The Rule Forwarding And Control Mechanism Of Openflow Based On Generic Multi-core Processor

The problems of poor flow control ability, weak network management capacity andscalability are gradually appearing in the process of rapid development of the Internet.In order to resolve these problems, many technologies, such as programmable network,virtual network and SDN/Openflow, have been put forward to support the developmentand validation of new protocols and architectures. As a kind of fundamental forwardingabstraction and control mechanism, Openflow has the defects of poor expansibility andtardy performance of look up. This article concentrates on the key techniques of rulemanagement and forwarding of Openflow. Main work and innovations can beconcluded as follows:(1) Aiming at managing complex problem of Openflow rule, we propose a rulemanagement mechanism TRM based on the multi-bit tree. Based on TLV, we organizethe rule into a multi-bit tree which has a height of n and different path lengths.Thismethod can shorten the search time of packets and improve the efficiency of rulemanagement.(2) In the view of the low lookup performance, we design and implement a packetlook up algorithm based on multi core parallel processing. This algorithm is on accountof priority of rules, employs fuzzy look up in internal matching field and combinesfuzzy and precise look up in intra matching field, so as to reduce look up time andimprove performance.(3) Aiming at resolving the counter mutex problem in general multi-coreprocessors, we propose a multi-core parallel counter management mechanism based onthe copy. Establishing a plurality of counter copy which binding with forwardingthreads in the shared area, each forwarding thread only update the corresponding copy.At the same time, we obtain statistical information by the polymerization ofmulti-copies. This method eliminates the locking operation of the shared variables whenmultiple threads access them, and effectively reduce the modification, statistical time.(4) Based on multi-core processors and network processing acceleration engine, wedesign a prototype system of NetMagic-pro, make performance analysis on theprototype system for multi-core parallel packets look up, and identify the effectivenessand performance of new forwarding control mechanisms. The results show that theforwarding control mechanism can effectively support Openflow forwarding.In conclusion, we proposes an efficient Openflow rule management mechanism(TRM) and a packets‘look up algorithm, and designs a prototype system ofNetMagic-pro, which has significant theoretical meaning and practical value to networkinnovation platform researches.