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Qi Q.,Beijing University of Posts and Telecommunications | Liao J.,Beijing University of Posts and Telecommunications | Wang J.,Beijing University of Posts and Telecommunications | Li Q.,Beijing University of Posts and Telecommunications | Cao Y.,EBUPT Information Technology Co.
Proceedings - IEEE INFOCOM | Year: 2016

The mobile cloud computing (MCC) that takes wireless access network as transmission medium and uses mobile devices as client becomes the newest evolution trends of cloud computing. When offloading the complicated multi-task application to the MCC environment, each task executes individually in terms of its own computation, storage and bandwidth requirement. Due to user's mobility, the provided resources contain different performance metrics that may affect the destination choice. Nevertheless, these heterogeneous MCC resources lack integrated management and can hardly cooperate with each other. Thus, how to choose the appropriate offload destination and orchestrate the resources for multi-task is a challenging problem. This paper decouples resource control of mobile cloud from user plane, where a centralized controller is responsible for resource orchestration, offload and migration. The resource orchestration is formulated as multi-objective optimal problem that contains the metrics of energy consumption, cost and availability. Finally, a particle swarm algorithm is used to obtain the approximate optimal solutions. Simulation results show that the solutions can hit Pareto optimum of resource orchestration in acceptable time. © 2016 IEEE.


Qing S.-D.,Beijing University of Posts and Telecommunications | Qing S.-D.,EBUPT Information Technology Co. | Liao J.-X.,Beijing University of Posts and Telecommunications | Liao J.-X.,EBUPT Information Technology Co. | And 6 more authors.
Ruan Jian Xue Bao/Journal of Software | Year: 2012

Network virtualization allows multiple isolated virtual networks to run simultaneously on a shared substrate infrastructure to provide diversifying services to the end user, solving the Internet ossification problem. However, a major challenge is efficiently mapping multiple virtual networks with different topologies into a shared infrastruture, named the virtual network embedding problem. This paper surveys the current literature primarily according to the composition of the infrastructure. Firstly, the concept and feature of network virtualizations are elaborated, and the corresponding model of virtual network embedding is formulated. Secondly, the latest research progress of virtual network embedding algorithms is reviewed according to the composing way of infrastructure, the integrity of problem space, the number of embedding stage and so on. Finally, the potential future research directions are outlined in the aspects of fairness, scalability, high utilization and trust. © 2012 ISCAS.


Liao J.,Beijing University of Posts and Telecommunications | Liao J.,EBUPT Information Technology Co. | Qi Q.,Beijing University of Posts and Telecommunications | Li T.,Technical University of Madrid | And 5 more authors.
International Journal of Communication Systems | Year: 2012

The network mobility (NEMO) is proposed to support the mobility management when users move as a whole. In IP Multimedia Subsystem (IMS), the individual Quality of Service (QoS) control for NEMO results in excessive signaling cost. On the other hand, current QoS schemes have two drawbacks: unawareness of the heterogeneous wireless environment and inefficient utilization of the reserved bandwidth. To solve these problems, we present a novel heterogeneous bandwidth sharing (HBS) scheme for QoS provision under IMS-based NEMO (IMS-NEMO). The HBS scheme selects the most suitable access network for each session and enables the new coming non-real-time sessions to share bandwidth with the Variable Bit Rate (VBR) coded media flows. The modeling and simulation results demonstrate that the HBS can satisfy users' QoS requirement and obtain a more efficient use of the scarce wireless bandwidth. © 2011 John Wiley & Sons, Ltd.


Qi Q.,Beijing University of Posts and Telecommunications | Liao J.,Beijing University of Posts and Telecommunications | Wang J.,Beijing University of Posts and Telecommunications | Li Q.,Beijing University of Posts and Telecommunications | Cao Y.,EBUPT Information Technology Co.
Mobile Information Systems | Year: 2016

The mobile cloud computing (MCC) that combines mobile computing and cloud concept takes wireless access network as the transmission medium and uses mobile devices as the client. When offloading the complicated multitask application to the MCC environment, each task executes individually in terms of its own computation, storage, and bandwidth requirement. Due to user's mobility, the provided resources contain different performance metrics that may affect the destination choice. Nevertheless, these heterogeneous MCC resources lack integrated management and can hardly cooperate with each other. Thus, how to choose the appropriate offload destination and orchestrate the resources for multitask is a challenge problem. This paper realizes a programming resource provision for heterogeneous energy-constrained computing environments, where a software defined controller is responsible for resource orchestration, offload, and migration. The resource orchestration is formulated as multiobjective optimal problem that contains the metrics of energy consumption, cost, and availability. Finally, a particle swarm algorithm is used to obtain the approximate optimal solutions. Simulation results show that the solutions for all of our studied cases almost can hit Pareto optimum and surpass the comparative algorithm in approximation, coverage, and execution time. © 2016 Qi Qi et al.


Qing S.,Beijing University of Posts and Telecommunications | Qing S.,EBUPT Information Technology Co. | Liao J.,Beijing University of Posts and Telecommunications | Liao J.,EBUPT Information Technology Co. | And 6 more authors.
IEEE International Conference on Communications | Year: 2012

Network virtualization provides a powerful tool to allow multiple networks, each customized to a specific purpose, to run on a shared substrate. However, a big challenge is how to map multiple virtual networks onto specific nodes and links in the shared substrate network, known as virtual network embedding problem. Previous works in virtual network embedding can be decomposed to two classes: two-stage virtual network embedding and one-stage virtual network embedding. In this paper, by pruning the topology of virtual network using k-core decomposition, a hybrid virtual network embedding algorithm is proposed to leverage the respective advantage of the two kinds of algorithm simultaneously in the mapping process. In addition, a time-oriented scheduling policy is introduced to improve the mapping performance. We conduct extensive simulations and the results show that the proposed algorithm obtains more revenue in the long-term run. © 2012 IEEE.


Liao J.,Beijing University of Posts and Telecommunications | Liao J.,EBUPT Information Technology Co. | Qi Q.,Beijing University of Posts and Telecommunications | Qi Q.,EBUPT Information Technology Co. | And 4 more authors.
Computer Journal | Year: 2010

IP multimedia subsystem (IMS) is over IP network architecture, but mobile IP cannot directly support session mobility controlled by session initiation protocol-based signaling. The long signaling delay for session reestablishment in application layer always results in session interruptions during the handoff. Therefore, handoff poses a challenge for quality of service (QoS) maintenance in IMS that targets to offer real-time multimedia applications over wireless mobile networks. The existing approaches to solve this problem depend on the advance resource reservation and the optimization of handoff control. Unfortunately, big cost of the advance resource reservation in neighboring domains is a major problem that leads to a serious signaling load and a waste of wireless bandwidth. To solve this issue, we present an enhanced IMS handoff mechanism (EHM) based on user mobility prediction to save network resources by avoiding multiple useless advance reservations. In addition, to support the heterogeneous access networks in IMS domain, EHM evolves a network selective scheme to utilize the network resources more efficiently. The architecture of EHM and the advance QoS negotiation signaling are also presented. We model the cost, the handoff delay and the session blocking probability for EHM and the previous work. Analytical and simulation results show that EHM can enhance the handoff performance, such as reducing resource reservation cost greatly, decreasing session reestablishment delay and making good use of multiple access network resources. © The Author 2009. Published by Oxford University Press on behalf of The British Computer Society. All rights reserved.


Liao J.,Beijing University of Posts and Telecommunications | Liao J.,EBUPT Information Technology Co. | Wang J.,Beijing University of Posts and Telecommunications | Wang J.,EBUPT Information Technology Co. | And 4 more authors.
IEEE Transactions on Consumer Electronics | Year: 2010

Multi-homed devices equipped with multiple network interfaces can transmit data over multiple access paths simultaneously for high-speed services. One major problem is that the utilization of different paths with diverse delays may cause packet reordering among packets of the same flow. In the case of TCP-like, the reordering exacerbates the problem by bringing more timeouts and unnecessary retransmissions, which eventually degrades the throughput of connections considerably. To address this issue, we propose a Sender-based Multipath Out-of-order Scheduling (SMOS) scheme, which exploits the sending time discrepancy to preserve the in-order packet arrival. The performance of the proposed SMOS is investigated and compared against other schemes. The obtained results demonstrate the outstanding performance of SMOS as it enhances the utilization of aggregate bandwidth while decreasing the probability of triggering 3 dupACKs. © 2006 IEEE.


Qi Q.,Beijing University of Posts and Telecommunications | Liao J.,Beijing University of Posts and Telecommunications | Cao Y.,EBUPT Information Technology Co.
Global Information Infrastructure Symposium, GIIS 2013 | Year: 2013

In the rural and developing areas, it is always difficult to charge a battery. The mobile device that accesses multiple cloud services consumes much power in executing handoff. To solve this issue, we propose an integrated multiple services handoff using the list method which makes all the active services execute handoff together. Analytic model and simulation are developed to investigate the new mechanism. The results demonstrate that the integrated service handoff mechanism can reduce handoff signaling cost, which can efficiently save power consumption for mobile devices. © 2013 IEEE.


Qi Q.,Beijing University of Posts and Telecommunications | Cao Y.,EBUPT Information Technology Co. | Li T.,Technical University of Madrid | Zhu X.,Beijing University of Posts and Telecommunications | Wang J.,Beijing University of Posts and Telecommunications
IEEE Transactions on Consumer Electronics | Year: 2010

Mobile Internet Protocol Television (IPTV) provides users with multimedia content through wireless access technologies whenever they want and wherever they are. However, vertical handover in heterogeneous networks results in long interruption time and large packet loss rate, which poses a challenge for seamless mobile IPTV service. The existing solutions that make use of the heterogeneous access networks to transmit multimedia content have two drawbacks: high bandwidth consumption of the wireless networks and lots of packets loss when a user resides in the overlapped area of the boundary. To solve these issues, we propose a new soft handover mechanism, based on the IPTV server and the consumer electronic devices. The proposed Parallel Soft Handover (PSH) divides the Real-time Transport Protocol (RTP) packets according to the packet loss rates, and exploits different networks efficiently by using parallel transmission. Moreover, the selective retransmission for RTP packets is introduced to reduce the packet loss. Simulation results demonstrate that the PSH can reduce the packet loss rate, as well as obtain a more efficient use of the wireless bandwidth. © 2006 IEEE.


Qi Q.,Beijing University of Posts and Telecommunications | Qi Q.,EBUPT Information Technology Co. | Liao J.,Beijing University of Posts and Telecommunications | Liao J.,EBUPT Information Technology Co. | Cao Y.,EBUPT Information Technology Co.
IET Communications | Year: 2014

Mobile devices are becoming the primary platforms for many users who always roam around when accessing the cloud computing services. From this, the cloud computing is integrated into the mobile environment by introducing a new paradigm, mobile cloud computing. In the context of mobile computing, the battery life of mobile device is limited, and it is important to balance the mobility performance and energy consumption. Fortunately, cloud services provide both opportunities and challenges for mobility management. Taking the activities of cloud services accessing into consideration, the authors propose a service-aware location update mechanism, which can detect the presence and location of the mobile device without traditional periodic registration update. Analytic model and simulation are developed to investigate the new mechanism. The results demonstrate that the service-aware location update management can reduce the location update times and handoff signalling, which can efficiently save power consumption for mobile devices.

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