Technical requirements
As hardware, we only need an ESP32 devkit and a DHT11 sensor.
You can find the code for the chapter examples at this link: https://github.com/PacktPublishing/Internet-of-Things-with-ESP32/tree/main/ch10.
The common libraries are located here: https://github.com/PacktPublishing/Internet-of-Things-with-ESP32/tree/main/common.
We need a new external library while developing the AWS example, which can be cloned from this repository: https://github.com/espressif/esp-aws-iot.git.
An AWS account and an Identity and Access Management (IAM) user are required. This documentation explains how to do that if you don't have an AWS account: https://docs.aws.amazon.com/polly/latest/dg/setting-up.html.
Eclipse Mosquitto is the MQTT message broker that we will use in this chapter. It also provides the client applications to connect to any message broker. This page helps with the installation: https://mosquitto.org/download/.
In the CoAP server example, we...