Key exchange algorithm, often called key exchange protocol, is any method in cryptography that allows the exchange of secret cryptographic keys between two parties, usually via a public communication channel. Hybrid systems use cryptography with a public key to exchange secret keys that are then used in a cryptography system with symmetrical keys. Most practical applications of cryptography use a combination of cryptographic functions to deploy a global system that provides the four desirable functions of secure communication (confidentiality, integrity, authentication and non-contestable). The overall problem with symmetrical cryptography or single-key cryptography is that a secret key must be communicated via trusted couriers, diplomatic pockets or another secure communication channel. If two parties are unable to establish a secure initial key exchange, they cannot safely communicate messages being intercepted and decrypted by a third party who purchased the key during the initial key exchange. The first public public key memorandum of understanding  that meets the above criteria was the Diffie-Hellman key exchange, in which two parties jointly exposed a generator to random numbers, so that an earpiece cannot easily determine what the resulting value is used to create a common key. Cryptography with a secret key (symmetrical) requires the initial replacement of a freed key in a way that is private and guaranteed integrity. If the attack is done correctly, it is avoided. But without the use of cryptography with public keys, we can end up with unwanted key management problems.
In principle, the only remaining problem was to be sure (or at least to be sure) that a public key actually belonged to its alleged owner. Since it is possible to “spoofen” the identity of another in different ways, this is not a trivial or easy problem to solve, especially when the two users involved have never met and know nothing about each other. In 1976, Whitfield Diffie and Martin Hellman published a cryptographic protocol called Diffie-Hellman Key Exchange (D-H) based on the concepts of Hellman`s doctoral student, Ralph Merkle. The protocol allows users to safely exchange secret keys, even if an opponent monitors this communication channel. However, the D-H key exchange protocol does not only address authentication (i.e.dem problem of being sure of the person`s actual identity or `entity` at the other end of the communication channel). Authentication is essential if an opponent can monitor and edit messages inside the communication channel (AKA man-in-the-middle or mitm attacks) and has been addressed in the fourth section of the document.  However, this does not solve the problem, as the reliability of the certification body is still not guaranteed, even for a given person. It is a form of reasoning of authority deception.
Actual reliability requires personal monitoring to determine whether the certificate is part of the certification body and trust within the certification body is required. This is usually not possible. In addition, we examine the following problem of calculating secure functions with trusted parties: Several parties observing correlated data are trying to calculate a function of their collective data. To do this, they communicate interactively via an uncertain communication channel. It is necessary that the value of the function be hidden from an earpiece with access to communication. When is such a safe calculation of a particular function possible? Using the above ceiling, we will deduce a necessary condition for the existence of a communication protocol that allows the parties to reliably restore the value of a given function, while that value is hidden from an earpiece with (only) access to communication. The exponential key exchange often used to describe the Diffie-Hellman key exchange is a secure method of exchanging a secret key