The present techniques generally describe a computer implemented method for establishing a secure communication session between a client device and a first server, the method performed by the client device comprising: obtaining, from a second server, credential data comprising a session identifier and cryptographic key data; performing a connection handshake with the first server to establish the secure communication session; creating a security state record defining one or more parameters used to establish the secure communication session, and associating the session identifier with the security state record; performing a first resumption handshake with the first server using the session identifier to re-establish the secure communication session.