Information exchange is a prevalent thing in computer networks. The information sent is confidential, and some are ordinary. In sending confidential information, many concerns occur. The sender is afraid of the information being stolen, especially if the information contains confidential data. In sending information, the sender and recipient must know the key or password to be able to read the information correctly. However, sending the key is very deep concern because if others know the key, then the data and information contained in the file will be successfully read. Key exchanges must be avoided. The technique for avoiding key exchange is to use the Three-pass Protocol scheme. This scheme allows the sender and receiver to encrypt and decrypt using their respective keys without having to exchange keys. Three-pass Protocol is a mechanism. There are two algorithms needed in the cryptographic process. The algorithm used is Vigenere Cipher. By implementing the Three-pass Protocol scheme, data security will be more guaranteed.
three-pass protocol, encryption, decryption, Vigenere