Wireless Networking Additional Slides.ppt

Basics of Wireless Networks

1. Chapter2
BasicsofWireless
Networks
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

2. Learning objectives

To
understand wireless networks
 Toknow the access technologies
 Tostudy problems such as interference,multi-path
propagation, path loss, battery life, etc.
 Toillustrate issues like channel allocation,routing,
mobility, security, power management,
etc.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

3. Wireless networks
Wired network
 Wire as communication
 High data rate
 No mobility
medium
Wireless network
 Radio waves and
 Less data rate
 Highly portable
 Mobility
airasamedium
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

4. Wireless networks(Contd..)
 Provide
Internet
inexpensiveandrapid connection setupwith
 Restricted by distance

Overlapping
radiocellstoprovideconnectivity
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

5. Wirelessnetworkarchitecture
Itconsistsofmobilehosts,fixedhosts,accessstations(BS),
core network to support mobility and switching.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

6. Wireless network architecture (Contd..)
Mobile host
 Laptop, mobile phone,PDA, notebook, etc. can
movefrom oneplacetoanotherplacewhile
maintaining connectionwith wireless network.
Fixed wireless host
 Cannot move but the medium is radio waves.
 Example: wireless web servers, printers, etc.
Access Network
 Consistsofaccessstations(BS)whichprovide
services to hosts reachable from it.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

7. Wireless network architecture (Contd..)
Core Network
 Consistsofactivecomponents thatperform
data switching between accessstations(BS),
and provide location and mobility services.
 Facilitates communication from mobile host to
mobilehost,mobilehost
fixed
towirednode,fixed
host,host
etc.
towirednode, hosttomobile
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

8. Classification of wirelessnetworks
 Wireless
 Wireless
 Wireless
 Wireless
 Wireless
body area networks
personal area networks
local area networks
metropolitan area networks
wide area networks such as
and
GSM or
CDMA cellular networks
 Satellite networks and
broadband
access networks
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

9. Classification of wireless
(Contd..)
networks
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

10. Classification of wireless
(Contd..)
Wireless Body Area Network (WBAN)
networks
 Max. signal range 2 meters
 Interconnectingrespectivedeviceswithinthesurfaceofthebody



These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

11. Classification of wireless
(Contd..)
networks
WirelessBodyAreaNetwork(WBAN)
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

12. Classification of wireless
(Contd..)
networks
Wireless Personal Area Network(WPAN)
 Max.signalrangeof10meters
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

13. Classification of wireless networks
(Contd..)
Wireless Local Area Network (WLAN)
• Signal range is ≈100 meters.
• AlsocalledtheWirelessFidelity(Wi-FiorIEEE802.11)
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

14. Recall:anexample ofwiredLAN
Station
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.
Work
PrinterServer
Laptop
Work
Station
LaptopLaptop
Work
Station

15. AnexampleofwirelessLAN
A user is connected if
he/she is in the coverage
area of a cell
Each cell operates at a
different frequency
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.
Work
Station
Work
Station
Work
Station
Work
Station
Work
Station
PrinterServer
Access
Point
Access
Point
Access
Point
Access
Point
Access
Point
Access
Point
Laptop
Laptop
LaptopLaptopLaptop
Work
Station

16. Classification of wireless networks
(Contd..)
Wireless Metropolitan Area Network (WMAN)
 Signal range of approximately 5 km to 20 km (recently up to 50
km) OftencalledWorldwideInteroperabilityforMicrowaveAccess
(WiMAXorIEEE802.16)
Wi-Fi users
may be
connected to
the WiMAX
network
WiMAX BS
Mobile devices
might have
built in WiMAX
adapter or may
be externally
plugged
WMAN might
be owned and
operated by
organizations
or public
institutions
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

17. Classification of wireless networks
(Contd..)
Wireless Wide Area Network (WWAN)
 Use network infrastructure of mobile operators.
 Cover wide area much wider than groups mentioned above.
 Use cellular networktechnologiessuchasWI-MAX,GSM,GPRS,
3Gandothers.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

18. Wireless switching technology
Packet switching is the basic type of
technology
 Uses short bursts of information,
wireless switching
useschannelsonly
for short periodsof time.
protocols. Standardrouting
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

19. Recall:Packetswitching
2
nd
From W. Stallings, Wireless Communications and Networks,Edition
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

20. Recall:Packetswitching(Contd..)
From W. Stallings, Wireless Communications and Networks, 2
nd Edition
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

21. Wirelessswitchingtechnology(Contd..)
- Packets are routed and pipelined using multiplexing
- Bandwidth is used only when data is transmitted
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

22. Wireless switching technology(Contd..)
Virtual circuit
 Switched virtual circuits (SVCs)
 Established dynamically on demand
 3 phases – circuit establishment,
termination
datatransfer,circuit
 Permanent virtual
circuits
(PVCs)
transfer Onlyonemodei.e.,data
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

23. Wireless communication
 Increased bit error rate
 Lower transmission power
 Scattering
 Reflection
 Diffraction
problems
 Multipathpropagation
 Pathloss
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

24. Wireless communication problems
Increased bit error rate
Wireless network media is more prone to
 obstacles between Tx and Rx
 Interference from neighbour nodes
One can observe
errorsdueto
 Frequent disconnections causing to dataloss
 Annoyingtovoiceandvideoclients
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

25. Wireless communication problems (Contd..)
Lower transmission power
 Mobile units powered by battery have scarce energy resources
 Limited transmission power to avoid interference
 Attenuation
Capture power at the receiver side is P
r
= P
t
/ (4 πd / l)
2
Where P
t is the transmitter power, d the distance between
and the receiver, and l is the wavelength of the signal.
L
p = (4 πd / l)
2
is the path loss.
Scattering
the transmitter
 Occurs whensignalpassthroughtheobjectwhosedimensionis
smaller than the wavelength.
 Scatteredwavesareproducedbyrough surfaces,smallobjects,
irregularities in the channel. Need
reduce it.
proper deployment strategies to
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

26. Wireless communication problems
(Contd..)
Reflection
 Occurs when electromagnetic wave strikes an object which has
very large dimension compared to the wave length. Ex: walls,
furniture,
buildings, etc.
Diffraction
 Occurs when radio path between Tx and Rx is obstructed by surfaces
that
will
have sharp irregularities (edges) causing secondarywaves,which
bepresentinspaceandbehindtheobstacle.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

27. Wireless communication problems
(Contd..)
Multipath Propagation
 Caused by reflection and scattering
 Radio waves arrive at the Rx from different
delays
 Final signal is the summation of all signals
directions with varying
 Antenna diversity
methods
areusedtoovercomethisproblem
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

28. Wireless network reference model
 The
OSI
TCP/IP architectureisfunctionallyequivalenttothe
referencemodel.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

29. Recall:TCP/IPConcepts
2
nd
From W. Stallings, Wireless Communications and Networks,Edition
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

30. ProtocolDataUnitsintheTCP/IP
Architecture
Examples:
TCP header includes destination port, sequence number,checksum
IP header includes destination host address (B in previous example)
Network header includes destination subnetwork address
From W. Stallings, Wireless Communications and Networks, 2
nd Edition
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

31. Wireless network reference model
(Contd..)
 Majorsimilarities anddifferences between
TCP/IP and the OSI reference models are
 Bothmodelshaveanapplication,a
transport, anda network/Internet layer
 TheTCP/IPmodeldoesnothavea
session layer
 Lowerlayersconnectstheupperlayers
to the actual physical network
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

32. Wireless network reference model
(Contd..)
 Application layer functions
 This is the layer where end user applications such as remote
login,
mail transfer, file transfer, network management, and web
browsers
run
 Transport layer functions
 Itsjobistoprovidereliablecommunicationfromapplicationto
application (end-to-end) regardless of
communication links
 It encapsulates
application layer data layer
the lower-layer protocols and
and deliver it to the network
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

33. Illustrationofthetransportservice
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

34. Wireless network reference model
(Contd..)
 Data link layer functions
 This includes the logical link control (LLC) sublayer and
MAC (media access control) sublayer.
the
 It does segmenting the bit stream into frames, error handling,
flow control, and access control.
 MAC is
channel
responsible
and reliable
for accessing and sharing of the wireless
delivery by using acknowledgments.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.

35. Illustrationof datalinklayer
Bridge
802.4LLC P
802.4 LLC P
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.
802802.3LLC
P
LLC
P
802.3 LLC P
8024LLC P
802.3 LLC P 802
Computer A
P
LLC P
802.3 LLC P
802.3LLC P
Computer B
P
LLC P
802.4 LLC P
802.4 LLC
P

36. Wireless network reference model
(Contd..)
 Physical layer functions
 This layer transports encapsulated data from the data link
transmits it wirelessly to the distant network.
layerand
 The wireless features and functionality(modulationtype,data rate,
andsoon)takeplaceatthislayer.
These slides are based on the slides formatted by Dr Sunilkumar S. manvi and Dr Mahabaleshwar S. Kakkasageri,
the authors of the textbook: Wireless and Mobile Networks, concepts and protocols. See slide number one.