beamstar: a new low-cost data routing protocol for wireless sensor networks shiwen mao and y. thomas...
TRANSCRIPT
BeamStar: A New Low-cost Data Routing Protocol
for Wireless Sensor Networks
Shiwen Mao and Y. Thomas HouThe Bradley Department of Electrical and Computer Engineering
Virginia Tech, Blacksburg, VA 24061Email: [email protected], [email protected]
Speaker : Ching - Chung Lin
Globecom 2004
Outline
Introduction Assumption BeamStar routing protocol Practical implementation Conclusion
Introducion
Characteristics are desirable for a routing protocol Scalability Low complexity Energy-efficiency Error-resilience
Introducion
Goals of the routing protocol minimum control overhead shift the control and management to base station
Components of the routing protocol Base station-assisted location discovery Location-aware data forwarding
AssumptionBase Station(s) :
Sensor node(s) :
Assumption
BeamStar requires the entire sensor network be within the maximum transmission range of the base station
BeamStar (Base station-assisted location discovery)
A node’s location is determined by 1. the directionality of the last base station transmission (Sector Number SN)
2. lowest power level information that it can receive from the base station (Ring Number RN)
We define the Location by {SN,RN}
BeamStar (Base station-assisted location discovery)
1
2
3
4 5 1
2
3
BeamStar (Base station-assisted location discovery)
( 1 , 1 )( 1 ,
2 )( 1 , 3 ) ( 2 ,
1 )( 2 , 2 )( 2 ,
3 )
( 3 , 1 )
( 3 , 2 )
( 3 , 3 )
( 4 , 1 )
( 4 , 2 )
( 4 , 3 )
BeamStar (Base station-assisted location discovery)
The packet format of a control message from the base station.
BeamStar (Location-Aware Data Forwarding)
The header fields are: BaseID : the identifier of the destination base station
SourceLocID: the location identifier, i.e., {RN, SN}, of the source sensor node. LastRelayLocID: the location identifier of the last sensor node that forwarded this data packet PacketSeqNumber: the sequence number of the packet
each node also maintains a sequence number table
{ 1 , 3}
{ 2 , 4}
{ 2 , 3}
{ 3 , 3}
{ 2 , 2}
BeamStar (Location-Aware Data Forwarding)
{ 3 , 2}
{ 1 , 2}
{ 3 , 1}
{ 1 , 1}
{ 2 , 1}
BeamStar (Location-Aware Data Forwarding)
There are many advantages of using this routing scheme. the intermediate sensor nodes do not need to store a routing table or maintain flow-state related information.
the storage requirement is also minimal.
the routes to the base station are loop-free
data packet is forwarded by multiple nodes through different routes
Practical implementation
A. Wake Up On-Demand B. Query for Events C. Creating Finer Regions D. Deploying Multiple Base Stations E. Reallocation and Reorganization
Practical implementation
A. Wake Up On-Demand To further conserve energy, we can put the sensor nodes to a “sleep” state after the initialization phase the dual radio design can be used to awake a sleeping sensor.
This wake up on-demand scheme is especially useful for sensor networks that monitor rare events
Practical implementation B. Query for Events
: sleep mode
Practical implementation
C. Creating Finer Regions
Practical implementation
D. Deploying Multiple Base StationsA B
(3,2){ 2 , 3 }
Practical implementation
D. Deploying Multiple Base StationsA B
(3,2){ 3 , 2 }
Practical implementation
E. Reallocation and Reorganization
Conclusions
BeamStar protocol Scalable energy efficient error-resilient routing
Thank you
Ad hoc sensors
BeamStar (Location-Aware Data Forwarding)
BeamStar (Location-Aware Data Forwarding)
Practical implementation
D. Deploying Multiple Base StationsA AB B
(2,3) (3,2)