基于OMA DM标准的移动终端管理系统的设计

基于OMA DM标准的移动终端管理系统可以提供更方便、更有效、更快捷的终端管理方式,并可以为运营商决策、目标营销、网络优化提供支持。本文结合中国移动增强售后服务平台的建设,介绍了基于OMA DM标准的终端管理系统的设计,并结合现网中存在的实际问题给出了解决方案。     

OMA DM软件的架构设计

OMADM协议是开放移动联盟（Open Mobile Alliance）为了解决日益繁多和复杂的售后问题而制定的一套用于服务器和终端之间进行通信的协议族,包括引擎协议以及特定的应用协议,通过相应协议的实现就可以完成终端信息采集,固件更新,软件组件管理以及数据备份恢复等多种业务,并且借助此网络可以更加方便地推行运营商的新业务,例如在线游戏、在线购物等。本文在TD_SCDMA网络下采用服务器-客户端的思想分析了OMA DM系统的架构,并且对服务器与客户端软件进行了详细的设计,特别是对它们内部的各个组件进行了功能说明。最后结合目前流行的android手机操作系统对DM客户端在android上的实现进行了分析。     

The Open Mobile Alliance Digital Rights Management [Standards in a Nutshell]

The Open Mobile Alliance (OMA) is an industry forum with nearly 400 members representing the entire mobile industry value chain, including the telecommunications, information technology, and content industries. The OMA focuses on developing market-driven, interoperable mobile service enablers for the rapidly converging communications, entertainment, and media worlds. OMA digital rights management (DRM) systems are important examples of such enablers. Although they have been developed for the mobile market, these systems assume network and bearer-agnostic delivery of the content over Internet protocol (IP). This assumption makes OMA DRM systems suitable for use in any environment where the content is delivered over IP, which is true of a very wide array of applications. In this article, we present an overview of the OMA DRM systems and describe their most important features     

NAT Issues in the Remote Management of Home Network Devices

Currently, many customer devices are being connected to home networks. For this reason, it is expected that device management capabilities will be a powerful instrument for the service provider to cope with high maintenance costs, security concerns, and management issues related to home networks. Through DM, the service provider could provide valuable services such as auto-provisioning, remote configuration, firmware and software updates, diagnostics, monitoring, scheduling, and fraud management. However, network address translators that are widely deployed in the home network environment prohibit DM operations from reaching user devices behind the NAT. In this article, we focus on NAT issues in the management of home network devices. Specifically, we discuss efforts relating to standardization and present our proposal to deploy DM services for VoIP and IPTV devices behind NATs. By slightly changing the behavior of Simple Network Management Protocol managers and agents and by defining additional management objects (MOs) to gather NAT binding information, we could solve the NAT traversal problem under a symmetric NAT. Moreover, we propose an enhanced method to search for the UDP hole binding time of the NAT box. For evaluation, we applied our method to 22 randomly selected VoIP devices out of 194 NATed hosts in the real broadband network and achieved a success ratio of 99 percent for exchanging SNMP request messages and a 26 percent enhancement in determining the UDP hole binding time.     

嵌入式OMA-DM系统架构及关键技术研究与设计

OMA-DM是OMA组织定义的一套用于移动与无线网络的终端管理协议。研究了OMA-DM协议在嵌入式终端设备中的实现方案。首先,详细分析了DM协议特点及会话流程,再根据嵌入式终端设备特性,采取模块化架构设计,阐述了DM协议与MMI、EFS、协议栈之间的接口关系,DM tree及会话流程等关键技术实现过程。该方案充分考虑了嵌入式系统平台资源,在降低开发难度的同时提高了系统可移植性。     

P-MIP: Paging Extensions for Mobile IP

As the number of Mobile IP users grows, so will the signalling overhead associated with Internet mobility management in the core IP network. This presents a significant challenge to Mobile IP as the number of mobile devices scale-up. In cellular networks, registration and paging techniques are used to minimize the signalling overhead and optimize the mobility management performance. Currently, Mobile IP supports registration but not paging. In this paper, we argue that Mobile IP should be extended to support paging to improve the scalability of the protocol to handle large populations of mobile devices. To address this, we introduce P-MIP, a set of simple paging extensions for Mobile IP, and discuss the construction of paging areas, movement detection, registration, paging and data handling. We present analysis and simulation results for Mobile IP with and without paging extensions, and show that P-MIP can scale well supporting large numbers of mobile devices with reduced signalling under a wide variety of system conditions.     

基于移动设备的Ajax技术的研究与应用

随着移动终端更多的和互联网连接,传统方式开发的基于移动设备的Web应用无法较好地解决无线网络中存在的处理并发请求效率低、传输延迟等问题。文中针对这些问题提出叫做“Mobile Ajax”的框架,这个框架将Web2．0时代的中间件技术和成熟的网络技术应用到移动设备的Web开发上,通过优化客户端和服务器端数据传输,很好地解决了web应用程序在移动设备上的传输效率和延迟问题。     

移动终端管理技术的研究

主要研究了基于OMA标准的终端管理系统技术框架、具体实现和业务流程，并对当前终端管理中存在的问题进行了分析。     

Transmission in mobile cloudlet systems with intermittent connectivity in emergency areas

The recent development of Mobile Cloud Computing has helped in solving numerous real-life problems. The rate of growth of mobile devices has been increasing at a very high pace. Mobile devices have made substantial contributions in managing emergency situations. Owing to the mobility of mobile devices, cloudlets, and their intermittent connectivity, it may become very difficult to handle emergency situations. To address this problem, a transmission model is proposed for mobile cloudlet systems, where a mobile device is used to designate a cloudlet by using the Borda scores Method and the mobile device can offload a part of its application to this cloudlet. The simulation results demonstrated that the proposed work makes a significant comtribution toward alleviating the problems associated with emergency situations.     

基于移动agent的SNMP网管性能研究

本文针对SNMP网管所存在的问题,基于移动agent技术构建了一个与平台无关的运行环境,利用SNMP移动管理者和代理群实现动态的软件部署模式和多样的网管方式,使SNMP网管适应不同类型的被管设备和不同层次的管理需求,既兼顾已有系统,又提高网管性能.实验表明,移动agent技术能够为SNMP网管带来快速、灵活和高效的管理过程.     

A scalable network-based mobility management framework in heterogeneous IP-based networks

This paper proposes a mobility management scheme to provide a mobile node with high-quality handovers among heterogeneous wireless access networks. The proposed scheme employs a signaling architecture to support fast and reliable delivery of control messages by separating a control plane from a data transport plane in the core network. The proposed scheme is based on the network-based mobility management framework which requires the minimum modifications on terminal devices. With interaction between Layers 2 and 3, the proposed scheme accelerates the handover control procedures. It also enables a mobile subscriber to select a target network for a vertical handover with consideration of not only wireless signal strength but also user preference and quality-of-service status. The proposed scheme addresses the well-known problems of the Mobile IP-based approaches, triangular routing and bottleneck at the home agent, since it establishes a data tunnel for a mobile node along the shortest path between two different access networks. The simulation and experimental results indicate that our scheme provisions more efficient performance than the existing approaches in terms of handover latency, data packet loss, data delivery latency and load balancing.     

Fast and scalable wireless handoffs in support of mobile Internet audio

Future internetworks will include large numbers of portable devices moving among small wireless cells. We propose a hierarchical mobility management scheme for such networks. Our scheme exploits locality in user mobility to restrict handoff processing to the vicinity of a mobile node. It thus reduces handoff latency and the load on the internetwork. Our design is based on the Internet Protocol (IP) and is compatible with the Mobile IP standard. We also present experimental results for the lowest level of the hierarchy. We implemented our local handoff mechanism on Unix-based portable computers and base stations, and evaluated its performance on a WaveLAN network. These experiments show that our handoffs are fast enough to avoid noticeable disruptions in interactive audio traffic. For example, our handoff protocol completes less than 10 milliseconds after a mobile node initiates it. Our mechanism also recovers from packet losses suffered during the transition from one cell to another. This work helps extend Internet telephony and teleconferencing to mobile devices that communicate over wireless networks. This revised version was published online in June 2006 with corrections to the Cover Date.     

Highly Secure Mobile Devices Assisted with Trusted Cloud Computing Environments

Mobile devices have been widespread and become very popular with connectivity to the Internet, and a lot of desktop PC applications are now aggressively ported to them. Unfortunately, mobile devices are often vulnerable to malicious attacks due to their common usage and connectivity to the Internet. Therefore, the demands on the development of mobile security systems increase in accordance with advances in mobile computing. However, it is very hard to run a security program on a mobile device all of the time due the device's limited computational power and battery life. To overcome these problems, we propose a novel mobile security scheme that migrates heavy computations on mobile devices to cloud servers. An efficient data transmission scheme for reducing data traffic between devices and servers over networks is introduced. We have evaluated the proposed scheme with a mobile device in a cloud environment, whereby it achieved a maximum speedup of 13.4 compared to a traditional algorithm.     

WDTF: A Technique for Wireless Device Type Fingerprinting

In this Work, a technique for wireless device type fingerprinting has been introduced. The technique utilizes the information that revealed as a result of the homogeneity in devices of the same make and the heterogeneity in devices of a different make. The diversity in devices of different make is due to different device hardware compositions and the variations in their management capabilities. We apply the statistical technique on network traffic to create unique, reproducible device signatures. We demonstrate the efficacy of our technique on network traffic captured in different scenarios. We have used a total of 300 devices types representing a wide range of device classes. In the experiment, we have used more than 1.5 GB of filtered traffic for analysis and performance evaluation. We measure the performance of the technique by considering the accuracy of device type detection. The results obtained are promising with a higher detection rate than its counterparts.     

Adaptive delivery of video data over wireless and mobile environments

We present an architecture for the adaptable delivery of video data under variable connection characteristics and into devices of variable capabilities. The main application of the proposed architecture is video delivery in wireless and mobile environments. The architecture is based on the Universal Multimedia Access concept and the MPEG‐7 standard. Based on the network and the mobile device, as well as constraints imposed by user preferences and the multimedia content, video is delivered through a careful application of a combination of off‐line and on‐line reductions to the video stream. We present our architecture and describe an implementation of a system based on the architecture. We present basic performance evaluation results to quantify the merit of our approach. Copyright © 2002 John Wiley & Sons, Ltd.     

Minimizing the Handoff Latency in Ad-Hoc Networks When Streaming Media to Mobile Devices

The number of mobile devices connecting to networks independently of a fixed point of attachment is increasing. These wireless networks differ in bandwidth, size and location of the coverage area, access costs and network characteristics. Mobile multimedia devices such as PDA's, palmtops and laptops will also vary greatly in size and processing power. The common denominator however, is that all these devices will require the optimal delivery of networked multimedia data.One interesting problem is the delay imposed upon mobile receivers when switching between wireless cells. We provide a solution to this in the form of an extension of Mobile IP's hand-off algorithm. Our solution involves the exploitation of mobility prediction to predict a mobile terminal's future location based on its previous history (i.e., the last cell that it has been in) and for the media stream to be already present and cached by next cells base station ready for receiving by the mobile device.We cater specifically for continuous media applications, which can be especially effected by severe degradation in quality due to movement between cells. We present the results of a series of simulations of the Mobile IP++ protocol, which demonstrate the effectiveness of the ad-hoc protocol when mobile hosts move in predictable patterns between cells.     

A framework of handoffs in wireless overlay networks based on mobile IPv6

Although there are various wireless access network technologies with different characteristics and performance level have been developed, no single network that can satisfy the anytime, anywhere, and any service wireless access needs of mobile users. A truly seamless mobile environment can only be realized by considering vertical and horizontal handoffs together. With the advantages of Mobile IPv6, a more comprehensive and integrated framework of heterogeneous networks can be developed. In this paper, we discuss the issues related to handoffs including horizontal and vertical handoffs. We present a scheme for integrating wireless local area network and wide area access networks, and propose a micromobility management method called HiMIPv6+. We also propose a QoS-based (quality-of-service-based) vertical handoff scheme and algorithm that consider wireless network transport capacity and user service requirement. Our prototype evaluations and the simulations show that our framework performs as expected.     

使用移动Agent技术的网络管理

当今大型的通信网络往往集成了来自多家厂商的网络和通讯设备，而基于集中式方式的传统网络管理已难以满足用户的需求。移动ａｇｅｎｔ是能够自动在网络各节点间移动并代表其它实体工作的软件实体，引起了人们广泛关注。文章介绍了有关移动ａｇｅｎｔ的基本概念及其系统实现，并讨论了网络管理中移动ａｇｅｎｔ技术的几个应用实例以表明移动ａｇｅｎｔ是解决异构环境的复杂网管的有效途径。     

Cuckoo: flexible compute‐intensive task offloading in mobile cloud computing

Mobile cloud computing (MCC) is an emerging technology to facilitate complex application execution on mobile devices. Mobile users are motivated to implement various tasks using their mobile devices for great flexibility and portability. However, such advantages are challenged by the limited battery life of mobile devices. This paper presents Cuckoo, a scheme of flexible compute‐intensive task offloading in MCC for energy saving. Cuckoo seeks to balance the key design goals: maximize energy saving (technical feasibility) and minimize the impact on user experience with limited cost for offloading (realistic feasibility). Specifically, using a combination of static analysis and dynamic profiling, compute‐intensive tasks are fine‐grained marked from mobile application codes offline. According to the network transmission technologies supported in mobile devices and the runtime network conditions, adopting “task‐bundled” strategy online offloads these tasks to MCC. In the task‐hosted stage, we propose a skyline‐based online resource scheduling strategy to satisfy the realistic feasibility of MCC. In addition, we adopt resource reservation to reduce the extra energy consumption caused by the task multi‐offloading phenomenon. Further, we evaluate the performance of Cuckoo using real‐life data sets on our MCC testbed. Our extensive experiments demonstrate that Cuckoo is able to balance energy consumption and execution performance. Copyright © 2016 John Wiley & Sons, Ltd.     

P&;P: an asynchronous and distributed protocol for mobile sensor deployment

The use of wireless mobile sensors is of great relevance for a number of strategic applications devoted to monitoring critical areas where sensors can not be deployed manually. Mobile sensors can adapt their position on the basis of a local evaluation of coverage, thus permitting an autonomous deployment. Several algorithms have been proposed to deploy mobile sensors over an area of interest. The applicability of these approaches largely depends on a proper formalization of rigorous rules to coordinate sensor movements, solve local conflicts and manage possible failures of communications and devices. In this paper we introduce P&P, a communication protocol that permits a correct and efficient coordination of sensor movements in agreement with the Push & Pull algorithm. We deeply investigate and solve the problems that may occur when coordinating asynchronous local decisions in the presence of an unreliable transmission medium and possibly faulty devices such as in the typical working scenario of mobile sensor networks. Simulation results show the performance of our protocol under a range of operative settings, including conflict situations and irregularly shaped target areas. Furthermore, a performance comparison between the P&P protocol and one of the best solutions based on the virtual force approach, shows the superiority of our proposal in terms of deployment time, message exchanges and energy consumption.