Client Server ====== ====== Get Handshake Initial -------------> Install tx 0-RTT keys 0-RTT - - - - - - - -> Handshake Received Get Handshake <------------- Initial Install rx 0-RTT keys Install Handshake keys Get Handshake <----------- Handshake Install tx 1-RTT keys <- - - - - - - - 1-RTT Handshake Received (Initial) Install Handshake keys Handshake Received (Handshake) Get Handshake Handshake -----------> Handshake Complete Install 1-RTT keys 1-RTT - - - - - - - -> Handshake Received Handshake Complete Handshake Confirmed Install rx 1-RTT keys <--------------- 1-RTT (HANDSHAKE_DONE) Handshake Confirmed