Let C be a device performing computations of a cryptographic protocol. Assume C to have limited computing power, but to have access to another device A with superior capacities. This setting could occur, for instance, with a smart card C and a mobile phone A. We consider the situation where C is supposed to calculate the basic operation of elliptic curve cryptography: the scalar multiplication of a point P on a curve. We investigate whether C's performance could be improved by means of distributed computation; that is, whether C could exploit A's computing power, without compromising the safety of the procedure. We set up three models of computation, varying the demand for C's trust on A's honesty.