Date Added: Jun 2010
Since the Internet and broadband networks were introduced, emerging applications - such as video on demand, teleconferencing, and high-quality audio transmission - have demanded high-throughput optical-access networks with stringent Quality-of-Service (QoS) capabilities. However, the infrastructure of current access networks suffers from limited bandwidth, high network-management costs, poor flexibility, and low security, which prevent networks from delivering integrated services to their users. Owing to the maturity of optical components and electronic circuits, optical-fiber links have become practical for use in access networks. Passive Optical Networks (PONs) and different multiplexing technologies have been proposed in this context, including Wavelength-Division Multiplexing (WDM), Time-Division Multiplexing (TDM), and Optical-Code-Division Multiplexing (OCDM).