December 15, 2022

The 2023 Guide to Public Key Infrastructure (PKI) in IoT Security

smart city and wireless communication network

In this article, we will explore the basics of PKI as it applies to IoT security and offer up our 2023 guide on setting up this technology for your own devices.

We’ll discuss the importance of PKI in strengthening authentication and encryption protocols, as well as how it can be used to ensure data integrity. We’ll also look at the different types of PKI systems available on the today and which ones you should be using in your organisation. Read on to learn more!

What is PKI: Keys and Digital Certificates

Public key infrastructure (PKI) is a set of roles, policies, and processes that are used to; create, manage, distribute, use, store, and revoke digital certificates and public keys. PKI is essential for establishing secure communications in IoT systems.

Digital certificates are used to authenticate devices and users, and to encrypt data. They provide a way to verify that a device or user is who they claim to be, and they protect data from being eavesdropped or tampered with.

Public keys are used to encrypt data or to digitally sign data. They can be used to verify that a message has not been tampered with, and they can be used to encrypt data so that only the holder of the corresponding private key can decrypt it. Private keys are used to decrypt data or to digitally sign data.

PKI can be used in conjunction with other security measures, such as firewalls and intrusion detection systems, to create a comprehensive security system for IoT devices and networks.

Importance of PKI certificates in IoT Security

IoT devices are becoming increasingly popular as they offer a convenient way to connect to the internet and perform various tasks. However, these devices are also susceptible to security threats, which is why it’s important to understand how public key infrastructure (PKI) can be used to secure them.

PKI is a system of digital certificates and keys that can be used to authenticate and encrypted communications between devices, assigned by certificate authorities. By using PKI, IoT devices can be assured that they are communicating with the intended recipient and that their data remains confidential.

There are a few things to keep in mind when using PKI for IoT security:

  1. Make sure you’re using a reputable PKI provider.

There are many providers out there, but not all of them are created equal. Do your research to find a provider that offers robust security features and has a good reputation.

  1. Pay attention to certificate expiration dates.

All digital certificates have an expiration date, and it’s important to keep track of this so you can renew them before they expire. If a certificate expires, it can no longer be used to secure communications.

  1. Keep your private keys safe.

Private keys are what allow you to access your digital certificates, so it’s important to keep them safe from unauthorised access. Store them in a secure location and make sure they’re backed up in case they’re lost or stolen.

The Importance of PKI

As we’ve established, public key infrastructure (PKI) is a system of digital credentials and certificates that is used to authenticate devices and communication between them. It is a critical component of IoT security, as it helps to ensure that only authorized devices can access data and resources.

Moreover, encrypted communication protocols help to prevent unauthorised parties from reading sensitive data that is transmitted, so that even if data is intercepted, it would be difficult for an unauthorised party to read it adding transport layer security. PKI is becoming increasingly important as the internet of things continues to grow and expand.

PKI also helps to ensure that only authorised devices can access data, preventing malicious actors from gaining access and manipulating systems. Each device, being registered with its own private key and public key, enables more seamless digital identities for devices, which helps secure the large networks of devices across the IoT.

How PKI works: Digital Certificates

First, a registration authority will assign digital certificates from a certificate database. These are trusted third party providers who manage public key encryption. Once you have received your private and public keys, they will act as digital signatures for their assigned devices.

Public Keys and Private Keys

In PKI, each device has a unique digital certificate that contains a public key and a private key. The private key is used to sign messages and the public key is used to verify signatures. PKI can be used to authenticate devices, encrypt communications, and ensure the integrity of data.

To ensure security, you will keep your own private key as a secret key used to authenticate users of the device. Keeping this key secret is critical to PKI security, as this is how you will ensure secure communication of the encrypted message.

The Benefits of PKI in IoT security

The proliferation of the Internet of Things (IoT) has led to increased security concerns, as the number of devices and sensors connected to the internet grows. PKI can help to secure IoT devices and data, by providing a way to authenticate devices and exchange encrypted data.

PKI can be used to authenticate devices, so that only authorized devices can access data or services. This is important in preventing unauthorised access to sensitive data or tampering with device settings. PKI can also be used to encrypt data, so that it can only be read by authorized devices. This helps to protect data from being intercepted or tampered with during transmission.

Overall, the benefit of PKI is that it provides a robust way to secure IoT devices and data. Through public key cryptography and digital encryption, PKI can help to ensure that only authorized users have access to sensitive information, and that data is not compromised during transmission.

The Challenges of PKI in IoT security

PKI, or Public Key Infrastructure, is a system that uses public and private keys to encrypt and decrypt data. It is often used in conjunction with other security measures, such as firewalls and intrusion detection systems. PKI can be used to secure communications between devices, as well as to authenticate devices and users.

However, PKI has its own set of challenges when it comes to IoT security. First, the number of devices that need to be authenticated and secured can be overwhelming. In addition, many IoT devices are not powerful enough to run PKI on their own – they need to rely on infrastructure provided by manufacturers or service providers.

This can create a single point of failure – if the manufacturer’s or service provider’s systems are compromised, then all of the devices that rely on them are at risk. In addition, updates and changes to PKI systems can be difficult to deploy in a timely manner across all affected devices.

PKI can be an important part of an IoT security strategy, but it is important to be aware of its limitations. Working with a trusted partner who specialises in PKI and IoT security can help ensure that your system is properly configured and implemented.

Implementing PKI in IoT security

Implementing PKI in IoT security can help to improve the overall security of an IoT system. It can make it more difficult for hackers to access data, and it can also help to ensure that only authenticated devices are able to communicate with each other.

To ensure PKI is implemented correctly, a certificate management system is a great option, as the number of keys and their dates for renewal can be a complicated task to manage manually, especially if there are large numbers of connected devices. Using a certificate management system to issue digital certificates and revoke digital certificates creates an easier to manage network.

The Future of PKI

As our world becomes more and more digital, the importance of PKI in IoT security will only continue to grow.

Here are some potential future applications of PKI in IoT security:

1. Increasing use of elliptic curve cryptography (ECC) for smaller, more efficient keys that are better suited for constrained devices.
2. Implementation of quantum-resistant algorithms to protect against emerging quantum computing threats.
3. Use of blockchain technology to create tamper-proof records of PKI data and transactions.
4. Development of new standards and protocols for improved interoperability between different PKI systems.
5. Introduction of new technologies such as biometrics and trusted platform modules (TPMs) for additional security layers.


The 2023 Guide to Public Key Infrastructure (PKI) in IoT Security has provided an overview of the evolving landscape of PKI and its emerging role as a cornerstone technology for securing Internet of Things devices.

We have explored the different approaches and technologies used to implement PKI, along with detailing practical considerations such as scalability, interoperability and user experience when selecting.

Additionally, we have also discussed how organizations can leverage modern tools like automation and artificial intelligence in their PKI deployments. All these insights should equip you with everything you need to make informed decisions about your organisational security posture in today’s highly connected world.


Louise José