- In this paper we find a secure routing protocol for computer networks, which finds minimum optimum path using homomorphic encryption schemes. We briefly look into the existing homomorphic encryption algorithms. We make use of ElGamal encryption, Elliptic Curve encryption and a privacy homomorphism, which exhibits the property of homomorphism in our new routing protocol. Elliptic curve exhibits the property of additive homomorphism and is computationally faster than ElGamal and RSA. However, the privacy homomorphism using mod operation is computationally much faster than both ElGamal and Elliptic Curve. Using the homomorphic property of these encryption algorithms, we propose three new protocols, which are ElGamal, Elliptic Curve and Privacy Homomorphism to find the minimum optimal path securely. These protocols provide confidentiality. Keywords - ElGamal Encryption, Elliptic Curve Encryption, Privacy Homomorphism, Determining minimum optimal path.