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Introduction & history of mobile computing
1. Introduction & History of Mobile
Computing
by David J Livingston
(davidjlivingston@gmail.com)
2. What is Mobile Computing?
Mobile Computing is a technology that allows
transmission of data, voice and video via a
computer or any other wireless enabled device
without having to be connected to a fixed
physical link.
Mobile Computing is an umbrella term used to
describe technologies that enable people to
access network services anyplace, anytime, and
anywhere.
3. Define Mobility
Mobile simply describes a computing device that
is not restricted to a desktop. A mobile device
may be a PDA, a “smart” cell phone or Web
phone, a laptop computer, a tablet PC or any
one of numerous other devices that allow the
user to complete computing tasks without being
physically connected to a network.
Mobile computing does not necessarily require
wireless communication. In fact, it may not
require communication between devices at all.
4. Mobility of Bits and Bytes
In the last two centuries, mobility has been
redefined.
Both physical and virtual objects are now mobile.
- Mobility of physical objects relate to movement
of matters,
- whereas movements of virtual objects relate to
movements of bits and bytes.
5. More Definition on Mobile
Computing!
A simple definition could be:
Mobile Computing is using a computer (of one kind or another)
while on the move
Another definition could be:
Mobile Computing is when a (work) process is moved from a
normal fixed position to a more dynamic position.
A third definition could be:
Mobile Computing is when a work process is carried out
somewhere where it was not previously possible.
6. Wireless Communication
Wireless refers to the method of transferring
information between a computing device, such
as a personal data assistant (PDA), and a data
source, such as an agency database server,
without a physical connection. Not all wireless
communications technologies are mobile.
For example, lasers are used in wireless data
transfer between buildings, but cannot be used
in mobile communications at this time.
7. Wired Vs. Wireless Networks
Wired Networks
Mobile Networks
- high bandwidth
- low bandwidth
- low bandwidth variability
- high bandwidth variability
- can listen on wire
- hidden terminal problem
- high power machines
- low power machines
- high resource machines
- low resource machines
- need physical access(security)
- need proximity
- low delay
- higher delay
8. Why Mobile Computing?
Enable anywhere/anytime connectivity
Bring computer communications to areas without pre
existing infrastructure
Enable mobility
Enable new applications
An exciting new research area
10. Computer Network
A computer network is collection of several
homogeneous/heterogeneous system, commonly used for
resource sharing.
Computer networks can be classified in many ways:
Area wise:
-
LAN , MAN & WAN
As per medium used:
-
Wired Computer Network & Wireless Computer Network
11. Advantage of Wireless Networks
Flexible: Radio waves can penetrate the obstacles. Sender and
receiver can be placed any where.
Mobility: Data can be access from any location.
Robustness : Can survive in disaster (Earthquake, military
operations)
Scalable: Can be configured in variety of topologies.
Easy Installation
Less Cost
Usage of ISM band: ISM (Industrial, Scientific and Medical) band
(2.40GHz to 2.484 GHz, 5.725 GHz to 5.850 GHz) is available for
use by anyone.
No Planning: Only Wireless Ad hoc not required any planning
.
12. Disadvantage of Wireless
Networks
Quality of Service:
Lower Bandwidth
Lower Data Transmission Rate
High Error Rates
Interference
Higher Delay
Restrictions: License-free frequency bands are not same worldwide.
Safety and Security: Interference from other devices (e.g. Hospital.
Eavesdropping is possible).
13. The Beginning
Most credit Guglielmo Marconi, “the father of radio”, with the
initiation of wireless technology
1894 Marconi experimented with Hertzian Waves (radio waves) to
produce and detect waves over long distances
1896 Marconi established the Wireless Telegraph & Signal
Company, the first radio factory
1901 St John’s, New Foundland, Marconi received the first transAtlantic wireless signal from Poldhu, England
14. Evolution of Wireless Technology
1905 the first distress signal sent using Morse Code
1919 Radio Corporation of America (RCA) was incorporated, and
consumer radio broadcasts for news and entertainment soon
became popular
During World War II the US Military used wireless signals with
encryption to send battle plans and instructions
US Military started the shift to radio data transmission technology
15. The Beginning of Wireless
Technology
In 1947 researchers in AT&T Bell Labs conceived the idea of
cellular phones.
They realized that by using small service areas or cells they
can reuse the frequency.
This in turn can enhance the traffic capacity of mobile
phones.
AT&T requested the Federal Communication Commission
(FCC) to allocate a large number of radio-spectrum
frequencies so that widespread mobile telephone service
would become feasible.
16. Evolution in 20 Century
th
On October 4, 1957 the USSR (Union of Soviet Socialist Republic
now mainly Russia) launched the Sputnik. It was the first
artificial earth satellite launched from Baikonur cosmodrome in
Kazakhstan.
In response to this, the US formed the Advanced Research
Projects Agency (ARPA) within the Department of Defense
(DoD).
This laid the foundation of packet switched data networks. The
important ones are TCP /IP and X.25.
17. Evolution of Wireless Network
The first wireless network was commissioned in
Germany in 1958. It was called A-Netz and used
analog technology at 160 MHz.
Only outgoing calls were possible in this
network.That is to say that connection set-up
was possible from the mobile station only.
This system evolved into B-Netz operating at the
same 160 MHz. It was possible to receive an
incoming call from a fixed telephone network,
provided that location of the mobile station was
known.
18. Evolution of Wireless (Cont.)
A-Netz was wireless but not a cellular network.
Therefore, these systems (A-Netz and B-Netz)
did not have any function, which permitted
handover or change of base station.
In 1968, in USA, the FCC reconsidered its
position on Cellular network concept.
FCC agreed to allocate a larger frequency band
for more number of mobile phones provided the
technology to build a better mobile service be
demonstrated.
19. Cellular Technology
AT&T and Bell Labs proposed a cellular system to
the FCC with many small, low-powered,
broadcast towers, each covering a hexagonal
'cell' of a few kilometers in radius.
Collectively these cells could cover a very large
area.
Each tower would use only a few of the total
frequencies allocated to the system.
As the phones traveled across the area, calls
would be passed from tower to tower.
20. Some Inventions in Wireless
Technology
In April 1973, Martin Cooper of Motorola invented
the first mobile phone handset and made the
first call from a portable phone to Joel Engel.
By 1977, AT&T and Bell Labs constructed a
prototype of a public cellular network.
In 1978, public trials of the cellular telephony
system started in Chicago with over 2000 trial
customers.
21. First Cellular Mobile Network
In 1982, FCC finally authorized commercial
cellular service for the USA.
A year later in 1983, the first American
commercial analog cellular service AMPS
(Advanced Mobile Phone Service) was made
commercially available in Chicago.
This was the first cellular mobile network in the
world
22. Milestones in Wireless Network
TCP/IP was driven by education and defense in the USA whereas
X.25 was driven by European telecommunication industry and
Governments.
1971 network technologies met radio technologies when the first
wireless Local Area Network (LAN) was established at the
University of Hawaii during the experiment, ‘ALOHANET’
ALOHANET used a bidirectional star topology consisting of (7)
computers over (4) islands
23. Milestones (Cont.)
1973 Dr Martin Cooper, Motorola Labs, invented the first personal
mobile cellular telephone (weighed 2.5 lbs, 30 individual circuit
boards, no display screen, 9”x5”x1.75”, 10 hours to charge for
35 minutes of use)
1983 marked American entry into the commercial cellular service
market
1987 FCC allows and encourages cellular service providers to use
alternate technologies in the 800Mhz radio spectrum to prompt
use of digital transmission
24. IEEE Standard for Wirless
Networking
1990 IEEE 802 Executive Committee established the 802.11
Working Group to create a wireless LAN standard.
1997 working group approved IEEE 802.11 as the world’s first
wireless LAN standard
New standards are continuously being developed by the Institute of
Electrical and Electronical Engineers
