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Unbounded Network Media
 Wireless Networking
 Wireless Network Devices and Components
 Install a Wireless Network
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 1
OSI Model Location
7
Application
6
Presentation
5
Session
4
Transport
3
Network
2
Data Link
1
Physical
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 2
Wireless Communication
Signals are transmitted
over a distance without
the use of a physical
medium
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 3
The IEEE 802.11 Standard
Standard
Speed (Mbps)
Frequency
(Ghz)
Range
(meters)
MIMO Streams
802.11a
54
5
20
1
802.11ac
433/channel
5
35
8
802.11b
11
2.4
100
1
802.11g
54
2.4
100
1
802.11n
150
2.4 or 5
70
4
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 4
Frequencies and Overlap of Wireless Channels
1
2
3
4
5
6
7
8
9
10
11
12
13
2.412 2.417 2.422 2.427 2.432 2.437 2.442 2.447 2.452 2.457 2.462 2.467 2.472
Copyright © 2015 Logical Operations, Inc. All rights reserved.
14
Channel
2.484 Center Frequency
(GHz)
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Radio Networking
Signals are sent
via RF waves
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 6
Broadcast Radio
Non-directional single
frequency transmission
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OV 3 - 7
Spread Spectrum
Signal is sent
over more than
one frequency
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OV 3 - 8
Types of Spread Spectrum
 OFDM
 DSSS
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 9
Infrared Transmission
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Signals sent as infrared light pulses.
Transmit at 300 GHz to 300,000 GHz.
Receiver needs unobstructed view of sender.
Signal can reflect off hard surfaces.
Used for:
 Remote control systems.
 Security sensors.
 Manufacturing sensors.
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 10
Bluetooth
30 meters
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OV 3 - 11
Microwave Transmission
Sender transmits
electromagnetic signals
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Receiver has an
unobstructed view
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Wireless Access Points
Device that provides a connection
between wireless devices
WAP
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 13
Wireless Controllers
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Provide wireless LAN management for multiple access points.
Used in combination with the LWAPP.
Can be a physical device or a software application.
LWAPP is a protocol that controls multiple Wi-Fi wireless access points.
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 14
Wireless Bridges
Receives signal from
wireless router and provides
connection to wired devices
Wireless
Router
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Wireless
Bridge
OV 3 - 15
Wireless Antennas
Wireless Tower
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Dish Antenna
OV 3 - 16
Wireless Antenna Types
Directional Antenna
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Omni-directional
Antenna
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Wireless Antenna Performance Factors
 Infrared:
 Sunlight
 Obstacles
 Smoke, dust, fog
 Radio:
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Antenna signal characteristics
Wire mesh in walls, thick walls
Ambient electrical noise
Conductive obstacles
Other electrical equipment
Data transmission rate
 Microwave:
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Weather
Antenna signal characteristics
Line of sight
Distance between transmitting stations
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 18
WLAN Overview
Client
systems
Wireless
connectivity device
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 19
WLAN Architecture
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STA
AP
Service sets
BSS and BSSID
ESS and ESSID
IBSS
DS
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 20
802.11 Modes
Infrastructure mode
ESS
Distributed
System
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OV 3 - 21
802.11 Modes (Cont.)
Ad-hoc mode
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OV 3 - 22
SSID Broadcasts
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Continuous announcement by WAP.
Transmits its name (SSID).
Often referred to as a beacon.
If a WAP is password-protected, devices can see it but not connect to it.
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 23
Mobile Devices
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Mobile phone
Laptop
Tablet
Gaming device
Media device
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 24
Guidelines for Implementing
a Basic Wireless Network
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Create a list of requirements.
Consider devices and how they meet your requirements.
Consider environmental limitations.
Consider equipment limitations.
Consider compatibility requirements.
Choose appropriate 802.11 technology.
Choose appropriate AP placement locations.
Install APs.
Test after installation:
 Appropriately sized
 Secure
 Operational
 Document steps and establish a baseline.
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 25
Reflective Questions
1. In your opinion, what are the primary considerations for implementing a
wireless network?
2. What problems have you encountered when setting up a wireless network?
Copyright © 2015 Logical Operations, Inc. All rights reserved.
OV 3 - 26