Research On Resource Abstract Model And Open Control Agent Technology For Software-defined Optical Access Network

As the number of users and traffic grows explosively, the broadband access network is developing toward high bandwidth, full service and easy operation and maintenance. However, there are multiple access modes, strong coupling between the service and the access mode and operation and maintenance difficulties in the traditional access network.In addition, with the popularity and development of Internet business,requirements for customization are growing. All of these problems make the intellectualization become the new development direction of the access network.Software Defined Network (SDN) is a hot topic in the field of network technology. The core point of SDN is to realize the basic network architecture of software programming based on the open control interface. Compared with the traditional network, SDN has the following advantages: separation of control plane and forwarding plane, logical centralized control, open control interface, and network virtualization and programmability.Aiming at the advantages of SDN and the challenges faced by the current broadband access network, the SDN control theory and the OpenFlow protocol are combined with the optical access network to study the network model and data model of the open access network.Based on the theoretical model, completing the design and implementation of open control agent with OpenFlow protocol to shield the differences between physical devices and achieve openness of access platform.The specific research contents are as follows:1. The unified network model and data model of the heterogeneous optical access network are established. The network resources are structured and abstracted by shielding the differences of the physical layer technology and the unified description of the network control capability is achieved. It lays a model foundation for the unified control of the heterogeneous optical access network.2. Aiming at the intellectualization of the optical access network,a dynamic load balancing algorithm based on TWDM-PON is proposed in which the user service level agreement(SLA) is introduced to solve the problem of uneven traffic distribution on different PON branches in the current access network. Through periodic traffic monitoring and matching user SLA to predict user traffic requirements, calculate the ONU allocation scheme and transfer the traffic between different PON ports.The simulation results show that the method can effectively improve the bandwidth utilization and user satisfaction through a small amount of periodic calculation and adjustment.3. The openflow protocol is extended to support the open control of the optical access network equipment. The open control agent module of the optical access network is designed, developed and implemented,and the functional test is completed by the software simulation platform. Test results show that the module can correctly receive and analyze messages according to the extended protocol and map messages to the corresponding processing unit of the simulation device,and verify the feasibility and validity of the module.