TLS 1.3 vs TLS 1.2 Handshake Comparison

1-RTT vs 2-RTT

Side-by-side protocol latency, early ECDHE KeyShare, and encrypted handshake records

Step 1 of 12
Speed
LEGACY LANE: TLS 1.2 Handshake (2-RTT Overhead)
MODERN LANE: TLS 1.3 Handshake (1-RTT + Encrypted Certs)
Client (TLS 1.2)
2-RTT Negotiator
IDLE
Cipher: ECDHE_RSA_AES128
Nonce: awaiting
Pre-Master: none
Master Sec: none
RTT Elapsed 0.0 RTT
Server (TLS 1.2)
Plaintext Cert Sender
IDLE
Cert Exposure: Plaintext X.509
Key Exchange: Waits for Flight 3
App Key: uninitialized
Handshake Ready: 2.0 RTT
Client (TLS 1.3)
1-RTT Early KeyShare
IDLE
Cipher: TLS_AES_128_GCM
KeyShare: none
Shared Sec: none
Traffic Key: none
RTT Elapsed 0.0 RTT
Server (TLS 1.3)
Encrypted Handshake
IDLE
Cert Exposure: {Encrypted AEAD}
KeyShare: x25519 Ephemeral
Traffic Key: uninitialized
Handshake Ready: 1.0 RTT (Saves 1 RTT!)