Chapter 11. Connecting to Event Hubs and an Introduction to IoT Hubs

This chapter provides a brief review of Azure Event Hubs and provides an introduction to IoT Hubs. It will teach you how to connect to Event Hubs and consume data using partitions and how to connect devices to the IoT Hub. It will discuss the various security and connectivity options available today when connecting devices to the Internet.

In this chapter, you will learn the following topics:

• What are Event Hubs and IoT Hubs

• When to use either Event Hubs or IoT Hubs

• How to send and consume messages

• How to enable bidirectional communication with IoT Hubs

• Using an Azure IoT Hub in a simulated real-world example

An introduction to Event Hubs

Event Hubs are primarily designed to ingest large volumes of event and telemetry data in a high throughput manner from a variety of devices and services. They are similar in principle to Azure Queues and Azure Topics but with different characteristics and use cases. Although Azure Queues and Topics are used for enterprise messaging scenarios in which transaction support, dead-lettering, ordered delivery, and guaranteed delivery are of prime concerns, Event Hubs are biased toward very high throughput and event processing scenarios such as stream analytics.

Security in Event Hubs

When a device sends data to an Event Hub, it is normally to a virtual endpoint address defined by the publisher. A publisher requires a valid token to be passed with each message, which is a combination of a shared access signature (SAS) and a publisher name. The publisher name is normally the device's unique identifier.

Although it is not recommended, you can directly connect to the Event...

Introduction to Azure IoT Hubs

Connected things have been around for decades in the manufacturing, utilities, and resources industries and have solved the very real requirement of needing to know and understand how large-scale systems are operating; they have provided the Operational Technology (OT) to the more commonly talked about Information Technology (IT).

An example of such a system is supervisory control and data acquisition (SCADA). Typically, a SCADA system consists of a large number of networked sensors reporting their data over proprietary protocols to a central resource that displays information and allow the decisions to be made. The data is stored in a large database known as a historian for ongoing analysis. These industrial control systems have existed for many years and are largely secure by default as they isolate the sensors and controls in a private network, for example, a process control network.

Because SCADA systems are largely proprietary or at least based on a few...

Scenario - bringing it all together

In this scenario, Sunny Electricals manufactures industrial electric motors. To ensure that these motors are well maintained, Sunny Electricals has embedded piezo sensors near the bearing housing and temperature sensors in the stator windings. These sensors are then wired to a microcontroller that sends the telemetry data to an Azure IoT Hub every minute.

With this information, Sunny Electricals can tell their customers of possible bearing failure or if the motor is working under stressful loads.

For the scenario, the microcontroller and telemetry data are simulated and posted to a single device in IoT Hub named motordata.

Once received by IoT Hub, the telemetry data is processed by an Azure Stream Analytics job that pushes all data to a Power BI dashboard to show the current data in an easily consumable format. The data is also processed using an Azure Function that makes use of the Event Hub endpoint of the IoT Hub. This process checks for error conditions...

Summary

In this chapter, we reviewed the functionality in Event Hubs to set the scene in order to take a deeper look at IoT Hubs.

The Internet of Things has been enabled due to the reduced cost of devices driven by a maker society and the advent of cloud computing.

This has driven a change in both cost and skills required to create a solution. By choosing cheaper hardware and standing up a simple pilot solution using Azure platform services, it is possible for organizations to understand the real value of a solution quickly, enabling them to move forward with confidence that the insights their IoT investment is delivering are valid and important.

Azure IoT Hubs are a key enabler to this process, providing a platform service that supports a near plug-and-play approach, while delivering trust in a secure solution that is difficult to compromise.

While physical devices can still be compromised, since they are outside the control of the Azure platform, having timebound and/or IP filtered secure...