The two key exchange algorithms that consume the most resources when decrypting SSL traffic are ECDHE and DHE. These are both Diffie-Hellman based algorithms that enable perfect forward secrecy (PFS), which means that they generate a new and unique session key for each SSL/TLS session, and do not reuse any previous keys. This enhances the security of the encrypted communication, but also increases the computational cost and complexity of the key exchange process. ECDHE stands for Elliptic Curve Diffie-Hellman Ephemeral, which uses elliptic curve cryptography (ECC) to generate the session key. DHE stands for Diffie-Hellman Ephemeral, which uses modular arithmetic to generate the session key. Both ECDHE and DHE require more CPU and memory resources than RSA, which is a non-PFS algorithm that uses public and private keys to encrypt and decrypt the session key123. References: Key Exchange Algorithms, Best Practices for Enabling SSL Decryption, PCNSE Study Guide (page 60)