Symmetric NAT Traversal Method for Session Initial Protocol (SIP)

2013 ◽  
Vol 284-287 ◽  
pp. 2835-2839 ◽  
Author(s):  
Kuan Lin Chen ◽  
Shaw Hwa Hwang ◽  
Cheng Yu Yeh

Although the integration of SIP-based systems with a network address translation (NAT) environment has been investigated extensively, SIP-based system operation in symmetric model NAT remains relatively unexplored. This paper studies the application of symmetric NAT traversal techniques to SIP-based systems. This study focuses on following the SIP process, a non-additive service server, and employs standard SIP commands such as “REGISTER,” “INVITE,” and “200 OK” to predict and deliver the IP addresses and port numbers of the local NAT. This study also implements RTP streaming in the client-to-client (C2C) mode. The symmetric NAT traversal method for the SIP increases the direct peer-to-peer connection rate. This approach also avoids the STUN and RTP-Relay server. Experimental results with 50 types of NAT indicate that symmetric NAT traversal performs better than the STUN solution. The RTP-Relay server bandwidth cost is likewise superior to the TURN solution. These finding have important implications for SIP-based system developers and carrier providers.

2018 ◽  
Author(s):  
Juan Sebastian Mejia Vallejo ◽  
Daniel Lazkani Feferman ◽  
Christian Esteve Rothenberg

A short-term solution for the depletion of Internet Protocol (IP) addresses and scaling problems in network routing is the reuse of IP address by placing Network Address Translators (NAT) at the borders of stub domains. In this article, we propose an implementation of NAT using Programming ProtocolIndependent Packet Processors (P4) language, taking advantage of its features such as target-agnostic dataplane programmability. Through the MACSAD framework, we generate a software switch that achieves high performance with the support of different hardware (H/W) and Software (S/W) platforms. The main contributions of this paper relate to the performance evaluation results of the NAT implementation using P4 language with MACSAD compiler.


2016 ◽  
Vol 1 (1) ◽  
pp. 45-52
Author(s):  
Palupi Puspitorini

The aim of this study was to select the best sources of auxin of which it can stimulate the growth of shoots Pineapple plant cuttings. This research is compiled in a completely randomized design (CRD) with 4 treatments and 6 replications. The Data were statistically Analyzed by the DMRT. Level of treatment given proves that no treatment 0%, cow urine concentration of 25%, young coconut water concentration of 25% and Rootone F 100 mg / cuttings. The results showed that cow urine concentrations of 25% and Rootone F 100 mg give the best results in stimulating the growth of shoots pineapple stem cuttings. Experimental results concluded that the effect of this natural hormone were better than the shoots without given hormone.           


2020 ◽  
Vol 27 (4) ◽  
pp. 329-336 ◽  
Author(s):  
Lei Xu ◽  
Guangmin Liang ◽  
Baowen Chen ◽  
Xu Tan ◽  
Huaikun Xiang ◽  
...  

Background: Cell lytic enzyme is a kind of highly evolved protein, which can destroy the cell structure and kill the bacteria. Compared with antibiotics, cell lytic enzyme will not cause serious problem of drug resistance of pathogenic bacteria. Thus, the study of cell wall lytic enzymes aims at finding an efficient way for curing bacteria infectious. Compared with using antibiotics, the problem of drug resistance becomes more serious. Therefore, it is a good choice for curing bacterial infections by using cell lytic enzymes. Cell lytic enzyme includes endolysin and autolysin and the difference between them is the purpose of the break of cell wall. The identification of the type of cell lytic enzymes is meaningful for the study of cell wall enzymes. Objective: In this article, our motivation is to predict the type of cell lytic enzyme. Cell lytic enzyme is helpful for killing bacteria, so it is meaningful for study the type of cell lytic enzyme. However, it is time consuming to detect the type of cell lytic enzyme by experimental methods. Thus, an efficient computational method for the type of cell lytic enzyme prediction is proposed in our work. Method: We propose a computational method for the prediction of endolysin and autolysin. First, a data set containing 27 endolysins and 41 autolysins is built. Then the protein is represented by tripeptides composition. The features are selected with larger confidence degree. At last, the classifier is trained by the labeled vectors based on support vector machine. The learned classifier is used to predict the type of cell lytic enzyme. Results: Following the proposed method, the experimental results show that the overall accuracy can attain 97.06%, when 44 features are selected. Compared with Ding's method, our method improves the overall accuracy by nearly 4.5% ((97.06-92.9)/92.9%). The performance of our proposed method is stable, when the selected feature number is from 40 to 70. The overall accuracy of tripeptides optimal feature set is 94.12%, and the overall accuracy of Chou's amphiphilic PseAAC method is 76.2%. The experimental results also demonstrate that the overall accuracy is improved by nearly 18% when using the tripeptides optimal feature set. Conclusion: The paper proposed an efficient method for identifying endolysin and autolysin. In this paper, support vector machine is used to predict the type of cell lytic enzyme. The experimental results show that the overall accuracy of the proposed method is 94.12%, which is better than some existing methods. In conclusion, the selected 44 features can improve the overall accuracy for identification of the type of cell lytic enzyme. Support vector machine performs better than other classifiers when using the selected feature set on the benchmark data set.


Author(s):  
Sankirti Sandeep Shiravale ◽  
R. Jayadevan ◽  
Sanjeev S. Sannakki

Text present in a camera captured scene images is semantically rich and can be used for image understanding. Automatic detection, extraction, and recognition of text are crucial in image understanding applications. Text detection from natural scene images is a tedious task due to complex background, uneven light conditions, multi-coloured and multi-sized font. Two techniques, namely ‘edge detection' and ‘colour-based clustering', are combined in this paper to detect text in scene images. Region properties are used for elimination of falsely generated annotations. A dataset of 1250 images is created and used for experimentation. Experimental results show that the combined approach performs better than the individual approaches.


2015 ◽  
Vol 1092-1093 ◽  
pp. 972-975
Author(s):  
Jing Yang

According to the problems exist in cyclic utilization of washing wastewater, the coagulation tests utilizing ferric trichloride (FeCl3), alums, poly aluminium chloride (PAC) and polyacrylamide (PAM) are studied, respectively. Experimental results show that PAC was much better than the other coagulants in the removal of LAS and chroma as a single coagulant. Cast 2.5mL PAC(10%) into quantitative washing wastewater, the removal rate of LAS and chroma reach 82.5% and 87.8%, respectively. When mix the every two kinds of coagulants, maintaining the same total amount of coagulant to 2.5mL, cast1.0mL PAC(10%) and 1.5mL alum (10%) into washing wastewater ,the removal rate of LAS and chroma reach 84.1% and 90.0%, respectively.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Ji-Yong An ◽  
Fan-Rong Meng ◽  
Zhu-Hong You ◽  
Yu-Hong Fang ◽  
Yu-Jun Zhao ◽  
...  

We propose a novel computational method known as RVM-LPQ that combines the Relevance Vector Machine (RVM) model and Local Phase Quantization (LPQ) to predict PPIs from protein sequences. The main improvements are the results of representing protein sequences using the LPQ feature representation on a Position Specific Scoring Matrix (PSSM), reducing the influence of noise using a Principal Component Analysis (PCA), and using a Relevance Vector Machine (RVM) based classifier. We perform 5-fold cross-validation experiments onYeastandHumandatasets, and we achieve very high accuracies of 92.65% and 97.62%, respectively, which is significantly better than previous works. To further evaluate the proposed method, we compare it with the state-of-the-art support vector machine (SVM) classifier on theYeastdataset. The experimental results demonstrate that our RVM-LPQ method is obviously better than the SVM-based method. The promising experimental results show the efficiency and simplicity of the proposed method, which can be an automatic decision support tool for future proteomics research.


1979 ◽  
Vol 57 (4) ◽  
pp. 400-403 ◽  
Author(s):  
Anne Le Narvor ◽  
Pierre Saumagne

The ir spectra of mixtures of methyl propionate/water and methyl propionate/Ba2+ in dimethylsulfoxide and in acetonitrile have been recorded in the region of the νCO mode of the ester. Evidence is presented to indicate the presence of different types of complexes; their concentration was determined as a function of the composition of the medium. The spectroscopic results are compared to those from the kinetics of the alkaline hydrolysis in the same conditions. It is demonstrated that the orbital control explains the experimental results better than does the charge density on the carbon of the carbonyl group. [Journal translation]


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