The Research And Implementation Of Active Routing Framework

With the rapid development of modern communication technology and networks, traditional mechanisms can no more satisfy the requirement of new types of network applications.Traditional switching equipments can only accomplish simple processing of packet headers and passive transmission of data. The routing protocols and switching modes cannot be customized according to extra requirements of applications, or renovate in time to adapt the numerous emerging applications.So customers cannot take part in the transmission processes of packets and data, or control the path that packets pass through the network to assure the Quality of Service along the way.Thus, the concept of active network was promoted to solve the inherent problems of existing networks. The nodes in active networks are called active nodes, while the packets in active networks are called active packets. Active nodes not only are in charge of storing-forwarding of active packets, but also provide the user code contained in active packets with executing environments.This thesis was supported by the JiangSu Natural Science Foundation project "Research on the algorithms and protocols in high-performance routing and switching network systems". The research work of this thesis focuses on the active network's support to active routing mechanisms with QoS guarantee, and on how to use active network to realize the QoS-customized active routing.By comparing the similarities and differences of routing mechanisms in active network and in traditional network, this thesis discussed the feasibility and implementing scheme of active routing in active network; extended the active network toolkits-ANTS, including adds an active routing customizing module and unified interfaces which can be called by users in its framework, to make it support active QoS routing; realized and deployed an active routing application in QCAR to validate the rationality and feasibility of this new framework.The main research work and achievements includes the following parts:(1) Compared the similarities and differences of routing mechanisms in active network and in traditional network; pointed out the feasibility and advantages of using the active network to realize the customized routing; analyzed possible implementing scheme.(2) Studied and analyzed the design of several main active network systems; comprehensively surveyed their performance parameters including security, performance, portability and SDK support, and ultimately choosed ANTS as the foundation for the development of our active routing system.(3) Studied the characteristic QoS parameters of traditional network; choosed a proper set ofthem to reflect the main characters of network and the QoS requirements of network flows, and abstracted the QoS routing problem to a multi-restricted routing problem.(4) Studied and analyzed the basic working mechanism of active network toolkit-ANTS; pointed out its deficiency in supporting the active routing, and proposed a scheme to improve on the ANTS framework—QCAR.(5) By extending the database of system statements with QoS parameters, adding an active routing module, and offering the users unified interfaces that support the transfer of QoS requirements, completed the QCAR system which supports different QoS customizing patterns and has the ability to complete the QoS active routing of unicast application.(6) Based on the QCAR system, realized and deployed the user-customized QoS active routing application program—TraceRtApplication.(7) Based on the TraceRtApplication program, through testing the running time of data flows carrying their respective QoS requirements in various network environments of different topologies, completed the function tests of QCAR system, proved the validity and feasibility that QCAR can support the QoS active routing.(8) Developed a new software—AntsManager, which substitutes the graphic interface of QCARsystem for primary (text only) command line operation mode. Users can use AntsManager to set or modify the topology of each experiment, link state values and QoS requirements of packets transmission process. System can automatically create configuration files according to these settings, startup corresponding active routing application program and directly present the routing result of active packets to users in dynamic style.