Communication has become an integral part of all beings—both the living and non-living. In most cases, everyone likes to keep their communication personal and secure. Additionally, high-level information is expected to be secure. One of the methods to secure information is encryption, where the information is safeguarded so that it cannot be detected by anybody other than the intended recipient. In an encryption method, key management is essential for proper communication. The exchange of keys may lead to leakage, modification, or change of the keys during transmission. Even in public-key cryptography, the key management problem exists. The proposed method aims to reduce this problem by eliminating key transfers during the encryption-decryption process. The present study uses the IP addresses of the sender and the receiver to securely encrypt the message. The channel is tightly secured in the proposed algorithm as there is no key transfer during encryption and decryption techniques. A table generated by a polynomial function that produces non-linear outputs is used for producing the ciphertext. This ensures that the communication is secure against multiple man-in-the-middle attacks. The complexity of the proposed algorithm is computed and is found to be O(n).