Dynamic key generation according to the starting time

The article analyses the problem of data persistence while transmitting the messages and looks into possible solutions. The central part of the article describes the algorithm of data encryption and digital signature algorithm according to the starting time of the session. In the algorithm the session key is symmetrically generated for each pair of subscribers; further the data are encrypted with this key. In its turn the session key is also encrypted with a public asymmetric key of a recipient and with an asymmetric encryption algorithm. Then the decrypted session key with the decrypted message are sent to the recipient. This client employs the same asymmetric encryption algorithm and his/her secret decryption key to decrypt the asymmetric session key. The decrypted session key is used for decryption of the received message. Thus, every time new symmetric keys are generated according to the starting time of a session, which enables high speed of encryption along with an open to public temporary encryption keys transmitting. Besides, the article contains examples of Diffie-Hellman protocol work and the hash-function algorithm MD5. They are used for encryption of generated temporary keys and for transmitting common private key to both clients. According to the suggested algorithm, the prototype of key and signature generation has been created and probated. The article illustrates the stages of Diffie-Hellman and MD5 protocol work. The prototype was tested with the help of a computer and two phones (2013 and 2015 production years).

Diffie-Hellman protocol, MD5-functoin, cryptography, encryption, decryption, digital protection, digital signature, symmetric and asymmetric cryptosystems

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