An Implement Of POF Controller And Traffic Management Research

The traditional TCP/IP network has promoted rapid development of the Internet. But with the ever-changing network service model and the rapid growth of high-bandwidth demanding applications, TCP/IP network are working with great pressure. TCP/IP network can’t meet the different requirement of Quality of service (QoS), and the shortest path routing policy will lead to a local link congestion even if there exist s alternative forwarding path in the network. At the ingress to an MPLS domain, label switching routers (LSRs) classify IP packets into forwarding equivalence classes based on a variety of factors. The network can achieve high speed forwarding, path control and Quality of service guarantees. MPLS technology has been widely used to optimize network resource utilization. But in the distribution architecture, the control layer of MPLS network can’t timely get the whole picture of the network information, which makes it hard to improve resource utilization.Software Defined Network (SDN) has the ability to manage global network information, and the programmability of SDN can provide new network services without changing the underlying network infrastructure. Using SDN controller can simplify the implementation of MPLS control layer and help to make efficient traffic management. Protocol Obvious Forwarding (POF) protocol is an extension of Openflow protocol, and network can be more flexible by using the POF. However, the current POF controller is a simple prototype system, which lacks functions to support basic network services.Based on the POF prototype controller, we add device discovery, link discovery, topology management, data forwarding and other basic functions. After finishing the basic functions of the network, we implement the bandwidth guarantee function. We have developed the QoS module in the POF controller. The QoS module can classify the network flows according to the network configuration so that POF network can give priority to specific flows’to meet their bandwidth requirement when links or forwarding device becomes saturation. The POF network can provide QoS guarantee service for specific application or network flow.Furthermore, this article adde traffic management module which provides path allocation and resource allocation functions in the POF controller. We research the path allocation program in POF controller, and solve the path allocation problem by the fair allocation algorithm The switch labels the packet and forwards them by label which can forward the same flow in different paths. On the basis of path allocation we implement a weight-based bandwidth allocation algorithm. Algorithm uses the concept of a fair share to ensure that different network flows have the same fair share. The allocated fair share and weight determine the bandwidth allocate to a network flow. The flow management module provides the fundamental for the DiffServ services based on flows’priority weight.In this artical, the POF controller we have developed is applied to a real network environment, and the relevant experimental results show that:(1) compared with the shortest path allocation algorithm, we improve the overall resource utilization of network links and increase the network throughput; (2) the network flows get their bandwidth positive correlation to their weights, so we achieve fair bandwidth allocation based on weights.