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DacknetTRANSCRIPT
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.
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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 store- and 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
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messaging , providers can use asynchronous modes of
communication to create local information
repositories that community members can add to and
query.
2.1WIRELESS 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.
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.
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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.
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
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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
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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.
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
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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.
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
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Potential user - Entry level and home
networks
3.1 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
network connection.
Moderns Access Points and Client Cards have
excellent in-built security and encryption.
Enterprise and Carrier Grade Access Points can
3.2 DISADVANTAGES OF WIFI
The 802.11b and 802.11g flavors of Wi-Fi use the
2.4 GHz spectrum, which is crowded with other
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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.
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) 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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3.3 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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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
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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.
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
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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.
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,
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 omni directional
antenna.
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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 bi-
directionally 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.
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-
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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.
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.
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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-to-
point 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:
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.
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
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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.
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
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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:
Wireless hardware (wireless transceiver and
antennas)
Networking software
Server and cache software
Custom applications, including email, audio/video
messaging, and asynchronous Internet
searching and browsing
API enabling organizations to easily integrate
DakNet with their existing applications.
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
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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,
Bhoomi initiative in Karnataka
SARI (Sustainable Access for Rural India)
project of Tamilnadu
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. 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
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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).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.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
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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.
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
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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.
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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