An Authentication Scheme for Personalized Mobile Multimedia Services: A Cognitive Agents Based Approach

Due to the rapid increases in the population of mobile social users, providing the users with satisfied multimedia services has become an important issue. Media cloud has been shown to be an efficient solution to resolve the above issue, by allowing mobile social users to connect to it through a group of distributed brokers. However, as the resource (like bandwidth, servers, computing power, etc.) in media cloud is limited, how to allocate resource among media cloud with brokers becomes a challenge. Media cloud can determine the price of the resource and a broker can decide whether it will pay the price for the resource when there is an incoming multimedia task (simplified as task). A broker can collect the revenues from the mobile social users by providing the multimedia services. Since resource is limited, the price will generally go up as the resource becomes more and more consumed. Therefore, in this paper, by assuming that accepting each task a broker can get a reward (by collecting revenues from mobile social users like online ads, etc.) and it needs pay some price (to the media cloud) for each task in the network, we concentrate on the optimization problems of when to admit or reject a task for a broker in order to achieve the maximum total discounted expected reward for any initial state. By establishing a discounted Continuous-Time Markov Decision Process (CTMDP) model, we verify that the optimal policies for admitting tasks are state-related control limit policies. Our numerical results with explanations in both tables and diagrams are consistent with our theoretic results.

Next generation mobile networks are expected to provide seamless personal mobile communication and QoS. Since the demands for high speed Internet access as well as multimedia service had increased for last mile broadband access, the Scheduling is one of the most important components of BWA systems that affect system QoS provided to users. Priority queuing gives better throughput than the existing scheme. The IEEE 802.16 standard is a rapidly developing technology for broadband wireless access system. It supports QoS and has very high transmission rate. WiMAX is a standard wireless technology which is used to improve internet access and the multimedia services at very high speed to the end user. The purpose of QoS is to provide a definitive connection to the users who are intrested to connect to the WiMAX tower. In this study we propose a scheme to improve the QoS in the WiMAX system by increasing the throughput and decreasing the jitter. This study is based on the use of two scheduling algorithms to calculate the data in the MAC layer in order to provide maximum throughput. Moreover we propose a scheme to calculate the jitter between the various mobile users. The scheme performance is investigated through simulation. Priority Queuing gives better throughput compared to the Random Early Detection. Also jitter is minimized in priority queuing.

When the heavy rainfalls or typhoons occurred, many counties were unavoidable to suffer the debris-flow and flood disasters in Taiwan. Therefore, it is urgently required to obtain and inform the real-time disaster information to display the situation, and it is important for people to design an effective disaster information system to assist the disaster protection and alerting works. To plan and design a Multimedia Escape and Survival System (MESS), which is a three-tier system composed of the mobile users, multimedia server, and disaster decision server, and the system combines mobile communication technology. MESS combines RFID technology, GPS, GIS and GPRS/3G to find out the 4D safety paths and roads in the disaster areas, and the disaster decision is packed as a reusable Web services which can be used in MESS or other systems for reducing the cost and speeding up the efficiency of system development in the future. Mobile users use mobile devices with GPS to locate the longitude and latitude, and transmitting these coordinates to the GIS server. According to the longitude and latitude, the GIS will draw VR map of disaster area using GIS relevant database and show the simulated safety way to users. The MESS can draw the points on the VR map that includes all users' position and announces the best refuge and escape path. The reasoning engine of MESS is used knapsack problem (KP) and the adaptive path algorithm (APA) which consider distance, security, traffic volume, cost, and refuges where RFID readers were installed to infer reason the 4D safety paths and escape routes.

Recent studies on mobility modeling have focused on characterizing user mobility from real traces of wireless LANs (WLANs)and creating mobility models based on such characterization. However, most of the work does not study how user mobility is correlated in time at different time scales. For example, the future APs with which a user will be associated are predicted without the knowledge of when the association will take place and for how long. In this paper, we build a mathematical model for characterizing both steady state and transient behaviors of user mobility in WLANs. Specifically, we mode user mobility by a semi-Markov process, and obtain the transition probability matrix and the sojourn time distribution from the association history of WLAN users available at Dartmouth college [21]. With the steady-state characterization of user mobility in WLANs, we can estimate the long-term wireless network usage among different access points. By comparing the steady-state distributions of semi-Markov models built based on trace data collected at different time scales, we are able to characterize the degree of correlation in time and location.We also perform a transient behavior analysis of the semi-Markov process (that characterizes user mobility), and devise a timed location prediction algorithm that accurately predicts the future locations of users both the future access points they will associate themselves with and the association duration. We demonstrate the utility of timed location prediction, by showing how it can be utilized to predict the distribution of future user ocations with the time information figured in, and redistributing loads among neighboring APs. An improvement of 80% (in terms of load balance) is observed in a wide spectrum of traffic loads in the simulation.

Both of mobile multimedia and mobile Internet are the important development directions of the mobile service. However, it would take great cost by using the high data transmission rate of wireless multimedia communication service. Under the premise of not increasing the investment in hardware, the personalized service could be applied to the mobile service to not only reducing wireless multimedia communication cost but also keeping the quality of mobile service for users. This paper presents a modeling method of mobile phone user profile based on Ontology. This paper founds a model in a method of spatial graph and introduces the theory of interval valued fuzzy sets, brings forward a series of correlative definitions and formulae of founding the model and designs an Algorithm on the Spatial Graph’s Establishment and Updating. Then, it also studies the reasoning technology based on the mobile phone user profile and presents a Reasoning Algorithm on the Mobile Phone User Profile. It should be considered that we have made a useful attempt on the study of founding user profile and forecasting users’ possible requirements.

Today's multimedia content generation and sharing have been dramatically boosted by the deep penetration of broadband wireless accesses and the much improved processing power of smart mobile terminals. Mobile users can now instantly capture and share short video clips (usually of several seconds) anywhere and anytime, and consume them with convenient touch screen operations. The instant video clip sharing has emerged as a mainstream application; such pioneers as Twitter's Vine, Miaopai, Instagram, and Snapchat have seen great acceptance, particularly by the youth community. In this paper, we present an initial study on instant video clip sharing. Taking Twitter's Vine as a representative, we systematically investigate its distinct mobile interface, service framework, and user watching behaviors, revealing how this mainstream multimedia service type differentiates from its traditional counterparts. Our trace measurement and analysis demonstrate that instant mobile video clips have a much shorter lifespan and highly skewed popularity that quickly decays over time. This is further aggravated by the unique screen scrolling operation for video browsing. As such, the download-and-watch scheduling used by existing platforms can hardly achieve quality user experience and cost efficiency. We closely investigate and model the input user gestures for scrolling, including drag and fling , and analyze the scheduling policy, partitioning it into prefetching scheduling and watch-time download scheduling. We develop effective solutions toward both subproblems as well as their integration with screen scrolling. The superiority of our enhancement is demonstrated by extensive trace-driven evaluation.

Integrated Multimedia Personal Communications with Asymmetric Services for Mobile Users in Cellular Systems

The cloud network has the advantages in efficiently offloading the large-scale Internet traffic, which is considered as a promising architecture to provide the satisfactory multimedia services for mobile users. However, most current studies lack the joint consideration of economic and security of services in cloud network. In this paper, a novel multimedia service optimization mechanism is proposed hereby to meet the user's requirements mentioned above while guaranteeing the reliability of service. Firstly, a credible scheme is designed to help the mobile users distinguish the reliable cloud providers; Moreover, a noncooperative Stackelberg game model is presented to maximize the profit of each party; Furthermore, the equilibrium of this game is achieved by the methods of backward induction and gradient descent; Finally, extensive simulations demonstrate that our solution has efficient performance in terms of secure service ratio, utility, pricing and service requirement.

Context-awareness has empowered advanced multimedia computing technology to provide user-oriented services and environment. This research aims at achieving a seamless video delivery service concentrating on the user’s mobility patterns during a multimedia streaming service session. Mobility supporting technology providing seamless services are categorized into host mobility and user mobility. The former corresponds to host-level handoff while the latter refers to user-level handoff. In host-level handoff, the influential parameters affecting the quality of video consumption are the total distance between the hosts, the distance for streaming to resume while user is in mobility mode and the screen size of the end host. The interdependency amongst the parameters is evaluated by a user subjective assessment and a befitting video quality model is developed, accordingly. Additionally, the optimal video delivery switching point to enable user mobility based video service is studied based on a quality analysis of host mobility services at varying distances among hosts. This quality model supporting a complete mobilization has a high correlation with the assessed quality and enables an adequate seamless mobility for multimedia service delivery.KeywordsSession mobilitySeamless mobilityMultimedia handoff

Anonymous user authentication always is a paramount job in global mobility network (GLOMONET). In GLOMONET, a mobile user can move from one place to another place causes changes of mobile network from one to another. As authentication server can authenticate only its registered users, it cannot verify other mobile users. Furthermore, in global mobility network, communication channel is public. An adversary of the network can get access of all transmitted messages over the channel. In such a situation, several network security attacks can be initiated by an adversary to decrypt the messages. Therefore, mobile users as well as network provider’s information may come in risk. A robust anonymous user authentication and key agreement technique required to ensure the protection of such information. Several authentication protocols have been designed in GLOMONET in recent years. Unfortunately, most of them are unprotected against various network security attacks. Therefore, in this paper, we proposed a rigid authentication protocol in GLOMONET to overcome all the deficiencies of the previous work. Performance analysis of our protocol shows that it is reliable and even more effective compared to other existing protocols.

Heterogeneous wireless network (HWN) is an overlay structure of different wireless networks (WN). The WNs may differ in terms of coverage, capacity, underlying technology, service types, and network operators. In such a HWN environment, a mobile user (MU) equipped with multi-mode or multi-home terminal always wish to maintain connectivity with a wireless network which can provide best quality of experience (QoE). Similarly, the WN may allow the connectivity only to a MU which can provide highest revenue. This may leads to an event, called vertical handoff, where the MU leaves current WN and connect to another different WN. The conflicting goals of maximizing QoE and revenue simultaneously while performing a VHO necessitates the selection of mutually best MU and WN. Game theory is an efficient mathematical tool to model such situations where specific actions of decision makers lead to mutually conflicting consequences to each other. This paper, using a tutorial style, presented the game theory concepts and its application for VHO, type of games, and game solutions. It proposes, in specific, the noncooperative game formulations for three different VHO situations and their solutions using NASH for HWNs.

Finding prevalent mobile user patterns in large amount of data has been one of the major problems in the area of mobile data mining. Particularly, the algorithms of discovering frequent user's behavior patterns in the mobile agent system have been studied extensively in recent years. The key feature in most of these algorithms is that they use a location log dataset with userpsilas requested services. In this case, some problems occur because they do not consider that mobile user's behavior patterns are dynamically variable as time passes. In this paper, we propose a novel data mining method based on temporal mobile access patterns that can efficiently discover mobile user's behavior patterns. An advantage of our method compactly stores user's behavior patterns according to location log dataset and requested services in memory. Thus, even the information datasets require large shared memory when they store, our approach still provides faster access and consume less memory than existing techniques.

Mining data from mobile network data produced by mobile users becomes a hot issue in recent years. For the growth of these data, how to process and analyze these data becomes a challenging problem. A Spark-based framework is proposed in this paper, which process and analyze real mobile network data. CURE algorithm is implemented in this framework to cluster mobile users' behaviors parallelly, and discover their preferences in mobile network.

With the rapid development of multimedia broadcasting and communication technology, multimedia services in the form of componentized network applications deployed in the ubiquitous computing environments comprised of cloud-edge-end 3 tiers of nodes are coming true. However, the existing works usually assume the application is non-partitioned or the computing environment with multiple resources is strictly hierarchical. In this work, we characterize interconnected function components in a multimedia service with a weighted directed acyclic graph (DAG), which then be accommodated with operation resources, like computing and link bandwidth, from the nodes in the ubiquitous computing environment comprised of center/edge cloud nodes and mobile devices. To solve the resource scheduling problem, which is NP-hard, we propose a reinforcement learning-based method to minimize the execution time of the service. The simulation results show that the proposed approach outperforms other baselines on saving execution time and reduce resource occupation at the same time.

Welcome to First International Conference on Internet Multimedia Computing and Service (ICIMCS '2009). The conference is organized by ACM SIGMM Beijing Chapter and held from November 23 to 25 in Kunming, Yunnan, China. ICIMCS '2009 focuses on a wide variety of key issues and investigates new approaches to tackle problems arising from the fast-growing multimedia data on internet and users' diverse requirement for multimedia service. ICIMCS '2009 is a forum for researchers from the academia and the industry, professionals, standard developers to exchange information on the state-of-the-art of internet multimedia information processing technologies and applications, as well as to identify the emerging research topics and define the future of multimedia information computing from internet. We received 70 papers and only 36 oral presentations are accepted. Two special sessions were also organized by the leading young scientists in this area. We kindly acknowledge the great support provided in the reviewing of submissions by the program committee members. The many useful comments provided by the reviewing process must have been very valuable for the authors' work. We would also like to take this opportunity to acknowledge the National laboratory of Pattern Recognition, Institute of Automation/Chinese Academy of Sciences, Yunnan University, China, for their dutiful logistical support. Finally we would like to thank ACM SIGMM Beijing chapter and National Science Foundation of China for sponsoring this event.