Cryptography with Cellular Automata

This abstract discusses a stream cipher based on a simple one-dimensional cellular automaton. The cellular automaton consists of a circular register with N cells, each having a value a_i equal to 0 or 1. The values are updated synchronously in discrete time steps according to the rule (1a) a ′ i = a i = 1  XOR  ( a i  OR    a i + 1 ) , https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429494093/0a33cab9-73db-4093-bdfe-0051b0103a92/content/eq956.tif"/>