Trusted communication between a first computing device and a second computing device in a transaction process is established as follows. A communication channel is established between the first computing device and the second computing device. The first computing device provides a secure communication to the second computing device, this secure communication comprising cryptographic material encrypted by a first cryptographic method. The second computing device decrypts the secure communication using a key already available to it. The first and the second computing device then communicate where trusted communication is required by a second cryptographic method using the cryptographic material. A suitable first computing device and second computing device are also described.