Development of an Algorithm for Physical Layer Impairment Aware Routing in WDM Network

Abstract

A communication system is an entity involving the set of physical equipments meant for information transfer from one place to another. Till 1980s, most of the communication systems implemented electrical transmission technology via copper cables, radio frequency, microwave and satellite links. The invent of lasers stirred focus of research towards implementing optical region of electromagnetic spectrum instead of High Frequency (HF) or Ultra High Frequencies (UHF) as carrier wave. The advantages like long transmission distance, large information carrying capacity, small size, immunity to electrical interference and signal security played a vital role in replacement of copper cable as communication medium. An important breakthrough came with invent of Wavelength Division Multiplexed (WDM) networks further supported by introduction of Erbium Doped Fiber Amplifiers (EDFA). The popularity of computer usage and internet applications resulted in exponential increase in data traffic transferred using optical networks. Recent trend in growth of internet traffic shows that voice traffic being transferred increase approximately 7% per year, while data traffic has been growing at rate much higher. To achieve these higher capacities, many new technological developments were done in the construction of lasers and fibers, installation procedures, network test and monitoring equipments. Implementation of WDM networks having dynamic network provisioning capabilities is sought as one of the possible solutions. WDM network involves modulation and multiplexing of optical carriers of different wavelengths into a fiber for transmission over long distances and has enormously increased the data carrying ability of the network. Theoretically, if the full transmission capacity of WDM be explored, bandwidth of tens of terahertz may be easily achieved. As the infrastructure of present system may easily handle 160 channels over the same fiber, a simple 10 Gbps signal may easily be expanded up to 1.6 Tbps.