fi, as well as travelers that can increasingly access Wi-Fi in airports, coffee shops, and hotels around world. A Wi-Fi network operates just like a wired network , without the restrictions imposed by wires. Not only does it enable users to move around and be mobile at home and at work, it also provides easy connections to the Internet and business networks while traveling. Wireless Fidelity, which is also known, as 802.11b is the corporate choice and has a suitably wide range for use in big office spaces. Wi-Fi is currently the most popular and least expensive wireless LAN specification. It operates in the 2.4GHz radio spectrum and can transmit data at speeds up to 11Mbps within 30m ranges. It can affect by interference from mobile phones and Bluetooth devices, which can reduce the transmission speeds. Wi-Fi is an emerging technology that will likely be as common as electrical outlets and phone lines within a few years.

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GEC Thrissur

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DakNet

Wi-Fi adds tremendous levels of convenience and increased productivity for workers whose offices are equipped with Wi-Fi, as well as travelers that can increasingly access Wi-Fi in airports, coffee shops, and hotels around. It is the standard fitment to many wireless laptops including the new Centrino based models.

Security Aspect In Wi-Fi technology, data is broadcast over the air using radio waves. This means that any WLAN – enabled computing device within reach of a wireless access point can reach of a wireless access point can receive data transmitted to or from the access point. Because radio waves travel through ceilings, floors and walls, the transmitted data can reach the wrong recipients on different floors or even outside the building. Intruders can use unsecured access points to get into corporate resources and launch denial-of-service attacks that can bog down servers with bogus requests and prevent user access to data and applications.

To ensure security, 802.11 wireless communications have a function called wired-equivalent privacy (WEP), a form of encryption, which provides privacy comparable to that of a traditional wired network. If the wireless network has some information that must be secured, WEP should be used to ensure data protection at traditional wired network levels. But as we know, there is never 100 percent security, and the WEP standard was itself breached. Of late, WPA (Wi-Fi protected Access) has over broken WEP as the de facto security standard for Wi_Fi alliance certification. WPA offers higher levels of wireless data security than WEP. It is a subset of the proposed 802.11i security standard from IEEE.

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DakNet

Specifications Max speed

- 11 MBPS

Max Encryption

- 128 bit WEP

Discrete channels

-3

Max range @full throughput - ~30 ft Natively compatible

- 802.11b, 802.11g

Potential user

- Entry level and home networks

3.1 ADVANTAGES OF WIFI ƒ

Uses an unlicensed part of the radio spectrum. This means less

regularly controls in many countries. ƒ

Frees network devices from cables, allows for a more dynamic network

to be grown. ƒ

Many reliable and bug-free Wi-Fi products on the market.

ƒ

Competition amongst vendors has lowered prices considerably since

their inception. ƒ

While connected on a Wi-Fi network, it is possible to move about

without breaking the network connection. ƒ

Moderns Access Points and Client Cards have excellent in-built security

and encryption. ƒ

Dept of ECE

Enterprise and Carrier Grade Access Points can

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3.2 DISADVANTAGES OF WIFI ƒ

The 802.11b and 802.11g flavors of Wi-Fi use the 2.4 GHz spectrum,

which is crowded with other devices such as Bluetooth, microwave ovens, cordless phones (900MHz or 5.8 GHz are therefore, alternative phone frequencies one can use if one has a Wi-Fi network), 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. ƒ

Power consumption is fairly high compared to other standards, making

battery life and heat a concern. ƒ

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. ƒ

Wi-Fi networks have limited range. A typical Wi-Fi home router using

802.11b might have a range of 150 ft (46 m) indoor and 300 ft (92 m) outdoors. But about 10 US$ and an hour of building will get you an antenna that can go much further.

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GEC Thrissur

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3.3

DakNet

AD-HOC NETWORK

An ad-hoc wireless network is a collection of wireless mobile hosts forming a temporary network without the aid of any established infrastructure or centralized control. Ad-hoc networks require a peer-to-peer architecture, and the topology of the network depends on the location of the different users, which changes over time. In addition, since the propagation range of a given mobile is limited, the mobile may need to enlist the aid of other mobiles in forwarding a packet to its final destination. Thus the end-to-end connection between any two mobile hosts may consist of multiple wireless hops. It is a significant technical challenge to provide reliable high speed end-to-end communications in ad-hoc wireless networks given their dynamic network topology, decentralized control and multihop connections.

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GEC Thrissur

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DakNet

In the ad-hoc network, computers are brought together to form a network "on the fly." As shown in Figure, there is no structure to the network; there are no fixed points; and usually every node is able to communicate with every other node. An algorithm in ad-hoc network architectures uses a broadcast and flooding method to all other nodes to establish who's who. Current research in ad-hoc wireless network design is focused on distributed routing. Every mobile host in a wireless ad-hoc network must operate as a router in order to maintain connectivity information and forward packets from other mobiles. Routing protocols designed for wired networks are not appropriate for this task, since they either lack the ability to quickly reflect the changing topology or may require excessive overhead. Proposed approaches to distribute routing that quickly adapt to changing topology without excessive overhead include dynamic source and associativity based routing. Other protocols that address some of the difficulties in supporting multimedia applications over ad-hoc wireless networks include rate-adaptive compression, power control, and resource allocation through radio clustering.

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DakNet

4. DAKNET NETWORK ARCHITECTURE The main parts of daknet architecture are ♦ Mobile access point ♦ Hub ♦ Kiosk

4.1 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 a 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.

Dept of ECE

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GEC Thrissur

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DakNet

Mobile Access Point is mounted on and powered by a bus or motorcycle, or even a bicycle with a small generator. MAPs are installed on vehicles that normally pass by each village to provide store-and-forward connectivity.

MAP equipment used on the bus includes, ¾

a custom embedded PC running Linux with 802.11b wireless card and

512 Mbytes of compact flash memory. ¾

a 100-mW amplifier, cabling, mounting equipment, and a 14-in omni

directional antenna. ¾

an uninterruptible power supply powered by the bus battery.

The total cost of the Daknet MAP equipment used on the bus is $580.A session occurs each time the bus comes within range of a kiosk and MAP transfers data. The speed of the connection between the access point and the kiosk or hub varies in each case. But on average, they can move about 21Mb or 42 Mb bidirectionally per session. The average good put or actual throughput for a session, during which the MAP and kiosk go in and out of connection because of mobility and obstructions, is 2.3Mbps. Omni directional antennas are uses on the bus and either directional or omni directional antennas are located at each of the kiosks or hubs. The actual throughput depends on gain of antenna and orientation of each kiosk with the road.

Dept of ECE

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GEC Thrissur

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DakNet

4.2 HUB It is a common connection point for devices in a network. It is used to connect segments of a LAN. It contains multiple ports. Packet at one port copied to all other ports-all segments see all packets. When the vehicle passes near an internet access point –the hub- it synchronizes all the data from different kiosks using the internet.

4.3 KIOSK It is a booth providing a computer related service such as ATM. In each village there is kiosk. It requires a user interface that can be used without training. It enable user to enter and display information on the same device. Either directional or omni directional antennas are located at each of the kiosks or hubs. Amplifiers are used to boost the signal and range for higher.

Dept of ECE

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GEC Thrissur

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DakNet

5. HOW DAKNET WORKS A simple store-and-forward WiFi system, using a government bus as a central linkage. The bus contains a simple WiFi installation and server, and when in range of one of the outlying information kiosks it synchronizes data for later processing. DakNet is a patented wireless package that does away with base stations. DakNet offers a cost-effective network for data connectivity in regions lacking communications infrastructure. Instead of trying to relay data over long distances, which can be expensive, Daknet transmits data over short point-topoint links between kiosks and portable storage devices called Mobile Access Points (MAP). Mounted and powered on a bus or motorcycle with a small generator MAP physically transports data between public kiosks and private communications devices and between kiosks and a hub (for non real time internet access). Low cost Wi-Fi radio transceivers transfer data stored in MAP at high bandwidth for each point-to-point connection. Daknet has thus two functions: ¾

As the MAP equipped vehicle comes within the range of a village Wi-Fi

enabled kiosk it automatically senses the wireless connection and uploads and downloads tens of mega bytes of data. ¾

As it comes in the range of Internet access points (the hub) it

automatically synchronizes the data from kiosks using the Internet.

These steps repeat or all the vehicles carrying MAP, thus providing a low cost wireless network and seamless communication infrastructure. Even a single vehicle passing by a village is sufficient to carry the entire daily information. 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 20MB in one direction.

Dept of ECE

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GEC Thrissur

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DakNet

Thus asynchronous broadband connectivity offers a stepping-stone to always on broadband infrastructure and end user applications. Daknet makes it possible for individual households and private users to get connected. Daknet network architecture

The average cost to make a village kiosk ready is $185. Assuming each bus serves 10 villages the average cost for enabling each village is $243.

DakNet offers an affordable and complete connectivity package, including: ƒ

Wireless hardware (wireless transceiver and antennas)

ƒ

Networking software

ƒ

Server and cache software

ƒ

Custom applications, including email, audio/video messaging, and

asynchronous Internet searching and browsing ƒ

API enabling organizations to easily integrate DakNet with their existing

applications.

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GEC Thrissur

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DakNet

6. DAKNET IN ACTION Villagers in India and Cambodia are 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 the Daknet’s early deployments was as an affordable rural connectivity solution for the Bhoomi e-governance project. DakNet is also implemented in a remote province of Cambodia for 15 solar-powered village schools, telemedicine clinics, and a governor’s office. Daknet is currently in action in many places. They are, ¾

Bhoomi initiative in Karnataka

¾

SARI (Sustainable Access for Rural India) project of Tamilnadu

¾

Ratnakiri project in Cambodia

6.1

BHOOMI INITIATIVE IN INDIA Bhoomi, an initiative to computerize the land records of villagers is the

first e-governance project in India. Bhoomi has been successfully implemented at district headquarters across the state to completely replace the physical land records system. Daknet makes Bhoomi’s land records database available to villagers’ 40km away from the district headquarters. In this deployment a public bus is outfitted with a Daknet MAP, which carries the land record requests from each village kiosk to the taluka server. The server then processes the requests and outputs land records. The bus then delivers the records to each village kiosk and the kiosk manager prints the records and collects Rs 15 per record.

Dept of ECE

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GEC Thrissur

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DakNet

Villagers along the bus route have enthusiastically welcomed the system. They are grateful in avoiding the long trip to the main city to collect the records. The average total cost of the equipment used to make a village kiosk or hub DakNetready 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). It has also been successfully employed in the villages of Cambodia. Next steps involve combining DakNet and Bhoomi with a package of applications to provide a sustainable model for rural entrepreneurship.

The Government of Karnataka plans to use Bhoomi as the backbone for providing other kinds of information of relevance to rural areas. This includes commodity prices, information on agricultural inputs, social assistance like old age, widow and physically handicapped pensions etc. There are also plans to extend these kiosks to the village level by involving private sector entrepreneurs and gram panchayats (local governance units) on a revenue-sharing basis.

Dept of ECE

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GEC Thrissur

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DakNet

7. FEATURES OF DAKNET Since it avoids using phone lines or expensive equipment, Daknet provides one of the lowest-cost accessibility solutions in the world. In addition to low cost the other feature of Daknet is its ability for upgrading the always-on broadband connectivity. As the village increases its economic means the villagers can use the same hardware, software and user interface to enjoy real-time information access. The only change is the addition of fixed location wireless antennas and towers, a change that is entirely transparent to end users, because they need not learn new skills or buy new hardware and software. With multiple MAP buses, a low cost wireless network and seamless communication infrastructure gets created.

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GEC Thrissur

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DakNet

8. FUTURE DEVELOPMENTS Daknet provide 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 real time information access. The only change is the addition of fixes location wireless antennas and towers. If the mobile access points are replaced with fixed transceivers real-time connectivity is possible. Thus more sophisticated services, such as voice over internet protocol (VoIP) is enabled which allows normal real time telephony. Instead of using wifi, wi-max or e-video can be used. Wifi can affected by interference from mobile phones and Bluetooth devices which will reduce the transmission speeds.

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DakNet

9. CONCLUSION Daknet’s low deployment cost and enthusiastic reception by rural users has motivated dozens of inquiries for further deployments. This provides millions of people their first possibility for digital connectivity. Increasing connectivity is the most reliable way to encourage economic growth. The larger goal is to shift the policy focus of the Government’s universal service obligation funds from wireless village telephones to wireless ad-hoc networking. The shift will probable require formal assessment for user satisfaction, resulting economic growth and system reliability.

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10. REFERENCES IEEE Computer, January 2004 Electronics For You, April 2004 www.daknet.net www.medialabasia.org www.firstmilesolutions.com

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