State-of-the-art prozessorientierter Krankenhausinformationssysteme

A first cipher stream generated from a private key negotiated as a result of a public key exchange is partitioned to form a sequence of secondary keys. The secondary keys are then indexed. In one instance, each plaintext data packet is encrypted with a second cipher streams generated from a different one of the secondary keys. In another instance, a second cipher stream generated from a single secondary key is used to encrypt a plurality of plaintext data packets. A new second cipher stream generated from another one of the secondary keys is then used for encryption following each instance of the loss of a ciphertext data packet. The index is communicated with the ciphertext to identify which secondary key is to be used in generating the second cipher stream needed for decryption. With knowledge of the secondary key to be used, re-synchronization (along with new private key negotiation) at each instance of a ciphertext data packet loss is obviated.