Hop State Prediction Method using
Distance Differential of RSSI on VANET
指導教授：許子衡 教授
報告學生：董藝興 學生
作者：Won Seok Choi ; Jong Wook Nam ; Seong Gon Choi ;
出處：Networked Computing and Advanced Information
Management, 2008. NCM '08. Fourth International
Conference on
1
Introduction
• In VANET, each hops can dynamically
move and it can move at high speed.
• So, the optimized routing protocol is
required in VANET.
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Introduction
• By using the speed, using RSSI a distance,
and the factors, this protocol predicts the
link destruction possibility of the inbetween hop.
• By finding the first the amount of change,
and the second the amount of change the
range change that it is periodic can be
found.
3
Introduction
• It is the proactive protocol which it makes
the new link before a link is destroyed by
this prediction and prevents the link break
down.
• If the Proactive protocol is not used, a
communication is unable to be smoothly
made while the new link is produced after
a link is destroyed.
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Related works
• However, in VANET, the network
disconnection is the main factor of the
emergency message propagation time delay
and network connectivity degradation.
• Therefore, the excel routing protocol is
required.
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Related works
• The major focus of VANET :
• Safety and non-safety applications
• Roadside-to-vehicle and vehicle-to-vehicle
communication
• Communication protocol design
• Channel modeling
• Modulation and coding
• Power control and scalability issues
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Related works
• Reactive Routing Protocols in VANET :
Traditionally, reactive protocols do not take
into account mobility parameters during
route discovery, resulting in paths which
often break in highly mobile scenarios such
as VANETs, causing excessive broadcasting
and flooding the entire network in order
for new routes to be discovered.
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Related works
• Furthermore, the additional initial latency
introduced by the route-discovery
procedure poses serious challenges for
reactive protocols.
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Related works
• Proactive Routing Protocols : In proactive
Routing Protocols (PRPs), the flip-side of
reactive protocols, maintain and update
information on routing between all nodes
of a given network at all times.
• Route updates are periodically performed
regardless of network load, bandwidth
constraints, and network size.
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Related works
• Hybrid routing protocols : Hybrid routing
protocols combine both the proactive and
reactive approaches.
• Zone routing protocol (ZRP) is a notable
example.
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Related works
• To avoid link rupture during data
transmission, a movement-prediction-based
routing (MOPR) is proposed in [13].
• MOPR predicts future positions of vehicles
and estimates the time needed for the
transmission of data to decide whether a
route is likely to be broken or not during
the transmission time.
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Related works
• The performance of the scheme largely
depends on the prediction accuracy and
the estimate of the transmission time that
depends, in turn, on several factors such
as network congestion status, driver’s
behavior, and the used transmission
protocols.
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Related works
• In [14], a distributed movement-based
routing algorithm is proposed for VANETs.
• This algorithm exploits the position and
direction of movement of vehicles.
• The metric used in this protocol is a linear
combination of the number of hops and a
target functional, which can independently
be calculated by each node.
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Proposed method
• The method to be proposed uses the RSSI
(Received Signal Strength Indication) of the
signal occurred in a vehicle and we predict
the link break down.
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Proposed method
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Proposed method
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Conclusion
• This proposal predicts the possibility yes or
no whether by using the RSSI value, it
finds out a distance and velocity
information and the pertinent node can
maintain a link or not.
• This prediction used first differential,
second differential of distance difference
for link maintenance.
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Conclusion
• By establishing the new link in case of
predicting with the breakage of a link it is
bitter and a throughput is increased and
the packet drop is ordered with reduction.
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