Download - QOD routing protocols : phase 1 ppt
QOD ROUTING PROTOCOLS
Presented by :S.Aakasham, ME-CSE
PG Scholar (2013-2015)
SVS COLLEGE OF ENGINEERING,CBE-
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Outline
Introduction of QoS Literature survey Objective Algorithm Advantages Disadvantages References
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Introduction Of QoS
To find a QoS path between source and destination, Which satisfies The QoS requirements for each admitted connection and Optimizes the use of network resources
Quality encompasses the data loss, latency, jitter, efficient use of network resources,..
QoS mechanisms for unfairness: managing queuing behavior, shaping traffic, control admission, routing, …
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Challenges In QOS
Mobility
Dynamic changing topology
Bandwidth constrains
Energy constrains
Scalability
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QOD ROUTING PROTOCOL FOR HWN
Usually, a hybrid network has widespread base stations
The data transmission in hybrid networks has two features:
1. An AP can be a source or a destination to any mobile node It allows a stream to have anycast transmission along multiple
transmission paths to its destination through base stations
2. The number of transmission hops between a mobile node and an AP is small It enables a source node to connect to an AP through an intermediate
node
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Network model of the HWM
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Algorithms
In this paper introduce the QoS-Oriented Distributed routing protocol(QOD)
This QOD protocol makes five contributions:
QoS-guaranteed neighbor selection algorithm
Distributed packet scheduling algorithm
Mobility-based segment resizing algorithm
Soft-deadline based forwarding scheduling algorithm
Data redundancy elimination based transmission
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Algorithm(cont..)
1.QoS-guaranteed neighbor selection algorithm The algorithm selects qualified neighbors and deadline-driven scheduling
mechanism to guarantee QoS routing Get an allocation set A :
Uas(i)* Wi : available workload rate source node needs to distribute its packets to the Nq
Ai : workload rate allocation from source node to immediate node Wg : the packet generating rate of the source node
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Algorithm(cont..)
2.Distributed packet scheduling algorithm After qualified neighbors are identified, this algorithm schedules packet
routing. It assigns earlier generated packets to forwarders with higher queuing delays, while assigns more recently generated packets to forwarders with lower queuing delays to reduce total transmission delay
Distributed queuing mechanism (e.g.: 3 packets distributed)
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Algorithm(cont..)
2.Distributed packet scheduling algorithm The queuing time of a packet with priority x estimated by :
and : The transmission delay and arrival interval of a packet
with the jth priority
: The number of packets arriving during the packet’s
queuing time
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Algorithm(cont..)
3.Mobility-based segment resizing algorithm The source node adaptively resizes each packet in its packet stream for each
neighbor node according to the neighbor’s mobility
The mobility of a node increases, the size of a packet Sp sent from a node to its neighbor nodes i decreases as following :
γ : Scaling parameter an
υi : The relative mobility speed of the source node and intermediate node =1 kb
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Algorithm(cont..)
4.Soft-deadline based forwarding scheduling algorithm An intermediate node first forwards the packet with the least time
allowed to wait before being packet forwarding A forwarding node can use the least slack first (LSF) scheduling
algorithm
The slack time of a packet p is defined as :
Dp : Deadline of packet p t : The current time c’ : The remaining packet transmission time of the packet
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Algorithm(cont..)
5.Data redundancy elimination based transmission The APs and mobile nodes can overhead and cache packets Use an end-to-end traffic redundancy elimination (TRE) algorithm
eliminates the redundant data to improve the QoS of the packet transmission
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Advantages
Guarantee QoS routing
Reduce total transmission delay
Increases node mobility
Achieve fairness in packet forwarding
Eliminates the redundant data
Improve the QoS of packet transmission
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