Research Of Extraction And Recognition Technology Of The Optical Label Based On Subcarrier Multiplexing

The remarkable growth of Internet traffic has spurred research and development of scalable and high-capacity networking technologies. While the introduction of wavelength-division multiplexing (WDM) has provided increased capacity beyond 10 Tb/s over a single strand of fiber, improvements in switching capacity of Internet protocol (IP) routers have not been as impressive. Optical-label switching (OLS) is a promising technology providing scalability in routing where switching occurs directly in the optical layer without optical-electrical-optical (O/E/O) conversions.This paper provides theoretical and experimental studies of radio-frequency (RF) photonics processing techniques applicable in subcarrier-multiplexed optical-label switching (OLS) communications systems. The paper provides an overview of various label-coding technologies and introduces subcarrier multiplexing (SCM) as an attractive technology for OLS networks. All-optical-label extraction using optical filters, such as fiber Bragg gratings (FBGs), provides an effective means to demodulate the SCM labels without inducing RF fading effects caused by fiber dispersion. Furthermore, the role of fiber nonlinearities in the RF fading effects is theoretically and experimentally verified. The all-optical label extraction and rewriting processes constitute optical-label swapping, wherein 2R data regeneration can take place. Scalable and cascadable OLS systems are feasible by applying viable RF photonics technologies in all-optical-label processing.