Goals of Key Agreement Sample Clauses

Goals of Key Agreement. ‌ The fundamental goal of any key agreement protocol is to securely establish a common secret key by distributing keying data between two entities. Both entities should influence the outcome of the key, thus preventing an undesired third-party from injecting any weak keys on the agreeing parties. A key agreement protocol should be able to withstand both active attacks (in which an adversary injects, deletes, alters, or replays a message) and passive attacks (in which an adversary simply observes the protocol exchange and prevents it from acheiving its goals). In [12], Xxxx proposed a classification of design goals divided into intentional and extensional goals. Intentional goals are generally concerned with ensuring that the pro- tocols run correctly as specified, while extensional goals are concerned about what a protocol is designed to achieve for its participants. In key agreement, the following ex- tensional goals are desired. • Implicit Key Authentication. A key agreement protocol provides implicit key au- thentication if an entity can be assured that none other than the intended entities can obtain the value of the secret key. A protocol in which this assurance is given to all participants is called an authenticated key agreement protocol (AK). • Explicit Key Authentication. A protocol that provides explicit key authentication assures each participating entity that the intended other entities have actually com- puted the key. Such a protocol is also called an authenticated key agreement with key confirmation (AKC) protocol.