In this paper, we study the coloring problem for the undirected binary de Bruijn interconnection network. The coloring scheme is simple and fast. We propose the coloring algorithm by using the pseudo shortestpath spanning tree rooted at ´0¡¡¡00µ. Each processor can find its color number by its own identity. Then, based on our coloring algorithm, we propose a 1-fair alternator. Our design is optimal. In our design, each processor can execute the critical step once in every 3 steps. Key words: alternator; coloring; de Bruijn graph; phase synchronization