Im-OFDP: An Improved OpenFlow-based Topology Discovery Protocol for Software Defined Network

Current controllers use the OpenFlow Discovery Protocol(OFDP) to explore the underlying network topology. For improving the performance and safety of OFDP, an improved protocol Im-OFDP is proposed by taking advantage of minimum vertex cover algorithm. Experiments demonstrate that Im-OFDP outperforms OFDP and OFDPv2 in terms of LLDP packet number, controller CPU load and safety.