Optimizing the Run Time in Mobile Devices

Mobile computing works on the principle of broadcasting so that the information is radiated to everyone within the wave range which increases security threats and cyber attacks replicated quickly and easily. Thus, care must be taken in handling those types of attacks to provide information security while the user roams through different networks with heterogeneous security infrastructure. For that several cryptographic techniques are employed in mobile devices. Among them the public key cryptographic algorithms like RSA and ECC play a vital role in performing security. The basic building blocks of ECC is scalar point multiplication k[P] where k is a scalar and P is a point on elliptic curve. Similarly, in RSA the encryption and decryption is of the form xe mod n where encryption /decryption key. Normally exponentiation operation takes more time than multiplication which takes more time than addition and subtraction. To reduce the time, exponentiations and multiplications are performed by repeated multiplications and additions respectively. To reduce the time further addition chain is used. In order to generate the addition chain nature inspired based algorithms like PSO and SSO are considered in this paper. Using them, the addition chains for exponent of RSA and K[P] of ECC are generated. The encryption/decryption time and energy required for encryption/decryption are also computed and the performance of the cryptographic algorithms in mobile devices are analyzed with and without the incorporation of addition chain.