The Router Forwarding Plane With Link Virtualization

Link virtualization technology can split link resource into multiple parts and keeps the need of resource among different users or virtual network. Because of the ability of separation of resources, it has a strong advantages in many ways , such as the support of resource between users , the guarantee of quality of service on virtual link and building isolated virtual networks. Just because the cluster router has so many advantages, it has a very broad space for development. However, in the existing work on link virtualization, the realization of virtual link is still relying on the technology based on network layer technology. The major deficiencies of existing link virtualization technology is the lack of support from network equipment , in particular from the core routers ,which can not meet the need of link virtualization. In order to meet the challenges of need of next generation network architecture , research on the forward plane that providers support for link virtualization has important practical significance and broad application prospects.This paper summarizes the current situation of the link virtualization in the recent years. Base on full investigation for the related research of link virtualization and in-depth analysis of the existing achievements , summarize research status of link virtualization , point out the advantages and disadvantages of the previous work and propose the difficulty and critical issues. Through comparing some solutions based on different hardware and software platform , summarize the key technology of link virtualization.Based on the key technology of link virtualization,advance the network architecture supporting link virtualization and model the instances of virtual links and routers in this architecture to estimate whether the router can provide enough link resources for virtual link instances. Based on the existing forward plane of reconfigurable routers supported by 863 Program and the demand of link virtualization for the router forward plane, this paper has been involved in design of the structure of router forwarding plane supporting for link virtualization the realization of the prototype system.In order to keep the forwarding speed of multi-hops virtual links packet , design an organization of multi-hop virtual link forwarding table based on M-Tire Trees and advance the related algorithms, on the characteristic of multi-hops virtual links look-up process, such as cut-out optimization algorithm, update algorithm and look-up table algorithm. The result of simulation shows that the cut-out optimization algorithm can effectively reduce the space of storing forwarding table and times of memory access.In the last, in order to verify the feasibility of achieving link virtualization on router forwarding plane , this paper realizes POS interface split module based on PPP protocol and the multi-hop virtual link forwarding module based on M-Trie algorithms.In this paper, the above-mentioned work is an important reference in a more high-performance design and implementation of link virtualization technology on router forwarding plane, at the same time it provides a detailed design reference and rich and powerful experimental data in practical application of link virtualization in the high-end commercial cluster routers.