18.1 Symmetric cipher suites in TLS 1.3
TLS 1.3 specifies a set of so-called symmetric cipher suites that Alice and Bob can use to protect the data transmitted via the TLS Record protocol. Each symmetric cipher suite is a pair composed of two cryptographic algorithms:
An AEAD algorithm used for protecting the confidentiality and integrity of TLS records
A hash algorithm used within the HKDF function to derive TLS secrets and shared keys
The name of a TLS symmetric cipher suite starts with the string TLS and has the following format:
TLS_<AEAD algorithm>_<Hash algorithm>where ¡AEAD algorithm and ¡Hash algorithm¿ are placeholders for specific algorithms. In addition, every cipher suite has a unique 2-byte identification value associated with it.
Table 18.1 shows the symmetric cipher suites that Alice and Bob can use according to the TLS 1.3 standard.
| Cipher suite | 2-byte identifier |
TLS˙AES˙128˙GCM˙SHA256 |
0x13,0x01 |
