PAC: Perceptive Admission Control for Mobile Wireless Networks

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PAC Perceptive Admission Control for Mobile
Wireless Networks

• Ian D. Chakeres
• Elizabeth M. Belding-Royer

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Goal

• Control the amount of traffic in the network
• Provide high quality service to all admitted
  traffic
• Ensure the network congestion point is not
  reached

3
Background Impacted area
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Background Receiver is also a sender

• CSRgtRIDgtRxR

5
Background

• How is RID defined?
• When two packets are transmitted simultaneously,
  the signal power of one must be great then
  another by some capture factor (10)
• The signal strength of any other transmission can
  not be greater than RXTresh/10

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Background

• The safe distance between two senders is 2RxRRID

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Perceptive Admission Control

• Nodes determine the available bandwidth on their
  own
• No query flooding is needed
• Change the CSR to 2RxRRID
• Can determine accurate available bandwidth
  without sending query messages
• A sender can detect the possible impact of
  creating a new traffic

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Determining the Available Bandwidth

• MAC Layer Congestion Window
• Queue Length
• Number of Collision
• Delay
• Channel Busy Time
• Transmitting
• Receiving
• Busy

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Perceptive Admission Control
New CSR

• A sender can consider only the traffic within
  this new CSR before admitting a new traffic

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Contention-Aware Admission Control Protocol
(CACP) V.S. PAC
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Query flooding may fail

• S2 is an isolated node, but it does affected by
  the new traffic brought by S1
• Solution use high power packet transmission to
  send the query message

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Mobility

• What would happen if two sender-receiver pairs
  move closer than the safe range

?
75
75
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Mobility

• Each source monitors the available bandwidth
• Senders check available bandwidth after a random
  time and before sending a packet
• Random back-off time

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Simulation Result
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Simulation Result
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Simulation Result

• PAC does not send query message, thus reduce the
  query overhead.

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Conclusion

• PAC effectively limits the amount of data traffic
  to avoid congestion
• Provides consistent throughput, low packet loss
  and delay
• Useful in wireless application that requires high
  QoS such as multimedia applications