Which of the following types of cryptography should be used when minimal overhead is necessary
for a mobile device?

A.
Block cipher

B.
Elliptical curve cryptography

C.
Diffie-Hellman algorithm

D.
Stream cipher

Explanation:
Regarding the performance of ECC applications on various mobile devices, ECC is the most
suitable PKC (Public-key cryptography) scheme for use in a constrained environment.
Note: Elliptic curve cryptography (ECC) is an approach to public-key cryptography based on the
algebraic structure of elliptic curves over finite fields. One of the main benefits in comparison with
non-ECC cryptography (with plain Galois fields as a basis) is the same level of security provided

by keys of smaller size. Using smaller key size would be faster.