Enhanced a TCP security protocol by using optional fields in TCP header

The Transfer Control Protocol (TCP) itself does not guarantee the security of data that it transmits. However, under some circumstances, the security of TCP communication is required, e.g. the client-server communication in banking systems. Nowadays, the source socket layer (SSL) protocol is widely used; however, SSL is based on RSA (a public-key cryptographic algorithm) algorithm, which would require more computational resource. Therefore, an alternative faster solution utilizing symmetrical algorithm (AES) are proposed to achieve these goals: bidirectional authentication, encrypted data transmission and Integrity check. Moreover, use the optional fields in TCP header for carrying related information and introduced a new device SAM (Secure access module) which provides security-related functionalities: encryption, decryption, key-diversification etc