Research On Routing And Spectrum Assignment Algorithm Based On Balancing Energy Consumption With QoS In Flexible Optical Networks

With the rapid development of new network applications,such as high-definition video streaming, cloud computing, big data, data center interconnection and so on, the demand of the network bandwidth is growing in exponential growth trend. However, Due to the full allocation of wavelength capacity for a lightpath, the traditional WDM networks present an inefficiency problem, which cannot adapt dynamic and flexible bandwidth demand. In order to provide finer granularity and enhance the spectral sufficiency of WDM networks, spectrum sliced elastic optical networks have been proposed, and it uses finer spectral interval, providing efficient accommodation of multiple data rates which result in supporting various services. Meanwhile, the energy consumption problem has become increasingly prominent with the increasing services volume and network scale. Improving the utilization of resources is a great challenge to the underlying optical network, and the flexible optical networks technology provides an opportunity for energy conservation research. Therefore, realizing network energy conservation by utilizing the new flexible optical networks technology is worth researching contents. Besides, the physical layer impairments are a main factor which influences the QoS requirement. The relationship between the energy consumption and QoS is interaction. When the optical signal transmits in optical path, the above parameters seriously influence the transmission performance, in the assigning resources process, how to balance taking into account the parameters has an important meaning for improving overall network performance.Based on flexible optical networks, this paper considers the influence of physical layer impairments and uses the energy conservation as a main optimization goal, and the QoS requirement which needs to be met is used as a constraint condition in routing and spectrum assigning process. The main content of this paper are shown as follow:(1) For the energy saving technologies in flexible optical network, this paper firstly analyzes key energy saving technologies from different aspects, and obtaining current network energy saving technologies and disadvantages. On this basis the key energy saving technology in flexible optical network is performed the review, presenting the challenge of energy conservation by multi-factor constraints. Finally, this paper predicts the future trend of energy-efficient research in flexible optical networks.(2) This paper mainly studies the network factors which influence the transmission performance, such as physical layer impairments, etc. For avoiding the physical layer impairments and meeting different QoS requirements, physical layer impairments models and energy modes are established. Meanwhile, for the study of energy-efficient resource assignment algorithm, a link state determination model has been proposed to determine the current network element state, further facilitating energy efficient routing.(3) Based on the flexible optical networks, in order to achieve a balance between the physical layer impairments and energy consumption, according to the link state determination model, this paper has proposed an energy and impairments-aware RSA algorithm. This algorithm fully considers the damaged influence of the physical layer impairments, and the network energy efficiency is improved in the acceptable set up delay by using the minimal network set to bear the basic network service.