According to one embodiment, an end station is provided for coupling to a
communications network and participation in a communications session with
another end station using the network. The end station includes
encryption circuitry including a first linear feedback shift register
(LFSR) and an associated first interconnect mask. The encryption
circuitry is operable to generate an output sequence using the first LFSR
and the first interconnect mask. A first table contains a plurality of
polynomials each corresponding to an available interconnect mask. The end
station is operable to receive a key specifying the first interconnect
mask and to use the output sequence of the encryption circuitry to
encrypt an information stream.