The advent of NFV is a major revolution in the field of networking. The mapping planning of service function chains has an important influence on the performance of NFV, so it has always been the focus of research. Existing algorithms can't consider the problem well with resource consumption and link delay and find the effective mapping path. To address this issue, we propose an aggregation service chain mapping plan based on the improved BAS algorithm. First, we aggregate the service chains with the same start point and end point, then apply the improved BAS algorithm with K-shortest path algorithm(MASFC) to search the best mapping plan iteratively. The experiment result shows that the algorithm can find the effective mapping plan with the restriction of resource. It also reduces the amount of calculation, thus reduces the consumption of computing resource, and has a good performance in network delay and mapping cost.
In this letter, a novel pilot superimposition method is proposed for universal filtered multi-carrier (UFMC) systems to sounding channel. The pilot signals are superimposed onto some special positions in the filter ramps to make sure that the interferences between data and pilot signals are kept relatively low. Simulation results show that the proposed method can estimate channel frequency response (CFR) on the whole bandwidth with a slight degradation of BER performance in the low signal-to-noise ratio(SNR) regime.
Most of the passwords created by individuals, business organisations and other institutions using other software application to ensure the privacy and protection of their data/information according to the research can be hacked by hackers which at the end cause a lot of financial loss and other disparities. In this paper we create password security system using Spark Technology for data privacy and protection. Secondly, we test the created password by selecting data from the various departments in Kumasi Technical University, Ghana, for the experiment to detect if the created password using Spark Technology can be hacked in order to have access to the data selected or not. The actual data selected for experiment are first and second semester examination results of 2016 academic. The password security system created is "spark.authenticate.secret" using Apache Spark Technology to guarantee data protection and privacy.
In real-world traffic data, missing data is inevitable for traffic collection problem and some other reasons. Therefore, it is increasingly critical to complete the whole traffic data. To make full use of hidden spatial-temporal structures of the Internet traffic data, we extend to traffic matrix (user, server) to a three-way tensor (user, server, time). This paper proposed a novel algorithm to recover the missing data, named TSVT (Tucker decomposition and tensor singular value thresholding). We exploit the proposed the Tucker decomposition and low rank tensor completion (LRTC). Based on LRTC, we extend the known singular value thresholding (SVT) to the tensor case, and combine Tucker decomposition to optimize the performance of the algorithm. Based on Internet traffic data, we model two different tensors, and apply our TSVT to infer the unobserved data of the traffic. Furthermore, we apply TSVT algorithm to our Internet data. Numerical experiments on Synthetic data verify our method and the application for completing DPI traffic data proves the effectiveness of the method.
In recent years, many researchers have focused on fiber Brillouin amplifier(FBA) for the higher amplify gain than traditional optical amplifiers, such as Erbium-doped fiber amplifier (EDFA). But the efficiency depends deeply on the relative state of polarization (SOP) of pump and probe signal. In this paper, The SOP of pump and probe signal are considered when trying to get the analytical solutions for the steady-state fiber Brillouin amplification in a long single mode optical fiber. The analytical solutions' validity has been proved by comparing with the numerical results. In the experiment, we screen out different amplified probe power through changing the relative SOP of the pump and probe signal.
