selecting transmission medium for sharing e
TRANSCRIPT
-
8/3/2019 Selecting Transmission Medium for Sharing E
1/13
Selecting Transmission Medium for sharing E-Resources:
A Comparative Study Report
R. Prabu
Ph.D. Scholar, Dept. of Library & Information Science, Bharathidasan University,
Trichy -24.
S. Ketheeswaren
Assistant Librarian, University of Jaffna, Sri Lanka
Dr. S. Srinivasa Ragavan,
Librarian and Head, Bharathidasan University, Trichy 24
Abstract
Transmission media are the physical pathways (guided or unguided) that connect
computers, other devices, and people on a network. Computers and telecommunication
devices use signals to represent data. These signals are transmitted from a device to
another in the form of electromagnetic energy. Examples of Electromagnetic energy
include power, radio waves, infrared light, visible light, ultraviolet light, and X and
gamma rays. All these electromagnetic signals constitute the electromagnetic
spectrum. Each portion of the spectrum requires a particular or unique transmission
media for the transfer of data such we call as Twisted Pair, Coaxial cable, Optical
fibber, Satellite, and Wireless etc.
In the paper, The Guided (Twisted Pair, Coaxial cable, Optical fiber) and the Unguided
Microwaves (Satellite, wifi, wimax, bluetooth) transmission mediums are compared
with help of relative plots in terms of their networking capabilities (e.g., speed,
damping length, Bandwidth, Cost and Get connection).
Optical fibber in the guided media outperforms other medias in better networking
performance but optical fibber cable connection is sensitive than twisted Pair and
Coaxial cable connections and require higher cost than the same. Twisted pair
outperforms coaxial cable. Here it is also notable that coaxial cable can be connected
easily without order, but twisted pair not like that. Among Unguided; wimax
outperforms other medias in better networking performance in long range even though
wi-fi is a substitute for providing a greater power of access than wimax in short range.
Here all unguided mediums are better for ease of access than guided.
Keywords: Transmission Medium, Guided Media, Unguided media, Data channel,
Data transfer
1
mailto:[email protected]:[email protected] -
8/3/2019 Selecting Transmission Medium for Sharing E
2/13
1. Introduction
Making an appropriate network for a service of library and information science is now
common over the world, when such network is to be established or maitained we need
much information on neworks and for chosing the appriopriate network particulary
considering library envinments, comaprative ideas of different data tansmission medias
are very essentially needed, here we make an initial step to compare different
tarasmission medias such as the Guided (Twisted Pair, Coaxial cable, Optical fiber) and
the Unguided Microwaves (Satellite, wifi, wimax, bluetooth) transmission mediums.
1.1 Data transmission medium
In order for data transmission to occur, there must be a transmission line, also called
transmission channel between the two isolated data machines.
These transmission channels are made up of several segments that allow the data tocirculate in the form of electromagnetic, electrical, light or even acoustic waves. So, in
fact, it is a vibratory phenomenon that is propagated over the physical medium.
Transmission media are the physical pathways (guided or unguided) that connect
computers, other devices, and people on a network. Computers and telecommunication
devices use signals to represent data. These signals are transmitted from a device to
another in the form of electromagnetic energy. Examples of Electromagnetic energy
include power, radio waves, infrared light, visible light, ultraviolet light, and X and
gamma rays. All these electromagnetic signals constitute the electromagnetic
spectrum. Each portion of the spectrum requires a particular or unique transmission
media for the transfer of data such we call as Twisted Pair, Coaxial cable, Opticalfibber, Satellite, and Wireless etc.
Figure 1.1.1 Electromagnetic Spectrum
2
-
8/3/2019 Selecting Transmission Medium for Sharing E
3/13
1.2 Transmission Medias
1.2.1 Guided Transmission MediaGuided Transmission Media uses a "cabling" system that guides the data signals along
a specific path. The data signals are bound by the "cabling" system.Examples
Twisted Pair (multi-pair cables), Coaxial cable, and Optical fiber
1.2.1.1 Twisted Pair (multi-pair cables)
Pair of twisted pair multi conductors
Commonly used for communication networks within library buildings and in
wired telephone networks.
Produced in unshielded (UTP) and shielded (STP) forms, and in different
performance categories as in the figure 1.2.1.1 below.
Figure 1.2.1.1.1 Twisted Pair cables in unshielded (UTP) and shielded (STP) forms
Each neighbour pairs is typically twisted to reduce crosstalk.
Figure 1.2.1.1.2 Twisted Pair Cable Connectors
3
-
8/3/2019 Selecting Transmission Medium for Sharing E
4/13
1.2.1.2 Coaxial cable
Figure 1.2.1.2.1 Cross-section of a Coaxial Cable
Offers longer damping distances than of twisted pair, due to better shielding.
Used for cable TV and local-area networks. It has been widely used in telephone
systems, but optical fiber is now assuming this task.
Figure 1.2.1.2.2 Coaxial Cable Connectors
1.2.1.3 Optical fibber
Optical Fibers are glass fibers usually about 120 micrometers in diameter that are usedto deliver wave signals in the form of pulses of light over distances up to 50 km without
the using repeaters.
Three components: light source, transmission system, and a detector
The detector generates an electric pulse when hit by light
1-a pulse of light; 0-missing pulse of light.
optical rays travel in glass or plastic core
When light move from one medium to another as below it bend at the boundary.
The amount of bending depends on the properties of the media.
4
-
8/3/2019 Selecting Transmission Medium for Sharing E
5/13
Light at shallow angles propagate along the fibre, and those that are less than
critical angle are absorbed in the jacket
The cladding is a glass or plastic with properties that differ from those of the
core
Not affected by external electromagnetic fields, and do not radiate energy.
Hence, providing high degree of security from eavesdropping.
Reduction of the radius of the core implies less reflected angles. Single mode is
achieved with sufficient small radius.
Figure 1.2.1.3.1 Optical Fibre Cable Connectors
1.2.2 Unguided Transmission MediaUnguided Transmission Media now consists of a means for the data signals to travel
but nothing to guide them along a specific path. The data signals are not bound to a
cabling media and as such are often called Unbound Media.
Examples: Wi-Fi, Wimax, Bluetooth, and Satellite
1.2.2.1 Wi-Fi
The name Wi-Fi (short for "Wireless Fidelity", sometimes incorrectly shortened
to WiFi) corresponds to the name of the certification given by the Wi-Fi
Alliance, formerly WECA (Wireless Ethernet Compatibility Alliance).
With Wi-Fi, it is possible to create high-speed wireless local area networks,
provided that the computer to be connected is not too far from the access point.
In practice, Wi-Fi can be used to provide high-speed connections (11 Mbps or
greater) to laptop computers, desktop computers, personal digital assistants
(PDAs) and any other devices located within a radius of several dozen metres
5
-
8/3/2019 Selecting Transmission Medium for Sharing E
6/13
indoors (in general 20m-50m away) or within several hundred metres outdoors.
Figure 1.2.2.1.1 A sample Wi-Fi network in Library Buildings
Wi-Fi providers are starting to blanket areas that have a high concentration of
users (like train stations, airports, and hotels) with wireless networks. These
access areas are called "hot spots"
1.2.2.2 Wimax
What is WiMAX:
WiMAX is a short name for Worldwide Interoperability of Microwave Access.
WiMAX is described in IEEE 802.16 Wireless Metropolitan Area Network (MAN)
standard. It is expected that WiMAX compliant systems will provide fixed wireless
alternative to conventional Cable Internet.
Typically, a WiMAX system consists of two parts:
A WiMAX Base Station: Base station consists of indoor electronic systems
and a WiMAX tower. Typically, a base station can cover up to 10 km radius
(Theoretically, a base station can cover up to 50 kilo meter radius or 30 miles,
however practical considerations limit it to about 10 km or 6 miles). Anywireless node within the coverage area would be able to access the Internet.
A WiMAX receiver - The receiver and antenna could be a stand-alone box or a
PCMCIA card that sits inside the laptop or computer. Access to WiMAX base
station is similar to accessing a Wireless Access Point in a WiFi network, but
the coverage is more.
Important Wireless MAN IEEE 802.16 (WiMAX) Specifications
Range - 30-mile (50-km) radius from base station
Speed - Up to 70 megabits per second
Non-Line-of-sight (NLoS) between user and base station
6
-
8/3/2019 Selecting Transmission Medium for Sharing E
7/13
Frequency bands - 2 to 11 GHz and 10 to 66 GHz (licensed and unlicensed bands)
Figure 1.2.2.2.1 A sample Wimax network
1.2.2.3 BluetoothBluetooth is a short range, wire free, secure and international standardized wireless
technology that provides wireless communication system between the Bluetooth
enabled devices in a short ranged network. Bluetooth technology is a short range
wireless technology that was developed by the collaboration of mobile phones and IT
companies such as Nokia, Intel, Toshiba, Erickson and IBM. Bluetooth develops short
range wireless connections between the laptops, handheld pcs, wireless communication
devices and mobile phones. Bluetooth is only available to the personal area networks in
an office or a home network.
It reduces the usage of power as compared to the Wi-Fi. Bluetooth is an international
standardized technology that is used for the wireless communication between the
Bluetooth held devices such as mobile phones, digital camera, laptops, desktop
computers, keyboard, mouse, mp3 players, video cameras and other devices
Bluetooth uses radio waves frequency as a medium and is suitable for the 1, 10 and 100
meters distance. Like the Bluetooth, Wi-Fi uses the same frequency but the power
consumption of the wi-fi is high so it produces more powerful signals
Bluetooth uses radio waves that operate at 2.4 GHz bands. Microsoft Windows XP withthe service pack 2 has the built-in support for the Bluetooth technology. The master
Bluetooth device can communication with the seven other Bluetooth enabled devices.
Different devices support different standards of the Bluetooth technology. The research
on the advanced Bluetooth is in progress for the Bluetooth version 3.0 to provide the
high-speed connections.
1.2.2.4 SatelliteIn 1962, the American telecommunications giant AT&T launched the world's first true
communications satellite, called Telstar. Since then, countless communications
satellites have been placed into earth orbit, and the technology being applied to them is
forever growing in sophistication
7
-
8/3/2019 Selecting Transmission Medium for Sharing E
8/13
1.2.2.4.1 Basic Elements
Satellite communications are comprised of following 2 main components:
1.2.2.4.1.1 The Satellite
The satellite itself also known as the space segment, and is composed of three separate
units, namely the fuel system, the satellite and telemetry controls, and the transponder.
The transponder includes the receiving antenna to pick-up signals from the groundstation, a broad band receiver, an input multiplexer, and a frequency converter which is
used to reroute the received signals through a high powered amplifier for downlink.
The primary role of a satellite is to reflect electronic signals. In the case of a telecom
satellite, the primary task is to receive signals from a ground station and send them
down to another ground station located a considerable distance away from the first.
This relay action can be two-way, as in the case of a long distance phone call. Another
use of the satellite is when, as is the case with television broadcasts and internet, the
ground station's uplink is down linked over a wide region, so that many different
customers possessing compatible equipment may receive it. Still another use for
satellites is observation, wherein the satellite is equipped with cameras or various
sensors, and it merely downlinks any information it picks up from its vantagepoint. l
1.2.2.4.1.2 The Ground Station.
This is the earth segment. The ground station's job is two-fold. In the case of an uplink,
or transmitting station, terrestrial data in the form of base band signals, is passed
through a base band processor, an up converter, a high powered amplifier, and through
a parabolic dish antenna up to an orbiting satellite. In the case of a downlink, or
receiving station, works in the reverse fashion as the uplink, ultimately converting
signals received through the parabolic antenna to base band signal
Figure 1.2.2.4.1 Network made up with satellite signals
8
-
8/3/2019 Selecting Transmission Medium for Sharing E
9/13
2. Tools and works of Comparative Performance
Definitions to the Key terms used in comparative Performance2.1 Damping Length
The length where an amplifier or repeater is needed to further propagate the data signalwithout the data loss and noise
2.2 Maximum Speed of Data Transfer
The optimal rate of data transfer at which the data possibly being propagated through a
Transmission medium in bit per second
2.3 BandwidthThe maximum amount of information that can be transferred over a network in a given
amount of time; when multiple devices are connected to the network, the bandwidth is
divided, depleting transfer rates and decreasing overall network reliability.
2.4 CostCost means the comparative ranks given to each media according to their basic network
implementing cost. Higher rank is given to a media for which the basic network
implementing cost becomes high.
2.5 Get Connection
Getting connection means the comparative ranks given to each media according to the
toughness for becoming networked. Higher rank is given to a media for which the
toughness becomes high.
3. Data CollectionsFor getting the current information on maximum speed, damping length, Bandwidth
which are assumed to important tools for evaluating the transmission medias the
relevant authenticated websites were searched for achieving data on maximum speed,
damping length, Bandwidth of each transmission medias with applied latest modern
technologies. The reference in the annex shows the URL on which the useful
information on such data taken.
4. Test environmentThe collected data vary even among a transmission media with different applied
modern technologies. After collecting the data, the data were reviewed for gettingmaximum permissible values on speed, damping length, Bandwidth for each
transmission media with an applied modern technology for easily comparing each other
transmission medium with a unique value. The values found for satellite extreme
higher than the other media, so it was neglected in comparison.
9
-
8/3/2019 Selecting Transmission Medium for Sharing E
10/13
Mediums Damping Length Max speed Bandwidth Cost Get connected
Guided
Twisted pair
(multi-pair cables) 2 Km 100 Mbps 300 MHz Little High (rank 3)
Systematic Care needed
(rank 2)
Coaxial cable 9 Km 40 Mbps 35 MHz Medium (rank 4) Care needed (rank 3)
Optical fibber 60 Km 2.4 Gbps 2 GHz Very High (rank 1) Little tough (rank 1)
Ung
uidedWi-Fi 50 M (indoor) 54 Mbps 5 GHz High (rank 2) Easy (rank 4)
Wimax 10 Km (practically) 70 Mbps 11 GHz High (rank2) Easy (rank 4)
Bluetooth 10 M 0.72 Mbps 2.5 GHZ Low (rank 5) Very Easy (rank 5)Satellite 30000 Km 1.2 Gbps 60 GHz Extreme high Minute and tough
Relative percentage
Guided
Twisted pair
(multi-pair cables) 3.33 4.07 1.50 60.00 40.00
Coaxial cable 15.00 1.63 0.18 80.00 60.00
Optical fiber 100.00 100.00 100.00 20.00 20.00
UnguidedWi-Fi 0.08 2.20 25.00 40.00 80.00
Wimax 16.67 2.85 55.00 40.00 80.00
Bluetooth 0.02 0.03 12.50 100.00 100.00
Satellite Omitted as comparably very high valules
5. Table of Data Collections and plots
10
-
8/3/2019 Selecting Transmission Medium for Sharing E
11/13
11
0
10
20
30
40
50
60
Damping Length (Km)
0
500
1000
1500
2000
2500
Max speed (Mbps)
Twisted
pair
(multi-
pair
cables)
Coaxial
cable
Optical
fiberWi-Fi Wimax Bluetooth
0
20004000
6000
8000
10000
12000
14000
16000
18000
20000
Bandwidth (MHz)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Cost (Rank)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Get connected (Rank)
e at ve ercentages s e ecte e u
.00
.
0.00
0.00
.00
0.00
20.00
Twisted pair
-
Coaxial cable Optical fiber Wi-Fi Wimax Blue
Damping Length
Bandwidth
Cost
Get connected
6. Charts: Comparing Transmission Medias
-
8/3/2019 Selecting Transmission Medium for Sharing E
12/13
7. Result and Discussion
From charts in the paper, we see optical fibber posses the grater stages in
speed, damping length and bandwidth but optical fibber cable connection is
sensitive than twisted Pair and Coaxial cable connections and require highercost that the same.
Even coaxial cabling system has higher damping length than twisted pair
system; twisted pair has higher bandwidth and speed, so we can say twisted
pair outperforms coaxial cable. Here it is also notable that coaxial cable can be
connected easily without order, but twisted pair not like that.
Here we see from the charts, all unguided mediums are better for ease of
access than guided. Among Unguided; wimax outperforms other Medias in
better networking performance in long range (speed, damping length and
bandwidth), even though wi-fi is a substitute for providing a greater power of
access than wimax in short range. Even satellite performs with higher values
of speed, damping length and bandwidth, the implementing cost and minuteconnection control get demerits, so we do not choose satellite as an populated
outperforming media device for networking compared to other medias.
8. Findings Optical fibber in the guided media outperforms other Medias in better
networking performance but optical fibber cable connection is sensitive than
twisted Pair and Coaxial cable connections and require higher cost that the
same.
Twisted pair outperforms coaxial cable. Here it is also notable that coaxial
cable can be connected easily without order, but twisted pair not like that. Among Unguided; wimax outperforms other Medias in better networking
performance in long range even though wi-fi is a substitute for providing a
greater power of access than wimax in short range.
Here all unguided mediums are better for ease of access than guided.
9. References
http://www.crutchfield.com/SLu3lQkqk5S/Learn/learningcenter/home/wireles
s_glossary.html#rate for introductory text and reviews Last accessed on 12
January 2009 http://www.crutchfield.com/Learn/learningcenter/home/bluetooth.html for
bluetooth Last Accessed on 15 January 2009
http://www.rfdesign.info/doc-desc/18/WiMAX-An-Introduction.html for
wimax, wi-fi and Bluetooth Last Accessed on 20th January 2009
http://searchmobilecomputing.techtarget.com/tip/0,289483,sid40_gci970933,0
0.html for wimax Last accessed on 26th January 2009
http://www.wtec.org/loyola/satcom/c2_s3.htm#f2_30 for satellite
Last accessed on 2nd February 2009
http://www.rap.ucar.edu/~djohnson/satellite/coverage.html for staellite
Last accessed on 5th February 2009
12
http://www.crutchfield.com/SL%EF%82%A7%09http:/www.crutchfield.com/SLu3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html#rate%20for%20introductory%20text%20au3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html%23rate%20for%20introductory%20text%20and%20reviewshttp://www.crutchfield.com/SL%EF%82%A7%09http:/www.crutchfield.com/SLu3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html#rate%20for%20introductory%20text%20au3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html%23rate%20for%20introductory%20text%20and%20reviewshttp://www.crutchfield.com/Learn/learningcenter/home/bluetooth.htmlhttp://www.crutchfield.com/Learn/learningcenter/home/bluetooth.htmlhttp://www.rfdesign.info/doc-desc/18/WiMAX-An-Introduction.htmlhttp://www.rfdesign.info/doc-desc/18/WiMAX-An-Introduction.htmlhttp://searchmobilecomputing.techtarget.com/tip/0,289483,sid40_gci970933,00.htmlhttp://searchmobilecomputing.techtarget.com/tip/0,289483,sid40_gci970933,00.htmlhttp://www.wtec.org/loyola/satco%EF%82%A7%09http:/www.wtec.org/loyola/satcom/c2_s3.htm#f2_30%20for%20satellite%20m/c2_s3.htmhttp://www.rap.ucar.edu/~djohnson/satellite/coverage.html%20for%20staellitehttp://www.crutchfield.com/SL%EF%82%A7%09http:/www.crutchfield.com/SLu3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html#rate%20for%20introductory%20text%20au3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html%23rate%20for%20introductory%20text%20and%20reviewshttp://www.crutchfield.com/SL%EF%82%A7%09http:/www.crutchfield.com/SLu3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html#rate%20for%20introductory%20text%20au3lQkqk5S/Learn/learningcenter/home/wireless_glossary.html%23rate%20for%20introductory%20text%20and%20reviewshttp://www.crutchfield.com/Learn/learningcenter/home/bluetooth.htmlhttp://www.crutchfield.com/Learn/learningcenter/home/bluetooth.htmlhttp://www.rfdesign.info/doc-desc/18/WiMAX-An-Introduction.htmlhttp://www.rfdesign.info/doc-desc/18/WiMAX-An-Introduction.htmlhttp://searchmobilecomputing.techtarget.com/tip/0,289483,sid40_gci970933,00.htmlhttp://searchmobilecomputing.techtarget.com/tip/0,289483,sid40_gci970933,00.htmlhttp://www.wtec.org/loyola/satco%EF%82%A7%09http:/www.wtec.org/loyola/satcom/c2_s3.htm#f2_30%20for%20satellite%20m/c2_s3.htmhttp://www.rap.ucar.edu/~djohnson/satellite/coverage.html%20for%20staellite -
8/3/2019 Selecting Transmission Medium for Sharing E
13/13
www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.ppt for
fundamentals of satellite communication
Last accessed on 12th February 2009
http://en.wikipedia.org/wiki/Transmission_medium for introduction
Last accessed on 29 December 2008
http://en.kioskea.net/contents/transmission/transintro.php3 for introductionLast accessed on 15th March 2009
http://www.britannica.com/ebchecked/topic/524891/statellite- communication
Last accessed on 17th April 2009.
13
http://opt/scribd/conversion/tmp/scratch6899/?www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.pptfor%20fundamentals%20of%20satellite%20communicationhttp:/www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.ppthttp://opt/scribd/conversion/tmp/scratch6899/?www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.pptfor%20fundamentals%20of%20satellite%20communicationhttp:/www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.ppthttp://opt/scribd/conversion/tmp/scratch6899/?www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.pptfor%20fundamentals%20of%20satellite%20communicationhttp:/www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.ppthttp://opt/scribd/conversion/tmp/scratch6899/?www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.pptfor%20fundamentals%20of%20satellite%20communicationhttp:/www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.ppthttp://en.wikipedia.org/wiki/Transmission_m%EF%82%A7%09http:/en.wikipedia.org/wiki/Transmission_medium%20for%20introduction%20%20ediumhttp://opt/scribd/conversion/tmp/scratch6899/http?http:/en.kioskea.net/contents/transmission/transintro.php3%20for%20introduction:/en.kioskea.net/contents/transmission/transintro.php3http://www.britannica.com/ebchecked/topic/524891/statellite-http://communiationttp//www.britannica.com/ebchecked/topic/524891/statellite-communiationhttp://opt/scribd/conversion/tmp/scratch6899/?www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.pptfor%20fundamentals%20of%20satellite%20communicationhttp:/www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.ppthttp://opt/scribd/conversion/tmp/scratch6899/?www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.pptfor%20fundamentals%20of%20satellite%20communicationhttp:/www.bsu.edu/web/ebleech/ppt/wk10_Satellite___Microwave.ppthttp://en.wikipedia.org/wiki/Transmission_m%EF%82%A7%09http:/en.wikipedia.org/wiki/Transmission_medium%20for%20introduction%20%20ediumhttp://opt/scribd/conversion/tmp/scratch6899/http?http:/en.kioskea.net/contents/transmission/transintro.php3%20for%20introduction:/en.kioskea.net/contents/transmission/transintro.php3http://www.britannica.com/ebchecked/topic/524891/statellite-http://communiationttp//www.britannica.com/ebchecked/topic/524891/statellite-communiation