The Internet of Things (IoT) is a paradigm that has brought about a new era of connectedness and collaboration and is revolutionizing the way we live and work. However, it comes with several new security challenges.

IoT devices, often connected to sensitive data and systems, attract attackers. The number and variety of devices connected to the internet and the quantity of data generated continue to increase. This data is often sensitive, confidential, or both.

One way to protect this data is through the use of cryptographic algorithms, the mathematical equations used to encode and decode data. This article explains how electronic devices use complex cryptographic algorithms to protect our information from attacks in IoT environments and how hardware accelerators with cryptographic functions enable this protection.

The ABCs of Cryptographic Functions

Cryptographic algorithms encrypt and decrypt data using mathematical functions. Designed to be very difficult to break, these algorithms are essential for keeping information safe.

Specialized microchips or security coprocessors, known as cryptographic hardware accelerators, perform cryptographic algorithms very quickly. These kinds of devices can achieve complex cryptographic functions faster than software-based algorithms.

3 Types of Cryptography in IoT

There are three main types of cryptographic algorithms: message authentication, message integrity, and security functions.

#1: Message Authentication

A Message Authentication Code (MAC) detects message tampering by generating a cryptographic checksum on the data. The MAC algorithm uses a secret key to create a message digest, which the algorithm then appends to the message.

The sender sends the message and digest to the receiver, who then uses the same secret key to generate a message digest from the received message. If both digests match, the receiver knows there’s been no tampering.

#2: Message Integrity

Message integrity is the ability of a message to resist modification or corruption while in transit. Integrity is crucial because it ensures the message received matches the message sent. To achieve message integrity, cryptographic hash functions are used.

A cryptographic hash function takes an arbitrary block of data and produces a fixed-size hash value. The hash value is a summary of the original data, and it is nearly impossible to produce the same hash value from two different pieces of data.

#3: Security Functions

Cryptography handles various IoT security functions, including digital signatures, key exchange, and encryption. A digital signature is a mathematical scheme for demonstrating the authenticity of a digital message or document.

Encryption is the process of transforming readable data into an unreadable format that protects it from being read if intercepted.

Main Threats for IoT Devices Today

The number of IoT devices connected to the internet makes them desirable prey for malicious hackers. There are a few types of attacks that these devices often encounter the following:

• Random data or fuzzing attacks: Fuzzing attacks involve feeding random data to an application or system to crash it or force it to reveal information. This type of attack can be difficult to detect and can be used to exploit vulnerabilities in a system.
• Rowhammer attacks: Rowhammer attacks exploit a hardware vulnerability in some types of DRAM (dynamic random-access memory) chips. This type of attack can be used to gain access to sensitive data or to cause denial-of-service conditions.
• Side-channel attacks: Side-channel attacks exploit the side effects of cryptographic algorithms, leaking information about the algorithm or the data being processed. Attackers use this type of attack to compromise the security of cryptographic systems.
• Trial and error attacks: Trial and error attacks involve trying different values for a secret key until the correct one is found. Attackers use this method to compromise the security of cryptographic systems.

Mutual Authentication: A Practical Example

As we mentioned, cryptography can play a vital role in securing IoT. It can be used to protect data in transit to authenticate devices and users and to provide access control.

In this section, we will focus on how cryptography can be used for mutual authentication, which is a crucial security measure for IoT devices.

Mutual authentication is a process in which both parties in a communication verify each other’s identity. Unlike single-factor authentication, which authenticates only one party (usually the user), mutual authentication ensures that both parties are legitimate. This is crucial for IoT devices, as it ensures that data exchanges occur only between authorized devices.

Furthermore, mutual authentication can help to prevent man-in-the-middle attacks, in which an attacker intercepts communication between two parties and impersonates one of them.

Azure RTOS (Now Eclipse ThreadX) is a secure operating system that provides a foundation for building reliable and secure applications. The RTOS includes several security features, including support for PKCS#11, which is a standard interface that allows an operating system to communicate with a hardware security module (HSM).

The Azure RTOS supports several HSMs, including modules that store sensitive data like cryptographic keys. Some of these modules include a built-in true random number generator (TRNG) that generates the shared secret.

Secure Boot is a security feature that is built into Azure RTOS. It ensures that only signed, approved software can run on the system. This helps to protect the system from malicious code and other security threats.

More Resources for Boosting IoT Security

You can build your IoT networks with various products like sensors, development platforms, and connectivity devices, but security in IoT cannot be overlooked.

Solutions need to cover both software and hardware attacks and include features for:

• Secure Boot
• Secure OTA firmware update
• Secure Key storage
• Authentication
• Encryption
• Serial bus encryption
• Hardware attacks and tamper protection
• Detecting and managing abnormal situations
• IP protection for software

And the above are only a few of the possibilities. Today, it is possible (and necessary) to find devices and solutions that help protect IoT products from the initial design and manufacturing stages to the very end of the product’s lifecycle to comply with major IoT certification requirements and ensure the highest level of security.

Main Takeaway

Data is becoming more valuable than ever, and this trend is likely to continue and evolve in the future. As IoT devices become more pervasive in our lives, so does the importance of having strong cybersecurity mechanisms to protect them against malicious attacks.

This article explored the main cryptography techniques to protect IoT devices from attacks, the more frequent kinds of attacks that these devices experience, and the main products that are ideal for achieving state-of-the-art protection in today’s scenario. For more in-depth technical information about these IoT security devices and solutions, visit the security hub on the Mouser Electronics website.