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Specialized Network Formation: Long-Thin WSNs

National Chiao Tung UniversityDepartment of Computer Science

Yu-Chee Tseng

交通大學 /資訊工程系 /曾煜棋

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Introduction WSN deployment is a big concern in most practices. We propose a new long-thin (LT) topology for WSN

s. a hierarachical address assignment much better address pool utilization

Examples of LT WSNs: (bridges and roads)

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Limitations of ZigBee

In ZigBee, the length of a network address is 16 bit The maximum address capacity is 216=65536

Given Cm and Rm, the depth Lm will be very restrictive For example, given Cm=4 and Rm=2, the Lm ca

n only no more than 14 not suitable for LT WSNs !!

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Goals

(1) automatically form a LT network, (2) give addresses in a distributed manner, and (3) conduct routing

Assumption: consider only router-capable devices (ignore end devices)

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LT WSN: planning Carefully plan node placement before deploying a

WSN. Divide nodes into multiple clusters.

Each cluster is as a line segment

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LT network: Role Assignment

Nodes are divided into three types Cluster head node: the first node in a line segment Bridge node: the last node in a line segment Normal node

C

D

E

F

Coordinator

Network node

Cluster head nodeBridge node

B

A

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LT WSN: Logical Network After planning the network, the network manager can construct a

logical network GL

From GL, we can determine two parameters CCm: the maximum number of child of a node in GL

CLm: the depth of GL

C

D

E

F

Coordinator

Network node

Cluster head nodeBridge node

B

A

A

B

C

D

E

F

GL

CCm=2CLm=4

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LT WSN: Hierarchical Address Pool

Divided address into two parts: Cluster ID

assigned to nodes of GL: similar the orignial ZigBee scheme

Node IDassign to cluster members: according to their hop counts to the cluster he

ad

Challenge: how to perform this automatically a distributed node ranking scheme

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Contributions

The first work that promotes the long-thin topology for WSN

Propose a network formation protocol for LT WSN Propose a routing scheme suitable for LT WSN (omi

tted here)

Reference: M.-S. Pan, H.-W. Fang, Y.-C. Liu, and Y.-C. Tseng, "Ad

dress Assignment and Routing Schemes for ZigBee-Based Long-Thin Wireless Sensor Networks", IEEE VTC, 2008-Spring.