TLS Cryptography In-Depth

18

TLS Cipher Suites

In the previous chapter, we revisited the TLS Record protocol from a higher-level perspective to understand how the individual cryptographic mechanisms – block ciphers, AEAD, and, in particular, the Galois counter mode – fit together to ensure confidentiality and integrity of data transmitted in TLS records.

In this chapter, we will cover TLS 1.3 cipher suites: combinations of ciphers and cryptographic algorithms that any TLS 1.3 endpoint must support and implement. In terms of RFC 8446 material, we will mainly cover the following:

• Subsection 9.1, Mandatory-to-Implement Cipher Suites

• Appendix B.4, Cipher Suites

In addition, we will introduce two additional cryptographic algorithms – ChaCha20 and Poly-1305 – that can be ...