Applied Mechanics and Materials Vols. 644-650

Abstract: Theatre intercom system based on SIP has solved the defects of traditional theater scheduling, but it doesn't guarantee the quality of service (QoS). This paper introduced the key technology for SIP-based theatre intercom system, including the fundamentals of VOIP and signaling technology. We analysed the main factors influencing QoS, summarized correlative techniques improving QoS for theatre intercom system, including QoS relevant protocols and QoS guarantee technology on terminals. These technologies can be synthetically used, so as to improve the reliability of theatre intercom system.

Abstract: Campus student credit management system under cloud storage is studied to improve performance of management system. In universities, credit is an important indicator of student achievement, and a direct impact on whether students can graduate. How to manage credit of students, has become a key topic of campus management. To this end, the campus student credit management systemunder cloud storage environmentsis proposed. The relevant principles and hierarchy of cloud storage are elaborated, and storage environment of campus student credit management system is obtained. In these environments, student credit management is achieved. Experimental results show that with the improved algorithm to process campus student credit management under cloud storage, the storage space can be expanded to improve management efficiency, to meet the actual needs of the campus administration.

Abstract: In this paper, an overview and security threats of e-commerce are described.Combining traditional risk assessment method fore-commerce transactions,the assessmentindicatorsneed to be considered in risk assessment of e-commerce transactionsare analyzed, and quantitative calculation method oftransaction riskis given based on cloudcomputing.Moreover,how to detect andassess the riskof e-commercetransactionenvironmentare made simple discussionand assessment. Experimental resultsshow that the algorithmcan effectively reducetransaction risk andprotect the legitimaterights and interestsof users.

Abstract: The Network Time Protocol (NTP) is used to synchronize clocks of various computer devices such as personal computers, tablets, and phones based their set time zones. The network of devices that use these NTP servers form a huge distributed network that attracted a number of attacks from late 2013 towards early 2014. This paper presents a hands-on test of the Distributed Reflection Denial of Service (DRDoS) attack by the monlist command, provides more vulnerability in the protocol, and offers mitigation to these vulnerabilities. A Kali Linux server was used to test the monlist command on its localhost. The results showed that a request with a size of 234 bytes got a response of 4,680 bytes. A busy NTP server can return up to 600 addresses which were theoretically calculated to return approximately 48 kilobytes in 100 packets. Consequently, this results in an amplification factor of 206×. The knowledge of the way the attack can be propagated was an important step in thwarting the attack and mitigating more such threats in the same protocol.

Abstract: Mobile Ad Hoc network is a multihop temporary network composed of a set of mobile intelligent terminals with no center. According to the related questions of mobile Ad Hoc network address configuration, on the basis of the existing application in mobile Ad Hoc network address automatic configuration mechanism, this paper discusses Binary Tree Model-based Dynamic Address Allocation Mechanism. The mechanism dynamically configures a unique address for the nodes according to their relative positions in network topology, reduces control overhead, and with the help of node number, processes network merger and division to effectively address resource management. It has good scalability, and is suitable for mobile Ad Hoc network.

Abstract: In this paper, a novel high-throughput method is proposed to improve the decoding efficiency of the context-based adaptive variable length coding (CAVLC) procedure of H.264/AVC. Due to the data dependency among symbols in the entropy decoding flow, the CAVLC decoder requires large computation period, which dominates the overall decoder system performance. To expedite its decoding speed, the critical path in the CAVLC decoder is first analyzed. This paper presents a double level design for H.264/AVC CAVLC decoding. In the proposed design, we exploit a predict strategy to achieve double level decoding. Experimental results show that the operation period of the proposed architecture can be reduced about 28.3% compare with the tradition CAVLC architecture. The maximum frequency can be larger than 120 MHz, which can support the real time requirement.

Abstract: This paper proposes a distributed integrated quality of service (QoS) multicast routing algorithm, which based on genetic simulated annealing algorithm, for the wireless sensor networks (WSNs).The basic idea is to grade the huge and complicated network, and decentralize resource requirements and the computational overhead of source routing algorithm to the various nodes. In this way, each node just needs to know partial information and make local decisions. In addition, simulated annealing algorithm is introduced into genetic algorithm (GA), whose cooling schedules will be more sophisticated through adjustment of temperature attenuation function, combined with improved adaptive crossover and mutation probability though and heuristic crossover and mutation strategy, which can overcome premature convergence and low searching efficiency in late evolution of the genetic algorithm, also improve evolution speed of the simulated annealing algorithm. The algorithm can meet different QoS requirements of services, and have better performance than the original algorithm.

Abstract: In this paper, it is proposed that Flash can replace game editors to develop mobile games. In an actual project, Flash is used as a graphic editing tool and directly produces together with simple ActionScript codes the data needed by game framework from Fla files, indicating that Flash can replace most of expensive commercial editors and has feasibility and practicability in aided design.

Abstract: Based on telecom operators increasingly urgent demand for intelligent pipeline, this paper has proposed a kind of implementing scheme of traffic recognition system in LTE network. Aiming at the traditional monitoring system with poor user perception and insufficient statistical capacity, we achieved a self - learning refining identification system of application layer services, and further analyzed the characteristic of user behavior in mobile network which relying on the traditional monitoring system and applying current prevailing Internet behavior analysis technologies-deep packet inspection (DPI) technique and focused crawler technology.

Abstract: Network stream analysis is one of the essential applications of industrial research in the era of big data. As the input format of the major massive data application platform--Hadoop, cannot support network stream sufficiently. This paper proposes a feasible optimization design. Firstly, the HDFS block-storage structure and the particular libpcap file format of network stream are considered. Then input files were pre-processed as large as HDFS block-size, and a new data input format called blockPcapInputFormat is achieved by expanding the fileInputFormat of Hadoop. Furthermore, experiments are performed for verifying the proposed design’ effectiveness. Results have shown that the optimization scheme is not only able to accelerate the processing performance of libpcap files effectively, but also suitable for applications where Hadoop parses network stream.