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. The RSA public key cryptosystem is based on the mathematical concept of modular exponentiation (numbers raised to one power by the module), as well as on certain mathematical constructs and the integer factorization problem (which is considered computationally impracticable for sufficiently large keys). An important issue is trust/proof that a particular public key is genuine, i.e. that it is correct and belongs to the claimed person or organization and that it has not been falsified or replaced by a malicious third party. There are several possible approaches, including: In the RSA system, the input message must be transformed into a large integer (for example. B with OAEP filling), while in ECC, the message cannot be encrypted directly and a more complex encryption scheme based on the Diffie-Hellman Key Exchange (ECDH) elliptic curve is used.

It will be explained in detail later in this chapter. In addition, asymmetric ciphers are significantly slower than symmetric ciphers (e.B. RSA encryption is 1000 times slower than AES). Key encapsulation (KEM) refers to the encryption of another key (symmetric or asymmetric). It is used to create overtly secure hybrid encryption schemes, para. B example to encrypt an AES secret with a specific ECC public key. Explanation The blacklist allows you to prevent users from installing and running certain apps on their mobile devices. Whitelisting allows an administrator to determine which applications and other software the user is allowed to install and run. Containerization is a technique used to separate different data sensitivities, such as corporate data and personal data, on a mobile device. Sandboxing separates apps from one another and doesn`t allow them to share execution, user, or data stores. The exponential exchange of keys in itself does not provide for any prior agreement or subsequent authentication between participants. It has therefore been described as an anonymous key memorandum of understanding.

Two of the most well-known applications of public key cryptography are: MIKEY can be used in three different modes: Preshared Key with Key Transport, Public Key with Key Transport, and Public Key with Authenticated DH Key Exchange. A subsequent extension provides for a DH exchange in pre-shared key mode. .