Abstract: SMTP is a text based protocol and this property of the protocol renders it really insecure as any mail can be compromised if intercepted. Therefore, I have augmented the source code of an open source MTA ,i.e., Haraka to incorporate the public key cryptography using openpgpjs module. Haraka is written in asynchronous JS and is totally based on plugins. For the first time, the client generates a key pair and sends the public key component of the key to the designated server for registration. The registration process follows OTP authentication. Now every client registered on the network has a secret private key and the corresponding public key stored on the server. I have created a server whose sole task is key management. Whenever a client wants to send a mail, it requests the server for the public key of the recipient and encrypts the mail body. The mail is decrypted by the designated client with it’s private key and the pass phrase, which are kept confidential.