Classified path restoration scheme with hitless protection switching for large-capacity trunk transmission networks

For large-capacity trunk transmission networks, a path restoration scheme is proposed that has several path-classes with different self-healing grades. The proposed scheme is useful for lightening the burden imposed on VP-based ATM trunk networks. To realize the most highly-reliable restoration class, we apply a route diversity hitless protection switching initiated by parity error detection. We also discuss the improvement of bit error rate performance. By using specially fabricated LSIs and memories, successful hitless switching and improved bit error rate in the path signal are experimentally achieved for the first time.