Single-chip 622-Mb/s SDH/SONET framer, digital cross-connect and add/drop multiplexer solution

This paper presents a single-chip all-CMOS solution for 4×OC-3c, OC-12, and OC-12c synchronous digital hierarchy/synchronous optical network (SDH/SONET) framing with integrated serial line interfaces. Outstanding features of this chip are clock and data recovery and fulfillment of ITU-T and Bellcore jitter requirements for SDH/SONET systems, as well as the large range of functions offered. These functions include asynchronous transfer mode (ATM) and point-to-point protocol (PPP) support, as well as built-in native SDH/SONET functions such as digital cross-connect, add/drop multiplexing, and automatic protection switching. In addition, the chip is based on a new scalable modular architecture.