Alice uses her private key and Bob`s public key to create a secret key. In the KeyAgreement class, this requires two phases: one that uses its private key and one that uses its public key. Due to its computing inefficiency compared to symmetric key, public-key cryptography is generally not used for encryption and decryption, especially not for mass data processing, e.B. in a VPN session or full disk encryption device. However, public-key cryptography is preferred for both digital signatures (origin authentication) and the secure distribution of ephemeral symmetric keys. To repeat, in public-key cryptography, as shown in Figure 4.20, the sender and recipient of a message have two different but paired keys: the encryption key that is published; and the decryption key known only to the recipient. We call the encryption key a public key (PK); and its paired key, the recipient`s private key (PRK). The pre-installed enclosure is by far the most efficient way to handle key transport, as only symmetric cryptography is used. This approach also has the advantage that only a small amount of data needs to be exchanged.

The problem, of course, is scalability, as it`s not always possible to share individual keys with a large group of peers. Therefore, this case mainly deals with scenarios such as server-to-client and also cases where public key modes have already been used and thus allow the “cache” of a symmetric key. Let G be a large cyclic multiplicative group with generator for a fixed cyclic group. This method creates a DH key that is used as a TGK. This method is used only for creating individual peer-to-peer keys, not for groups. Pseudonymous communication can be achieved using traditional public-key cryptography chemistries by equipping vehicles with a set of public key certificates and corresponding key pairs (Bissmeyer et al. 2011). Public key certificates are exempt from any identifying information and are used as non-cancellable pseudonyms.

The vehicles sign the messages with the secret key of the currently active pseudonym and attach the resulting signature and the pseudonym certificate corresponding to the message. Recipients can verify a message signature against the pseudonymous certificate, but cannot determine the sender`s vehicle ID….