LYU9903 QoS Schemes in Wireless Networks

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LYU9903QoS Schemes in Wireless Networks

• Ho Pun Mo Matchman
• Ng Maggie
• Supervised by Prof. Michael Lyu

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Outline

• What is Wireless LAN?
• Why Wireless?
• How to Wireless?
• Examples of Wireless device
• Applications of Wireless LAN
• Advantages and Disadvantages of Wireless LAN
• What is QoS
• Why QoS is needed in Wireless?
• QoS Schmemes
• Application for QoS Scheme
• Measurement of QoS Scheme
• Future work

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1 What is Wireless LAN?

• A flexible data communications system
• As an extension to/alternative for wired LAN
• Using radio frequency (RF) technologies
• Transmit and receive data over the air

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2 Why Wireless?

• Mobility
• Installation speed and simplicity
• Installation flexibility
• Reduced cost-of-ownership
• Scalability

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3 How to Wireless?

• Equipment needed
• Configuration

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3.1 Equipment needed

• Access Points
• Adapter cards

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3.2.1 Configuration - Peer-to-peer

• A peer-to-peer network
• Access to resources of each other, but not a
  central server

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3.2.2 Configuration
- An Access Point

• Extend the range of an ad hoc network
• Doubling range at which the devices can
  communicate
• Access to resources of both server and clients

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3.2.3 Configuration - Multiple Access Points

• Blanket the coverage area with overlapping cells
• Enable roaming

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4 Examples of Wireless Device
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5 Applications of Wireless LAN

• Health Care
• Education and Research
• Restaurant and Retail
• Warehousing
• Trading and Banking
• Consulting and Sales

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6 Advantages Disadvantages of Wireless LAN

• Advantages
• Inexpensive
• Have enough bandwidth to handle office tasks
• Do well in roaming
• Flexible
• Easy to install

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6 Advantages Disadvantages of Wireless LAN

• Disadvantages
• Small bandwidth causes problems with multimedia
  transmission
• Limit number of connected nodes
• Limit range of coverage
• Large battery consumptions
• For infrared, line-of-sight may be needed

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7 What is QoS?

• QoS is the collective effect of service
  performances which determine the degree of
  satisfaction of a user of the service.
• QoS is the guarantee a network makes to an
  application in terms of providing a certain
  contracted level of service through out the
  application session.
• QoS represents quantities like how fast can data
  be transferred, how much does the receiver have
  to wait, how correct is the received data likely
  to be, how much data is likely to be lost, etc.
• ATM defines QoS as a collection of rate, latency,
  jitter loss ratio and error ratio.
• QoS refers to the ability of a network to deliver
  time-bounded traffic types (e.g., realtime video
  or voice) with predictable latencies.

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8 Why QoS is needed in Wireless?

• Growth of real-time multimedia applications
• Wireless to be a trend

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9 QoS Schemes

• Architecture
• Implementation

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9.1 Architecture

• A working network
• Bandwidth reservation mechanism
• Packet scheduling algorithm
• Packet classifier

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9.2.1 Implementation - RSVP

• ReSerVation Protocol
• Reserving bandwidth along the path
• Works with both IPv4 and IPv6

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9.2.2 Implementation - Packet
Scheduler

• FIFO
• RED
• CSZ
• SFQ
• TBF
• TFQL
• PRIO
• CBQ

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10 Application for QoS Scheme

• MP3 player for demonstrating the use of QoS.

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10 Application for QoS Scheme

• Interface of MP3 player

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11 Measurement of QoS Scheme
No Qos
Qos
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11 Measurement of QoS Scheme
Qos
No Qos
Compare the performance of transmitting FTP MP3
by using Proxim.
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12 Future Work

• Implementing Video on Demand in Wireless LAN
• Measure the QoS of VOD

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THE END

• Thank you!