Design And Development Of IP Multicast Protocol Software Test System

In the IP-based data communication network, data retransmission will take up a lotof network resource.As a kind of packet transmission mode between unicast andbroadcast, IP multicast will neither specify the receiver nor transmit the data to all hosts.The sender only generates one copy of data, and there’s no need to make a copy foreach receiver. The sender won’t have to maintain the receiver’s information, since it canuse network router to collect the receiver’s information, and then realize the forwardingand copying of packets according to the correct path.But IP multicast mode also hasdrawbacks, such as poor transmission reliability, packet disorder, difficulties inbandwidth management, the complex end-to-end security and difficult access control. Inevery link of software development, more reliable and regulated software testing andevaluation must be performed so that the commercial IP multicast software is stable,reliable, safe operation.In view of the practical need of the IGMP multicast protocol andPIM-SM multicast protocol of H3C Company, a software testing system is designed anddeveloped. The main contents include:1）Based on the theory of software testing, the function architecture of the softwaretesting system is designed; The content and function of software testing strategy,software testing plan and the demand analysis are expounded; The design architectureof software testing is also presented; The principles, standards and procedures of testcase design are specified. In execution phase of software testing, the testing activities,testing process and problem solving methods are analyzed.2) The basic function, working principles, protocol format and technicalcharacteristics of the IGMP multicast protocol and the interoperability between differentversions of IGMP protocols are analyzed; The process and characteristics of neighbordiscovery mechanism, RP and RPT forwarding tree mechanism, BSR and RP electionmechanism, registration mechanism, switching mechanism and assertion mechanism ofPIM-SM multicast routing protocol are described too. The IGMP protocol lets thenearest router of host distribute data to the specified host, while the PIM-SM protocolcontrols the transmittion between routers from data source to the receiver.3) Based on the IGMP protocol and PIM-SM protocol, the protocol softwaretesting system is developed and verified, software testing strategies are formulated and acomprehensive analysis of the test requirements is performed; Also the test cases and automation scripts are compiled. In the validation of the software testing system, thecorresponding testing environment is set up, and the test and verification of problemsfound in function, performance and automation are conducted respectively, finally thecauses of the problems are analyzed and Suggestions for improvement are given.