Lenstra’s method is an effective subexponential algorithm with applications in this field and involves computing points on an elliptic curve over a finite field. (10[7])Diffie and Hellman (10[1])name a protocol (10[1])in this field (10[3])that is used (10[1])to perform (10[2])“exchanges” (10[3])over a channel. (10[2])This field relies on “hardness” assumptions (10[3])such as the discrete (10[1])logarithm (10[1])problem. (10[2])So-called “primitives” like the hash SHA-1 (10[4])are used (10[2]-5[1])as the basis (10[2])for systems (10[2])in (10[1])this (10[1])field. (10[1])A public key (10[1])and a (10[1])private (10[2])key (10[3]-5[2])are used (10[4])in an (10[1])algorithm (-5[1])in this (10[1])field that relies on the difficulty of factoring large numbers, the RSA algorithm. For 10 points, name this branch of computer science that develops (10[2])secure (10[1])communication (10[1])methods. ■END■ (10[5]0[1])