A Bridge Between Editors and Subscribers

When you get this issue, I believe the first question you will ask would be, "Why does it come out late?" Now let me tell you why. As you may have known, TEIC has been handed over to FLTRP and during the transaction there have been some chaos, which is a quite common phenomenon during any transaction, isn’t it? All the contributions have been mixed up and I have to sort them out. I can’t publish an article which has appeared in the previous issues, can I?

User Churn Prediction Hierarchical Model Based on Graph Attention Convolutional Neural Networks

The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications services,the implementation of the number portability policy,and the intensifying competition among operators.At the same time,users'consumption preferences and choices are evolving.Excellent churn prediction models must be created in order to accurately predict the churn tendency,since keeping existing customers is far less expensive than acquiring new ones.But conventional or learning-based algorithms can only go so far into a single subscriber's data;they cannot take into consideration changes in a subscriber's subscription and ignore the coupling and correlation between various features.Additionally,the current churn prediction models have a high computational burden,a fuzzy weight distribution,and significant resource economic costs.The prediction algorithms involving network models currently in use primarily take into account the private information shared between users with text and pictures,ignoring the reference value supplied by other users with the same package.This work suggests a user churn prediction model based on Graph Attention Convolutional Neural Network(GAT-CNN)to address the aforementioned issues.The main contributions of this paper are as follows:Firstly,we present a three-tiered hierarchical cloud-edge cooperative framework that increases the volume of user feature input by means of two aggregations at the device,edge,and cloud layers.Second,we extend the use of users'own data by introducing self-attention and graph convolution models to track the relative changes of both users and packages simultaneously.Lastly,we build an integrated offline-online system for churn prediction based on the strengths of the two models,and we experimentally validate the efficacy of cloudside collaborative training and inference.In summary,the churn prediction model based on Graph Attention Convolutional Neural Network presented in this paper can effectively address the drawbacks of conventional algorithms and offer telecom operators crucial decision support in developing subscriber retention strategies and cutting operational expenses.

一种基于语义的P2P网格资源发现模型

网格环境中资源的有效管理和发现在网格研究中占有十分重要的地位。文章提出了一种基于语义和P2P技术的新的网格资源发现模型——Semantic-basedPeertoPeerGrid(简称SPTOPGrid)。该模型采用P2P技术进行资源检索,每个peer节点都能提供资源描述和某个知识领域的本体库(ontology);采用publish/subscribe模式进行资源分发;利用语义知识库进行资源的匹配,进行智能化的资源搜索,能够适应网格资源的复杂性、异构性和动态性,具有良好的扩展性。

一种CLF芯片与SIM卡芯片连接的方法

在NFC技术中,CLF芯片与SIM卡的连接是一个重要问题,本文提出了一种具有自主知识产权的CLF与SIM卡的通信方法,采用新的调制解调方式,使得S2信号在S1信号高低电平时都能传输,实现单线连接NFC与SIM卡,以及它们之间的全双工通信。通过对该方法进行电路级的设计和仿真,验证了该方法的正确性和稳定性。

Load-balancing data distribution in publish/subscribe mode

To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while receiving data themselves.A dissemination tree is constructed among the subscribers based on MD5 where the publisher acts as the root. The proposed method provides bucket construction target selection and path updates furthermore the property of one-way dissemination is proven.That the average out-going degree of a node is 2 is guaranteed with the proposed LBDD.The experiments on data distribution delay data distribution rate and load distribution are conducted. Experimental results show that the LBDD method aids in shaping the task load between the publisher and subscribers and outperforms the point-to-point approach.

Evaluation of Broadband Network Performance in Nigeria

Broadband provides high speed data transmission to Internet and 4G networks were developed to transform broadband technology with higher data rate and enhanced quality of service. The performance of broadband network in Nigeria in terms of type, purpose and speed was evaluated in this work. Some quarters at Ilesa and Oba-Ile in Akure were chosen as rural areas, while Abuja and Lagos represented the urban areas of the study. Questionnaires were administered among users in these areas randomly. Thereafter, data were analyzed and research questions answered from the analyzed results. The results showed that the majority of the respondents operated on wireless broadband technologies. The download speed is generally above 100 mbps in urban areas and below in rural areas, with MTN having the highest number of subscribers. In addition, most of the Internet surfers download files. With these characteristics, it was discovered that the network operators were deploying 3G systems as broadband instead of 4G systems.

基于P/S消息中间件的数据交换平台的构建

探讨了一个发布/订阅消息中间件InforBroker的体系结构和核心机制,以一个两级数据交换平台建设实例为背景,分析了消息代理机制在数据交换平台构建和信息集成中的特点与优势。

多网融合环境下的HSS部署策略探析

随着各大运营商LTE网络建设大规模展开,多网融合的移动通信核心网建设成为必然趋势。融合核心网将为用户提供传统语音的同时,带来全新体验的高速数据业务。本文旨在研究作为用户数据存储中心及移动性管理实现的重要网元HSS在多网融合环境下的部署策略,通过多种方案的分析对比,探析其网络定位、目标架构以及演进策略。

An SDN-Based Publish/Subscribe-Enabled Communication Platform for IoT Services

Publish/subscribe paradigm paves a way to integrate and serve many scalable, inter-operable Internet of Things(IoT) applications. The increasing IoT applications require new properties of publish/subscribe communication model, for example, strict quality of service(Qo S) guarantees, supporting a large number of widely distributed devices, etc. Software Defined Networking(SDN) enables personalized programming and individualized QoS supports for different applications. The combination of the two will have a good prospect. In this paper, we present an IoT-oriented communication platform which combines the publish/subscribe paradigm with SDN, aiming at establishing an IoT ecosystem to facilitate IoT services/applications accessing internet. We design the interaction logic of topic-based publish/subscribe middleware, and describe the setup and maintenance of topology information as well as event routing in detail, considering the characteristics of SDN. Finally, we exemplify its practicability with a deployed District Heating Control and Information Service System(DHCISS) and validity the effectiveness with some experiments.

基于中间件在企业信息系统中的应用

随着Internet的发展,新一代ERP系统不仅仅是将原有的ERP应用在Web上简单延伸,于是应用服务器成为ERP系统新的中间件需求。无论是ERP系统中模块之间的互通、互操作,还是应用构件的搭建与跨环境的部署和管理,都需要中间件作为基础层次的支撑。

Broadband ＆ Digital Content-Couple Subscriber Cooperative Relaying Networks for Uplink Transmission using Hierarchical Game Approach

Cooperation allows wireless network users to benefit from various gains such as an in- crease in the achieved rate or an improvement in the bit error rate. In the paper, we propose a distributed Hierarchical Game （HG） theoretic framework over multi-user cooperative communication networks to stimulate cooperation and improve the network performance. First, we study a two- user decision making game in the OFDMA based subscriber cooperative relaying network, in which subscribers transmit their own data in the first phase, while helping to retransmit their partner＇s or choosing to freeride in the second phase. Instead of consulting to a global optimal solution, we decouple the cooperation resource allocation into two level subproblems： a user level Nash game for distributed cooperation decision and a Base Station （BS） level coalition game for centralized resource allocation. In the proposed HG algorithm, where mutual cooperation is preferred and total payoff is transferable, we prove it converges to a unique optimal equilibrium and resolve the subcarrier as-signment and power allocation among the couples. Besides, we discuss the existence of the publishing and rewarding coefficients in order to encourage cooperation. Then, we extend the HG to multi-user cases by coupling among subscribers according to the location information. The simulation results show that the proposed scheme with the distributed HG game achieves a well tradeoff between fairness and efficiency by improving the transmission efficiency of adverse users and outperforms those employing centralized schemes.

Cross-Layer QoS Enabled SDN-Like Publish/Subscribe Communication Infrastructure for IoT

Publish/subscribe paradigm is often adopted to create the communication infrastructure of the Internet of Things(IoT)for many clients to access enormous real-time sensor data.However,most current publish/subscribe middlewares are based on traditional ossified IP networks,which are difficult to enable Quality of Service(QoS).How to design the next generation publish/subscribe middleware has become an urgent problem.The emerging Software Defined Networking(SDN)provides new opportunities to improve the QoS of publish/subscribe facilities for delivering events in IoT owing to its customized programmability and centralized control.We can encode event topics,priorities and security policies into flow entries of SDN-enabled switches to satisfy personalized QoS needs.In this paper,we propose a cross-layer QoS enabled SDN-like publish/subscribe communication infrastructure,aiming at building an IoT platform to seamlessly connect IoT services with SDN networks and improving the QoS of delivering events.We first present an SDN-like topic-oriented publish/subscribe middleware architecture with a cross-layer QoS control framework.Then we discuss prototype implementation,including topic management,topology maintenance,event routing and policy management.In the end,we use differentiated services and cross-layer access control as cross-layer QoS scenarios to verify the prototype.Experimental results show that our middleware is effective.

Margin optimization algorithm for digital subscriber lines based on particle swarm optimization

The margin maximization problem in digital subscriber line（DSL） systems is investigated.The particle swarm optimization（PSO） theory is applied to the nonconvex margin optimization problem with the target power and rate constraints.PSO is a new evolution algorithm based on the social behavior of swarms, which can solve discontinuous, nonconvex and nonlinear problems efficiently.The proposed algorithm can converge to the global optimal solution, and numerical example demonstrates that the proposed algorithm can guarantee the fast convergence within a few iterations.

Radio map updated method based on subscriber locations in indoor WLAN localization

With the rapid development of wireless local area network （WLAN） technology, an important target of indoor positioning systems is to improve the positioning accuracy while reducing the online calibration effort to overcome signal time-varying. A novel fingerprint positioning algorithm, known as the adaptive radio map with updated method based on hidden Markov model （HMM）, is proposed. It is shown that by using a collection of user traces that can be cheaply obtained, the proposed algorithm can take advantage of these data to update the labeled calibration data to further improve the position estimation accuracy. This algorithm is a combination of machine learning, information gain theory and fingerprinting. By collecting data and testing the algorithm in a realistic indoor WLAN environment, the experiment results indicate that, compared with the widely used K nearest neighbor algorithm, the proposed algorithm can improve the positioning accuracy while greatly reduce the calibration effort.

A Secure Short Message Communication Protocol

According to the security requirement of the short message service （SMS） industry application, a secure short message communication protocol is proposed. This is an application level protocol constructed on the standard SMS communication protocol using public key authentication and key agreement without the need of wireless public key infrastructure （WPKI）. Secure short message transmission and dynamic key agreement between mobile terminals and the accessing gateway axe realized. The security of the proposed protocol is validated through the BAN logic. Compared with the standard SMS protocol, the effective payload rate of our protocol can reach 91.4%, and subscriber identity module （SIM） tool kit （STK） applications based on our protocol suit well for all kinds of mobile terminals in practical application.

SecSPS: A Secure and Privacy-Preserving Framework for Smart Parking Systems

Smart parking systems are a crucial component of the “smart city” concept, especially in the age of the Internet of Things (IoT). They aim to take the stress out of finding a vacant parking spot in city centers, due to the increasing number of cars, especially during peak hours. To realize the concept of smart parking, IoT-enabling technologies must be utilized, as the traditional way of developing smart parking solutions entails a lack of scalability, compatibility with IoT-constrained devices, security, and privacy awareness. In this paper, we propose a secure and privacy-preserving framework for smart parking systems. The framework relies on the publish/subscribe communication model for exchanging a huge volume of data with a large number of clients. On one hand, it provides functional services, including parking vacancy detection, real-time information for drivers about parking availability, driver guidance, and parking reservation. On the other hand, it provides security approaches on both the network and application layers. In addition, it supports mutual authentication mechanisms between entities to ensure device/ data authenticity, and provide security protection for users. That makes our proposed framework resilient to various types of security attacks, such as replay, phishing, and man-in-the-middle attacks. Finally, we analyze the performance of our framework, which is suitable for IoT devices, in terms of computation and network overhead.

Energy-Efficient Content-Based Routing in Internet of Things

The?convergence of the Internet, sensor networks, and Radio Frequency Identification (RFID) systems has ushered to the concept of Internet of Things (IoT) which is capable of connecting daily things, making them smart through sensing, reasoning, and cooperating with other things. Further, RFID technology enables tracking of an object and assigning it a unique ID. IoT has the potential for a wide range of applications relating to healthcare, environment, transportation, cities… Moreover, the middleware is a basic component in the IoT architecture. It handles heterogeneity issues among IoT devices and provides a common framework for communication. More recently, the interest has focusing on developing publish/subscribe middleware systems for the IoT to allow asynchronous communication between the IoT devices. The scope of our paper is to study routing protocols for publish/subscribe schemes that include content and context-based routing. We propose an Energy-Efficient Content-Based Routing (EECBR) protocol for the IoT that minimizes the energy consumption. The proposed algorithm makes use of a virtual topology that is constructed in a centralized manner and then routes the events from the publishers to the intended interested subscribers in a distributed manner. EECBR has been simulated using Omnet++. The simulation results show that EECBR has a significant performance in term of the energy variance compared to the other schemes.

采用IMSI+ESN寻呼方式规避法用户干扰问题

C网网络中存在与合法用户的IMSI相同但ESN不同的非法卡,当该合法用户作被叫时,如果非法卡先于合法用户回寻呼响应消息,核心网侧会因为非法卡ESN与核心网不一致而拒绝,合法用户因此无法正常作为语音和短信被叫。本文针对这类非法复制卡干扰合法用户正常通信的问题,给出了一种IMSI+ESN综合寻呼解决方案,通过BSC无线侧用户合法性核查后,再向核心侧回寻呼响应消息,规避了非法用户由于率先响应寻呼消息而造成的对合法用户的干扰。应用实践证明,方案有效解决了该类型复制卡干扰问题,保障了合法用户的利益;同时对语音和短信被叫成功率、短信首次下发成功率指标等均有帮助,并能间接降低补卡带来的营销成本。该方案已在四川全省推广应用。

Vega Prime之OpenGL文字显示程序设计

采用Vega Prime与OpenGL混合编程的方法,在Vega Prime虚拟场景中,实现用OpenGL代码显示文字和绘制十字丝。结合实例讨论了Vega Prime与OpenGL混合编程以及OpenGL显示文字的方法。

卫星通信基于Pub/Sub软件的应用研究

卫星通信设备软件中,需要与很多的设备和模块进行交互,这些设备和模块不断产生和消费数据,需要一个实时、高效、可靠、独立性强的通信模型来构建软件架构。而基于Pub/Sub模式的通信模型是一个非常适用于规模化、松耦合的分布式系统中,因此将两者结合是一个非常好的尝试。文中对Pub/Sub模式的通信模型进行了详细介绍,对其3种实现方式进行了优缺点分析,并基于卫星通信应用提出了改进意见。