16/19/2015 EFFICIENT PARKING METER MANAGEMENT SYSTEM APRIL 26, 2006 STEPHEN DABIDEEN YIZENIA MORA ADVISORS: DR. ROCH GUERIN AND DR. SALEEM KASSAM

26/19/2015 Project Overview  Assumptions  City-wide wireless network  Parking meters with wireless and sensing capabilities  Goal  Get information about the meters’ status to a central office  Objectives  Design and implement communication protocol  Evaluation metrics: reliability and energy efficiency

36/19/2015 Central Station

46/19/2015 Statement of Problem

56/19/2015 Hardware

6 Hardware

7 Head Meter Rotation  Goal: maximize the life of the system  Transmitter with two levels of power  Evenly distribute role of head meter Option 1: fixed, predefined rotationOption 1: fixed, predefined rotation Option 2: dynamically determined rotationOption 2: dynamically determined rotation  Pick the neighbor with highest battery level

86/19/2015 SAFE  Goal  Reliably and Efficiently route information to the current head meter  Routing table  Local  Next hop  A function of distance and reliability  Link Quality  Additive Increase Multiplicative decrease  Synchronization  Store & Forward - single transmission per cycle

96/19/2015 Single-Path, Best-Effort Routing  Data sent to best next hop and forwarded if received

106/19/2015 Single-Path, Best-Effort Routing  Packets lost due to collisions  Data loss cumulative Data Missed

116/19/2015  Cost to send a packet of size b (b = 8):  Energy = 1.9 * b μJ Incremental cost fixed cost Incremental cost fixed cost  Cost to send x times:  Energy = [1.9*b + 266]*x μJ  Cost to send through x Paths Since data piggy-backs on other packets:Since data piggy-backs on other packets:  Energy = [1.9*b]*x μJ Multi-Transmission vs. Multi-Path

126/19/2015 Full Multi-Path Routing  Improves reliability  More paths = More energy Data Missed

136/19/2015 SAFE  Synchronized Adaptive-Forwarding Efficient Routing Protocol  Defines two types of paths  Primary: Deterministic Best-Effort  Secondary: Probabilistic  Central station provides feedback  Adaptive-Forwarding: Probability Matrix used to create secondary paths as needed  Synchronization

146/19/2015 Probabilistic Multi-Path Routing  Reduces redundancy without sacrificing reliability  Uses multi-path only when needed Primary Path Secondary Path

156/19/2015 Probabilistic Multi-Path Routing Primary Path Secondary Path  Fewer Paths, Same level of reliability

166/19/2015 The SAFE Probability Matrix  3-D matrix Meter, Current Head Meter, ProbabilityMeter, Current Head Meter, Probability  Determination Proactive ResponseProactive Response  Long term, time-of-day variations Reactive ResponseReactive Response  Temporary, unpredicted periods of unreliability  User chooses tradeoff Reliability vs. energy consumptionReliability vs. energy consumption

176/19/2015 Failure Recovery  Loss of a head meter Transient loop => count to infinityTransient loop => count to infinity  Loss of a non-head meter Link Quality decreasesLink Quality decreases  Fragmentation Head meter in each groupHead meter in each group  Defragmentation Single head meterSingle head meter

186/19/2015 Experimental Results  Energy calculations for transmitting and receiving only  Group of 6 meters Routing Type Reliability (% data loss) Energy Consumption (J/cycle) Best-Effort, Single Path SAFE: 10% response SAFE: 30% response Full Multi-Path

196/19/2015 Conclusion  Goal and Objectives  SAFE routing protocol  Two types of paths: primary and secondary  Probabilities determined by the central station  Allows the user to trade reliability for energy efficiency  Designed for our project but easily adaptable

206/19/2015 Acknowledgements  Prof. Roch Guerin (Advisor)  Prof. Saleem Kassam (Advisor)  Prof. CJ Taylor (Instructor)  Prof. Ken Laker (Instructor)  Mr. Phil Farnum (Instructor)  Mr. Sid Deliwala (Gismos & Gadgets)  TCOM Lab (StarEast Boards)  CIS & ESE Departments (Funding)