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LIST OF FIGURES
FIGURE NO. TITLE PAGE NO.
1.1 LED 3
1.2 Buzzer 3
1.3 LM35- Analog temperature sensor 4
1.4 DHT11- Digital temperature sensor 4
1.5 Light Dependent Resistor (LDR) 5
1.6 IR LED and IR photodiode 5
1.7 Organization of thesis 16
2.1 Comparison chart of proposed vs. existing testbeds 24
3.1 A typical information processing system 26
3.2 Basic IoT architecture 29
3.3 Proposed testbed architecture 30
3.4a Functional architecture of the proposed open
IoT architectural framework 31
3.4b Detailed architecture of the proposed open
IoT architectural framework 32
3.5 Consolidated service set 36
3.6a Boards discovered as resources 37
3.6b Screenshot of sensor resource discovery 37
3.7 Screenshot of database updates 37
3.8a Sensor/actuator clients detection time 38

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3.8b Sensor/actuator detection time 38
3.8c Disconnected sensor/actuator time 39
3.9 User request hit ratio 39
4.1 Sample record database displayed in the Web UI 47
4.2 Visualization of DHT11’s temperature data 48
4.3 Visualization of DHT11’s humidity data 48
4.4 Experimental prototype for sensor client 51
4.5 Communication model for sensor client 52
4.6 Conversation flow between the protocol broker, message
broker and the database 54
4.7 Structure of the table for sensors with single
parameter 58
4.8a Structure of the table for sensors (DHT11) with
multiple parameters 58
4.8b Structure of the table for sensors (color) with
multiple parameter 58
4.9 Experimental setup of the proposed system
(sensors interfaced with sensor client and connected 59
to the Router)
4.10 Event collaboration model vs. traditional request
response model 60
4.11 Comparison on updation time: Approach 4 outperforms 61
4.12 Gas sensor table updation time 62
4.13 Sensor database entries 63

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4.14 Snapshot of the database showing the table content
for DHT11 sensor 65
5.1 Actuator Client-an experimental prototype 72
5.2 Request response of actuator client 73
5.3 Resource access through the resource requisition algorithm 75
5.4 Acquiring lock through getLock API 78
5.5 Release lock through releaseLock API 79
5.6 Platform as a service- an experimental prototype 81
5.7 A module of experimental set up for platform as service 82
5.8 Slot based interaction between user and the web UI 83
5.9 WebUI interface 83
5.10 Illustration of a sample API function call 85
5.11 Snapshot demonstrating API package download 86
5.12 Snapshot to demonstrate the use of sample API functions 86
5.13 API for sensors and actuators 87
5.14a-5.14b API Execution time for sensors and actuators
accessed locally 88
5.14c-5.14d API Execution time for sensors and actuators
accessed from remote 89
5.15 Snapshot of API call and response 90
5.16 Compilation and upload time comparison between
Arduino IDE and the proposed testbed service 91
6.1 Allocation decision tree 95
6.2a State machine for testbed service 96

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6.2b State transition graph for testbed service 96
6.3 Service usage pattern and the utilization
(successful access) rate 103
6.4 User usage rate of the proposed testbed 104
6.5a Novice user usage pattern 104
6.5b Academic user usage pattern 105
6.5c Industrial user usage pattern 105
6.5d Data analyst usage pattern 106
6.5e Researcher usage pattern 107