摘要:With the features of end-to-end QoS, statistical multiplex and centralized network management, PTN plays an important role in a carrier network. SDN is developing quickly, having the characters of intel-controlling, centralized controlling and source-opened. Based on the characters, the necessity of the introduction SDN to PTN and application scenarios of base station and private line were discussed. Technical requirements of SPTN were proposed and the basic functions of SDN with the result of SPTN testbed in Shanghai CMCC were implied. Finally, the evolution road of transferred layer and controller layer in carrier network after the introduction of SDN was discussed.
关键词:software defined networking;packet transport network;controller
摘要:As a combination application of IaaS and SaaS, virtual desktop is more and more widely used. Virtual desktop users enjoy not only remote access whenever and wherever possible, centralized controlling, but also simplified application installations and upgrades. However, there was some disadvantage concerning customer perception, especially in real-time applications. The desktop cloud data center and the access network, as well as the characteristics of desktop traffic and desktop protocol, were analyzed, an intelligent strategy control mechanism was introduced, where the strategy control center performed to enhance the service quality of access network, whilst the SDN/service chain controller optimized the processing flow in the data center. The solution aimed to enhance the virtual desktop user experience, while promoting the development of virtual desktop applications.
关键词:desktop cloud;virtual desktop;desktop protocol;SDN;service chain;thin terminal;data center
摘要:Currently China Telecom is undergoing a crucial stage of LTE network deployment in a large scale. For Shanghai, the quality of in-building radio signals has a direct impact on the expansion of 4G network subscribers and the brand image of China Telecom in Shanghai. In this sense, how to enhance the in-building users experience in the 4G era is an important subject to be studied. From five perspectives“fast, intelligent, integrated, evolutionary and green”, the thoughts in designing innovative in-building coverage solutions based on indoor distributed pico base stations were demonstrated comprehensively, so as to help operators to quickly construct networks, manage them smartly and reduce the OPEX, as well as to enhance the network integration and to ensure smooth evolution.
摘要:In recent years, the deployment of LTE network has become a hot spot. Based on the introduction of the security design of LTE/SAE, a deep analysis of security risk was made including control plane's congestion, abnormal traffic attack, network convergence which might be brought during the LTE deployment. After that, some solutions were proposed like division of security domain, signaling protection and abnormal traffic protection to provide a security reference for the LTE deployment in China.
摘要:With the development of LTE international roaming, the long time delay for roaming network selection has recently attracted much attention. A LTE international roaming optimization scheme based on equivalent PLMN was investigated. By deploying the scheme in China Mobile Shenzhen Branch and HongKong Branch LTE networks at frontier ports area, UE can do reselection(in idle mode)and redirection(in connected mode)between cells from different operators across the boundary. The average no service time across the boundary shortened from 90 seconds to 5.96 seconds, the customer's international roaming perception was greatly improved.
关键词:LTE international roaming;equivalent PLMN;network selection
摘要:An architecture and solution of lightweight TURN(TURN-Lite) which was suitable for C2C communication scenarios in complex network environment was described. It could simplify the communication processes used by current TURN solution and made full use of the data conversion and transfer capability of distributed data transfer devices(such as CGN/CDN)which had already deployed in current network, opened up network capabilities and provided efficient data transfer services for C2C communication applications developers.
摘要:It was focused on the construction of intelligent perception ability in IP network. Firstly, multi-level IP network perception technology and its current situation were analyzed. Secondly, perception technology application of large-scale network were discussed. Finally, some key problems in building perfect perception capabilities of operators' network were analyzed, trying to explain perception system construction to readers from practice and operable perspective.
关键词:intelligent perception;DPI system;linkage of perception and control;big data analysis
摘要:Focusing on poor configurability, user-unfriendliness, exclusivity, difficulty in supporting large scale deployment of new network architectures, an approach in incrementally deploying the CoLoR future internet architecture was proposed. In particular, the research background, the design principles, the main components of the mechanism and specific solutions under a variety of scenarios were described.
摘要:With the development of the internet, new network architectures and new protocols are emerging. But because of the the inflexible circuits of traditional network devices, the experiment and deployment of new functions are limited. To dealing with this problem, a reconfigurable and evolvable platform for network function innovation was proposed, which could adapt to the demand of network services by orchestrating functional modules in software plane. Then, configurable meta operation unit was used as data processing packet in hardware plane. Finally, the application prospect of the proposed innovation platform was given combined with two use cases.
摘要:Named data networking(NDN)-a future internet architecture replacing hosts with named data as the core objects in the network layer and natively supports single producer- multi consumer multicast application pattern. However, the support of multi-producer application in NDN is still an open problem. MCKite-a multi producer multicast scheme in NDN was proposed. MCKite utilized rendezvous mechanism and stated in pending interest table (PIT)to construct paths to producers. MCKite made topological positions of producers transparent to other producers and consumers, so that routing/forwarding information bases didn't need to be created beforehand or be updated which reduced the complexity of protocol. MCKite was applied to an improved multi-producer data synchronization protocol and had been implemented in ndnSIM. Experiments show that MCKite has shorter stretch and less traffic cost compared to previous work.
关键词:named data networking;multicast;multi-producer;rendezvous
摘要:Content-centric networking(CCN)is a novel network architecture which presents new challenges for the design of routing. Aiming at the characteristics of CCN, a temperature field based routing(TFBR)algorithm was proposed. This scheme introduced the conception of temperature fields in physics into CCN and applied a finite element method(FEM), which is one of numerical analysis techniques, to assign a temperature value to each node of CCN in a distributed way. Simulation results show that TFBR can adequately utilize the cache in CCN nodes and decrease the network average delay while improving the performance of load balancing.
关键词:content-centric networking;routing;cache;temperature field
摘要:The continuously increasing demand of wireless communications impels the fast development of the next generation wireless communication technology. The 5G communication technology, which scheduled to be commercialized in the year beyond 2020, is still on its earlier stage. Based on the development history of wireless communications, the latest trend in the development of the wireless communications at home and abroad was presented. In order to solve the shortage of spectrum resources and improve the capacity of system, two key technologies of physical layer(millimeter-wave communications and massive MIMO)were introduced and remarked. Furthermore, the scenarios and development trend of 5G mobile communication systems in the future were also described.
摘要:Power line communication(PLC)is playing a more and more important role in the smart grid(SG). Apart from conveying information, to reconstruct the topology of the network is also very critical. By modeling the power line network as a tree structure and making full use of the property of“through the network”of PLC signal,it is possible to get the knowledge of the topology of network. The PLC channel model was considered and the topology of PLC network was reconstructed by taking advantage of the signal of the transmitter and receiver. The algorithm of matrix pencil and dynamic network reconstruction algorithm was performed. The simulation results show that both algorithms can reconstruct the network topology accurately with a high probability.
摘要:A large number of “cell-edge area”can arise when deploying a variety of low-power base stations in heterogeneous networks, this can affect the property of edge users. So a cell selection algorithm for edge user was proposed, by using the transmitting end to precoding to suppress interference and improve user received signal-to-interference-plus-noise-ratio(SINR). According to the current number of user in the cell, dynamically adjust the reference received signal added bias to the picocell edge users, to avoid edge users accessing heavy loaded cells. The simulation results show that, compared with the reference algorithms, the proposed algorithm can effectively reduce the load of macrocells, balance the load between different picocells and improve the throughput and resource utilization of the light load picocells.
摘要:A resource allocation algorithm for the downlink of multi-user OFDM system with optimized fairness was studied. Firstly, assign the subcarriers to users with the constraint on proportional fairness and the water-filling algorithm was used in this process for the power allocation of each subcarrier. Then update the bits and power for each subcarrier of all the users using greedy power allocation to achieve higher data rates and power efficiency. Simulation results show that the proposed algorithm improves the capacity of the system while ensuring the performance of fairness better compared with the algorithm in[10]. To[12], the fairness is considerable improved with a little loss of capacity.
摘要:The problem of effective throughput of multiple secondary users access to the spectrum of primary user in the cognitive multiple access channel under collision constraints and imperfect channel state information was discussed. Effective throughput was defined and used as the performance metric for secondary users under opportunity spectrum access(OSA). The channel quality information was considered and limited number of channel samples were used to estimate the parameter of unknown channel quality distribution and the performance of secondary users under imperfect sensing was analyzed. The performance of secondary users under perfect sensing and imperfect sensing was compared by simulations. Moreover, the validity of proposed access strategy was verified by comparing it with other algorithm.
摘要:Due to the powerful capacity of information processing, on-demand and elastic service model, and enhanced security, cloud computing has become the future of military information system. At first, the conception and feature of cloud computing security was discussed. The current situation of research and application in military cloud security was analyzed. The objective of information assurance with military cloud was proposed on this foundation, then the architecture of information assurance with military cloud was structured, and the main modules of this architecture were analyzed in-depth. Lastly some key research opportunities were listed.
摘要:For traditional image fusion method results in loss of texture detail, a block compressed sensing image fusion algorithm in contourlet domain with a shift invariant and anti-aliasing ability called Contourlet_BCS was proposed. Contourlet_BCS introduced contourlet transform into the sparse representation step of compressed sensing since its remarkable feature of articulating the texture and edge information, meanwhile, the low-frequency coefficients fused by weighted rule of regional energy and high-frequency coefficients based on the weighted fusion rule by generalized Gaussian distribution model were also used. Finally, the high quality image can be reconstructed by smooth projection Landweber iteration method under the compressed sensing framework. Experimental results show that the image fused by Contourlet_BCS was better than the traditional method and the fusion image texture clear and had more abundant edge details.
摘要:Through a in-depth study about the reason of network class imbalance, a method called SMOTE was chosen over the data set sampling preprocess, making full use of the advantages which is high accuracy of traffic model feature matching identification and sorting out the encrypted SSL flow, and then using the clustering method and the SVM based on mutual information classification method to further identify SSL encryption specific application, like HTTPS/POPS etc. The hybrid method effectively combines the advantages of static feature matching and machine learning methods,to achieve the balance of classification method on accuracy and speed.
摘要:Now millimeter wave communication and large scale MIMO, 3D MIMO technology have become the research hotspot in the field of mobile communication. IEEE 802.11ad channel model, which is widely concerned in MIMO 3D scenario, is the empirical based on the measuring of the channel. However, ray tracing model belongs to the deterministic model. IEEE 802.11ad channel model and ray tracing channel model were introduced. Then the method of IEEE 802.11ad channel model and ray tracing channel model were simulated in the indoor scenes and the simulation data was counted that the comparison results of TOA, DS, AZIMUTH and AS were obtained. It turns out that both of the two channel models can be modeling for the indoor scenes correctly. But the two models also exist certain differences.
摘要:For the issues that the user remote security authentication for wireless sensor network(WSN), and the defects of the existing schemes, a remote user security authentication scheme of using smart card for WSN was proposed. The mutual authentication between the user, the gateway nodes and sensor nodes was used to verify the legitimacy of users and nodes. This scheme combines mutual authentication and dynamic identity to resist the impersonation attack, smart card stolen attack, distributed denial of service attack, dictionary attack and replay attack. At the same time, the user information was provided anonymous protection, and the user could change the password. The performance comparison results show that the proposed scheme has high security performance and small computational cost.
摘要:Firstly, the future framework of 5G spectrum was analyzed based on the application scenarios suggested by the ITU-R recommendation on 5G vision. Next, from the aspects of spectrum requirement, candidate band and sharing study, the core contents of 5G spectrum work and the difference of 5G spectrum and previous research were discussed. Then, by fully investigating the current research development of 5G spectrum, the future research area was proposed. Finally, the impact and challenges on radio management work were put forward.
摘要:Based on the telecom operator mobile network topology, whereas the requirements of secure service for network information security, the key technologies such as convergence diversion, security audit, user association analysis, etc, were analyzed. The architecture of audit analysis platform was described, and some advice for the constructing of audit analysis service platform was given.
摘要:With the prosperous development of information technologies and popularity of information-based on a global basis, public application and service of cloud computing has become a trend and inevitable part of enterprise growth.Only an enterprise is speeding up the process,which is playing an increasingly important role in the enterprise growth. The security status of public cloud computing was firstly analyzed. Several important technologies were introduced, particularly concerning their dominant positions and inferior strengths. Finally, according to the in-depth research analysis and practical strategies,the protection measures for public cloud computing have been proposed.