This chapter is directed squarely at IoT implementers, those developing IoT devices (consumer or industrial) or integrating IoT communications into their enterprises. It provides you with an A to Z for their IoT implementations and deployments. While most of this book is devoted to practical application and guidance, this section diverges a bit to delve into deeper background topics associated with applied cryptography and cryptographic implementations. Many security practitioners will find this information common sense, but given the myriad cryptographic implementation errors and deployment insecurities even security-aware tech companies continue to deploy, we decided this background was needed. The risks are growing worse, evidenced by the fact that many industries historically unfamiliar with security (for example, home appliance vendors) continue to network-connect and IoT-enable their products. In the process, they make many avoidable errors that can harm their customers.

A detailed review of the use of cryptography to protect IoT communication and messaging protocols is provided, along with guidance on how the use of certain protocols drives the need for additional cryptographic protections at different layers of the technology stack.

This chapter is a critical prerequisite to the chapter on Public Key Infrastructures (PKIs) and their use in IoT identity and trust management. It explains the underlying security facets and cryptographic primitives on which PKIs depend.

This chapter is broken up into the following topical sections:

• Cryptography and its role in securing the IoT
• Types and uses of cryptographic primitives in the IoT
• Cryptographic module principles
• Cryptographic key management fundamentals
• Future-proofing your organization's rollout of cryptography