DESIGN AND IMPLEMENTATION OF A FIBER DELAY-LINE OPTICAL BUFFER FOR MULTIGIGABIT PHOTONIC SWITCHING FABRICS

Full photonic packet switching fabrics require memories, which are not available today in the optical domain: therefore, an alternative is t he use of optical buffers based on fibers used as delay lines. This le tter reports the optimised implementation of such a buffer operated in a multiwavelength regime and accessed by fast optical gates. The buff er operating principles and two different implementation structures ar e first briefly presented. Then differential delays and influence on b it error rate performance are discussed on the basis of test results w ithin a 4 x 4 photonic packet switching matrix handling ATM cells at 2 .488 Gbit/s. The results demonstrate that fiber delay lines are a simp le, potentially cost-effective solution to implement buffering within highspeed photonic packet switching systems, adopting current optical technology.