Database Establishment And Path Computation Of Three Layers Multi-granular Exhange System For PCE

With the rapid growth of multimedia services,the bandwidth required by IP users keeps increasing and tends to diversify,bandwidth requirements impose higher requirements on the node's computing power.The establishment of the code group routing body based on the path calculation element(PCE)makes the transmission mode more flexible.Due to the limitation of the network information synchronization mechanism,the PCE path calculation often has the phenomenon of link congestion and low utilization of network resources.In order to achieve global network resource sharing and real-time information synchronization,build a traffic engineering database(TED)and a label switched path database(LSPDB),a stateful PCE network architecture based on the establishment of the database is proposed to calculate the optimal path for service requests.This paper studies the establishment of the PCE database,the synchronization mechanism,and the path computation of the statefull PCE.The specific content is as follows:Firstly,in view of the lack of timely synchronization of database information and the protocols selection of optical code information update,this paper expands the related protocols of Open Shortest Path First Protocol,Resource Reservation Protocol,and PCE Protocol.This article defines the message formats collected by the information performance indicators,the direct communication between the PCC and the PCE,and the process of establishing and updating the TED and LSPDB.At the same time,a software model is used to display the database information storage and invocation.Then,for the impact of LSP state information on path computation,this paper proposes a stateful PCE network structure and path computation service flow.The PCEP protocol is extended to define the message format of the LSP status report(update)between PCC and PCE.The statefull PCE completes the constraint optimal path selection by using path computation strategys,such as seizing free LSPs,resource reservation,and macro regulation..Finally,by comparing and analyzing the network convergence time,packet loss rate,and blocking rate performance indicators of the state PCE and the traditional PCE,the network performance advantages of the stateful PCE structure which grasps the global network state and information synchronization are verified.