An arrangement is provided for performing RC4 ciphering. The arrangement includes apparatuses and methods that pipeline generation of a key stream based on a byte state array, called the S-box, which is initially generated from a secret key shared by a receiver and a transmitter in a network system. The S-box is stored in a storage device which may be a register file with two read ports and one write port. A cache is used to store a number of bytes read from the S-box storage device.