This article offers the next level of detail for protecting the Internet of Things (IoT) infrastructure that is built on the Azure IoT hub. It provides links to information on how to deploy and configure each component at the implementation level. It also provides comparisons and alternatives between other competing strategies.
Securing the Azure IoT hub deployment can be divided into the following three security areas:
- Device security is protecting an Internet of Things device while in use.
- Connection Security: Ensuring the confidentiality and integrity of all data exchanged between the IoT device and IoT Hub.
- The ability to safeguard data while it is being stored and sent across the cloud.
Secure device provisioning and authentication
By linking the symmetric key to each call, the security token technique enables authentication for each call the device makes to the Azure IoT Hub. As part of the TLS connection formation, X.509-based authentication enables authentication of an IoT device at the physical layer. It is possible to utilize the security-token-based approach without the X.509 authentication, albeit this is a less secure structure. The decision between the two approaches is determined mainly by the level of security required for device authentication and secure storage on the device (to store the private key securely).
IoT Hub security tokens
To avoid transferring keys over the network, IoT Hub uses security tokens to identify devices and services. Security tokens have additional restrictions on their scope and time of validity. Tokens are automatically generated by Azure IoT SDKs without the need for any additional configuration. However, in some circumstances, the user must directly create and utilize security tokens. The implementation of the token service pattern or direct usage of the MQTT, AMQP, or HTTP surfaces is some examples of these scenarios.
The following articles provide more information on the security token’s composition and application:
- SAS tokens being used as a device
- Security token architecture
Each Azure IoT Hub has an identity registry that may be used to generate per-device resources in the service, such as a queue that holds in-flight communications from the cloud to the device and grants access to the device-facing endpoints. Secure storing of device IDs and security keys is made possible by the IoT Hub identity registry. It is possible to completely regulate device access by adding specific device identities or groups of identities to an allowlist or a blocklist. The following articles can find more information on the identity registry’s design and the operations it supports.
Access control settings and per-device security credentials can be configured using the Azure IoT Hub identity registry. However, an IoT solution can be linked to an existing infrastructure using IoT Hub by developing a token service if it has already made a sizable investment in a unique device identity registry and/or authentication mechanism.
Root certificate on the device
The IoT device uses a root certificate that is included in the device SDK to authenticate IoT Hub while establishing a secure TLS connection with it. Even though these root certificates have a long lifespan, they could nevertheless become invalid or expire. The device might not be able to connect to the Azure IoT Hub in the future if there is no means to update the certificate on it (or any other cloud service). This risk is effectively reduced by having a way to update the root certificate after the IoT device is put into use.
Securing the connection
If you opt for the utilization of the Transport Layer Security (TLS) protocol, the internet connection between the Internet of Things device and IoT Hub is protected. TLS 1.2, TLS 1.1, and TLS 1.0 are all supported by Azure IoT in that sequence. TLS 1.0 support is solely offered for backward compatibility.
Securing the cloud
For each security key, Azure IoT Hub enables the development of access control policies. Each of the endpoints on IoT Hub is accessible via the following set of permissions. Access to an IoT Hub is restricted by permissions based on functionality.
- RegistryRead gives the identity registry read access. See the identity register for more details.
- ServiceConnec gives users access to communication and monitoring endpoints for cloud services. It permits, for instance, back-end cloud services to send and receive device-to-cloud messages as well as to send texts or messages from one device to another and collect the accompanying delivery acknowledgments.
- DeviceConnect access to endpoints facing devices is granted. It permits, for instance, the transmission of device-to-cloud and device-to-cloud messages.
Why is MQTT important for IoT?
MQTT has got its recognition as the leading protocol for IoT solutions in recent years. There are various reasons for this. Firstly, one of the IoT protocols that are now used is the lightest. Since it is an open standard, any hardware or software can use it. The availability of client libraries for all popular programming languages makes it simple to create IoT applications utilizing MQTT.
In order to develop and deploy an IoT infrastructure using Azure IoT, this article provides an overview of implementation level details. Securing the IoT infrastructure as a whole depends on configuring each component to be secure. The design options offered by Azure IoT hub provide some flexibility and choice, but each option may have security repercussions. It is advised that a risk/cost analysis be used to assess each of these options.
The main goal of Akenza is to give many users simple access to the Azure IoT hub. Solutions that support an agile approach to development and innovation are required in today’s highly volatile technology landscape. We are confident that we can guide the Internet of Things into a widespread market application by significantly decreasing the time and complexity that businesses must expend when developing IoT solutions. There are countless scenarios in which we could connect our environment. It comes down to awareness, expense, and complexity.