Secure Transmission Technology For Optical Networks Based On Multiple Uncorrelated Paths

In recent years,optical fiber communication systems have been evolving quickly in the direction of high speed and large capacity,bringing great convenience to people’s daily life.However,the problem of transmission security has gradually confronted us,and how to achieve secure transmission of optical fiber communication systems has recently become a hot topic.The secure transmission technology of optical fiber communication systems has also gradually developed.Nowadays,there are a large number of security protection schemes for optical networks,such as Optical Code Division Multiple Access(OCDMA),Quantum Cryptography,Chaotic Encryption,and Photonic Firewall.However,the majority of current technologies focus on strengthening security in the physical layer,and there is relatively little research on using control layers to achieve security protection.Multiple uncorrelated paths can heighten transmission security on both time and space dimension.From a spatial perspective,multiple node disjoint paths(NDPs)will be calculated for the service,and a path will be randomly selected for transmitting data.Using node disjoint paths can effectively avoid continuous eavesdropping at fixed positions.On the time dimension,data can be transmitting in a timesegmented way.Given the maximum transmission time of a service,when the transmission time of this service on a certain path reaches the maximum transmission time,the service must switch its routing path to another uncorrelated path to continue transmitting data.If data is transmitted in such a time-segmented manner,network attackers can only eavesdrop on a small portion of the entire service,which obviously improves optical networks’security.Secure transmission based on multiple uncorrelated paths is a crucial technology in elastic optical networks.This paper brings forward using multiple uncorrelated paths to transmit data.In the control layer,multiple uncorrelated paths are established for the service.And the routing path is randomly selected in both temporal and spatial dimensions,which overcomes the effect of eavesdropping in a fixed position and insures the secure transmission in optical networks.The main research work of this article is as follows:(1)Firstly,multiple uncorrelated paths in spatial and temporal dimensions are defined respectively.Then we introduce how they can enhance the security of network transmission,and propose a feasible scheme for using uncorrelated optical paths for transmission.(2)To address the problem of multipath secure transmission,we propose an efficient mixed integer linear programming(MILP)model with the objective to maximize the security of each service while considering the distance of transmission.Since the computational complexity of linear programming model is too high,a heuristic algorithm is proposed to solve this problem in large-size networks.After layering the network,the algorithm selects several uncorrelated paths and then allocates modulation formats and spectrum resources for the lightpaths according to the modulation format algorithm and spectrum allocation strategy.(3)To solve the problem of time-segmented data transmission of dynamic service,the proposed algorithm first uses the maximum flow algorithm to find as many as possible node disjoint paths and then uses the lightpaths that best match the service to allocate spectrum resources.Evaluation results show that in the National Science Foundation Network(NSFNET),the proposed scheme reduces the blocking probability by 56.11%on average compared to Dijkstra+First Fit.