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Cryptography is widely used to secure data and information so that it is not easily misused by parties who are not interested in the data. One type of cryptographic algorithm is Caesar Cipher and Vigenere Cipher. Both of these algorithms are classic cryptographic algorithms that need to be modified so that they become more optimal in the data security process. The first modification is to modify the Vigenere key using Fibonacci. In general, Vigenere Cipher will repeat the same keyword to complete the number of characters that are lacking so that the number of characters is the same as the number of characters in the plaintext. The second modification is to change or convert plaintext letters into ASCII letters so that the code is more difficult to solve. After the ASCII conversion process is done, the next results will be converted back in Hexa letters. In addition to the two modifications made, the steganography technique is also added by hiding the code behind the media in the form of images. Images that are sampled will be renamed and stored in different places.

Message security in communication is very important to maintain the confidentiality and integrity of messages. The message that is sent must be conveyed in its entirety and only delivered according to its purpose. One Time Pad or OTP is an algorithm that can encrypt messages into ciphertext so that message security can be guaranteed. OTP is a symmetric cryptographic algorithm, that is, the key for encryption and decryption is the same. To perform encryption, the OTP plaintext length must be the same as the key length. This will make it difficult when there is a very long length of plaintext, so the key must also adjust it. OTP keys also have a weakness if a key has been used more than once. Therefore a key builder is needed. In this research, the key generator used is base64. Base64 is used to change the bits of plaintext that will be used by OTP. In this study, base64 can encode plaintext to be used as an OTP key so that it succeeded in making the key generator from base64 encoding.

Electronic mail is a communication model that is fundamental in the era of globalization. Proven on any form of registration data or information requires the presence of email address(electronic mail). The use of email itself cannot be separated from the abuse (such as stelling password and mail spoofing) from some parties so it needs security form in email communication. Communication security on mail server such as ZIMBRA mail server has been well-implemented, such as the use of ssl certificate. But the security is still standard. So, when user and password have been found out by third party, email content will be read easily (in cryptography technique it is called plaintext reading). On research that was conducted with pretty good privacy (PGP) method email communication security was focused on the email content by encrypting mail text along with the attachment file. In a study conducted, using the mail engine Zimbra mail server. Result of research shows that PGP security is able to secure email content whether the text or the attachment, showing difference of attachment file size is bigger on PGP using and change mail header from the standard mail.