The Design And Implement Of Multi-hop Virtual Link Exchange Mechanism Based On Resilient Label

Network virtualization technology try to divide the resources in the same physical network infrastructure, to let multiple virtual network to be supported. The virtual network flows in different virtual network do not interfere with each other, which can live with the existing network. Network virtualization technology can be used to experiment with new network system structure.Different virtual networks can run heterogeneous protocol stack, which can provide different services for different applications. Therefore, network virtualization technology is a hotspot in current academic research. Many problems can be solved by virtual network which can not be solved in physical network. New network system structure model can be fully experiments in virtual network, many different demand of new business could be achieved. But due to link in virtual network relies on link in physical network, there is a topological tight coupling problem, making the virtual network topology cannot be independent of the physical network topology, which result in the virtual network cannot be created dynamic by the demand of user.In this paper, in order to overcome the above problems, we combine of the network virtualization technology and the existing exchange mechanism, put forward a fast switching mechanism based on multi hop virtual link. Using the concept of label switching in the virtual network, in a multi hop virtual link entrance node to mark a virtual link exit node, intermediate nodes do not deal with the network layer protocol, to exchange multi hop virtual link message rapidly. In order to improve the reliability of a virtual network, on the basis of existing fault restoration scheme, put forward a fast exchange mechanism of multi hop virtual link based on elastic label. The main research results are as follows:1) propose the network virtualization model based on multi hop virtual link. The model's construction improve the existing network virtualization model to meet the need of multi hop virtual link, data plane is divided to forwarding engine data plane and multi hop virtual link data plane, forwarding engine plane shared multi hop virtual link plane, to realize virtual network interface message to be exchanged in multi hop virtual link data plane.2) propose the virtual interface mapping mechanism between forwarding engine data plane and multi hop virtual link data plane. This mechanism can map the physical interface in multi hop virtual link data plane to virtual interface in forwarding engine data plane flexibly.When sending packet to forwarding engine data plane, physical interface need to be mapped to the virtual interface in forwarding engine data plane, when receiving packet from forwarding engine data plane, the virtual interface need to be mapped to a physical interface.3) propose the multi hop virtual link survivability mechanism based on elastic label. The main idea for the mechanism is to provide a backup forwarding path, when a link or node failure, which can send the message back to the upstream node for processing or adopt local processing, so that the data message seem like "resilient", which can improve the reliability of virtual network.4) Using the open source software click to implement a prototype system of the exchange mechanism of multi hop virtual link based on elasticity labels, then test the forwarding performance of multi hop virtual link based on elasticity labels. Through the comparison of the experimental results, analyzes the factors that influence the transfer performance.