Book Image

Learning Internet of Things

By : Peter Waher
Book Image

Learning Internet of Things

By: Peter Waher

Overview of this book

<p>This book starts by exploring the popular HTTP, UPnP, CoAP, MQTT, and XMPP protocols. You will learn how protocols and patterns can put limitations on network topology and how they affect the direction of communication and the use of firewalls. Thing registries and delegation of trust are introduced as important tools to secure the life cycle of Things on the Internet. Once the fundamentals have been mastered, your focus will move to the Internet of Things architecture. A secure architecture is proposed that will take full advantage of the power of Internet of Things and at the same time protect end user integrity and private personal data without losing flexibility and interoperability.</p> <p>This book provides you with a practical overview of the existing protocols, communication patterns, architectures, and security issues important to Internet of Things.</p>

Related Content you might be interested in

Current Title:

Small book image
Learning Internet of Things
Peter Waher
Jan, 2015 | 242 pages
No titles found
Table of Contents (16 chapters)
Learning Internet of Things
Learning Internet of Things
Credits
Credits
About the Author
About the Author
About the Reviewers
About the Reviewers
www.PacktPub.com
www.PacktPub.com
Preface
Preface
Free Chapter
1
Preparing our IoT Projects
Preparing our IoT Projects
Creating the sensor project
Creating the actuator project
Creating a controller
Creating a camera
Summary
2
The HTTP Protocol
The HTTP Protocol
HTTP basics
Adding HTTP support to the sensor
Adding HTTP support to the actuator
Adding HTTP support to the controller
Summary
3
The UPnP Protocol
The UPnP Protocol
Introducing UPnP
Creating a device description document
Creating the service description document
Providing a web interface
Creating a UPnP interface
Implementing the Still Image service
Using our camera
Summary
4
The CoAP Protocol
The CoAP Protocol
Making HTTP binary
Adding CoAP to our sensor
Adding CoAP to our actuator
Using CoAP in our controller
Summary
5
The MQTT Protocol
The MQTT Protocol
Publishing and subscribing
Adding MQTT support to the sensor
Adding MQTT support to the actuator
Adding MQTT support to the controller
Summary
6
The XMPP Protocol
The XMPP Protocol
XMPP basics
Adding XMPP support to a thing
Providing an additional layer of security
Adding XMPP support to the actuator
Adding XMPP support to the camera
Adding XMPP support to the controller
Connecting it all together
Summary
7
Using an IoT Service Platform
Using an IoT Service Platform
Selecting an IoT platform
The Clayster platform
Interfacing our devices using XMPP
Creating our control application
Summary
8
Creating Protocol Gateways
Creating Protocol Gateways
Understanding protocol bridging
Using an abstraction model
The basics of the Clayster abstraction model
Understanding the CoAP gateway architecture
Summary
9
Security and Interoperability
Security and Interoperability
Understanding the risks
Modes of attack
Tools for achieving security
The need for interoperability
Summary
Index
Index

Adding MQTT support to the actuator

The actuator will act as a subscriber in the MQTT network by subscribing to the commands published on specific command topics. Before we enter the main loop, we create an MQTT client connection in the same way we did for the sensor:

MqttClient MqttClient = new MqttClient("iot.eclipse.org", MqttClient.DefaultPort,"LearningIoTActuator", string.Empty, false);
MqttClient.Open();
MqttClient.CONNECT(20, true);

Initializing the topic content

We can take advantage of this opportunity to also publish the current (or saved) states of the actuator output to the topics we will soon subscribe to. This is to make sure that the output and topic contents are consistent. Let's have a look at the following code:

MqttClient.PUBLISH("Clayster/LearningIoT/Actuator/ao", 
  state.Alarm ? "1" : "0", MqttQoS.QoS1_Acknowledged, true);
MqttClient.PUBLISH("Clayster/LearningIoT/Actuator/do", 
  wsApi.GetDigitalOutputs().ToString(), 
  MqttQoS.QoS1_Acknowledged, true);

for (i = 1; i ...
Previous Section
End of Section 4
Next Section