Designing Secure IoT Devices with the Arm Platform Security Architecture and Cortex-M33

Chapter 5: Cryptography—Secure communications

Abstract

As we saw in the last chapter, a modern block cipher will allow two stations to communicate in private across an insecure channel. If both stations are able to agree on a secret key in advance through a secure channel, then establishing an encrypted channel can be straight forward although as we will see later, it is not without its problems. However, in many systems, the use of a “preshared key” is impractical. This means that a session key must be agreed between both stations over the insecure channel. This is a nontrivial problem that is addressed by the Transport Layer Security (TLS) protocol.

Keywords

Cryptography; Ciphers; Malleability; Security; Encrypt; Decrypt

Introduction

As we saw in ...