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The interworking between heterogeneous third-generation cellular networks and wireless local area networks is one promising evolution approach to fourth-generation wireless networks, which can exploit the complementary advantages of the cellular network and WLANs. Resource management for the 4G-oriented cellular/ WLAN integrated network is an important open issue that deserves more research efforts. In this article we present a policy framework for resource management in a loosely coupled cellular/WLAN integrated network, where load balancing policies are designed to efficiently utilize the pooled resources of the network. A two-phase control strategy is adopted in the load balancing policies, in which call assignment is used to provide a statistical quality of service guarantee during the admission phase, and dynamic vertical handoff during the traffic service phase is used to minimize the performance variations. Numerical results are presented to demonstrate that the proposed load balancing solution achieves significant performance improvement over two other reference schemes.otivated by the ever-increasing demand for wireless communications, the cellular network has evolved to the third generation (3G), for example, the Universal Mobile Telecommunication System (UMTS), which is specified by the Third Generation Partnership Project (3GPP) and is one of the most popular 3G systems nowadays. The 3G cellular network is capable of supporting quality of service (QoS) critical to multimedia services, but at the expense of high complexity and implementation cost. For example, four service classes are supported in the UMTS: conversational, streaming, interactive, and background services. However, the expensive radio spectrum for 3G cellular networks prohibits rapid deployment, and the low bandwidth restricts system capacity. The future fourth-generation (4G) wireless networks need to effectively address these existing constraints and problems. Heterogeneous networking is a promising approach to accelerate the technological evolution toward 4G wireless networks. In recent years, IEEE 802.11 wireless local area networks (WLANs) have proliferated due to a high performance-to-cost ratio. Usually operating at license-free frequency bands, WLANs can occupy a much wider spectrum than the cellular system, and provide data services using a simple medium access control (MAC) protocol. The complementary characteristics of the 3G cellular network and WLANs promote their interworking. Future mobile devices can be equipped with network interfaces to both the 3G network and WLANs at a reasonable price. The dual-mode mobile devices can then enjoy enhanced services in the cellular/WLAN integrated network.The standardization for cellular/WLAN interworking is now underway in 3GPP from the cellular operator's perspective. Six interworking scenarios are defined in 3GPP TR 22.934 to implement 3GPP/WLAN interworking step by step. In the latest Release 6 of the 3GPP standard, the first three interworking levels are included, which support 3GP...

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Abstract-In the interworking between a cellular network and wireless local area networks (WLANs), a two-tier overlaying structure exists in the WLAN-covered areas. Due to the heterogeneous underlying quality-of-service (QoS) support, the admission of traffic in these areas has a significant impact on QoS satisfaction and overall resource utilization, especially when multiple services are considered. In this paper, we analyze the performance of a simple admission strategy, referred to as WLANfirst scheme, in which incoming voice and data service requests always first try to get admission to the WLAN whenever it is available. It is observed that the overall resource utilization can be maximized when the admission regions for voice and data services in a cell and a WLAN are properly configured.Index Terms-Cellular/WLAN interworking, resource sharing, call admission control.

Mobile cloud computing offers an appealing paradigm to relieve the pressure of soaring data demands and augment energy efficiency for future green networks. Cloudlets can provide available resources to nearby mobile devices with lower access overhead and energy consumption. To stimulate service provisioning by cloudlets and improve resource utilization, a feasible and efficient incentive mechanism is required to charge mobile users and reward cloudlets. Although auction has been considered as a promising form for incentive, it is challenging to design an auction mechanism that holds certain desirable properties for the cloudlet scenario. Truthfulness and system efficiency are two crucial properties in addition to computational efficiency, individual rationality and budget balance. In this paper, we first propose a feasible and truthful incentive mechanism (TIM), to coordinate the resource auction between mobile devices as service users (buyers) and cloudlets as service providers (sellers). Further, TIM is extended to a more efficient design of auction (EDA). TIM guarantees strong truthfulness for both buyers and sellers, while EDA achieves a fairly high system efficiency but only satisfies strong truthfulness for sellers. We also show the difficulties for the buyers to manipulate the resource auction in EDA and the high expected utility with truthful bidding.

We prove that the squared Rényi-α entanglement (SRαE), which is the generalization of entanglement of formation (EOF), obeys a general monogamy inequality in an arbitrary N -qubit mixed state. Furthermore, for a class of Rényi-α entanglement, we prove that the monogamy relations of the SRαE have a hierarchical structure when the N -qubit system is divided into k parties. As a byproduct, the analytical relation between the Rényi-α entanglement and the squared concurrence is derived for bipartite 2 ⊗ d systems. Based on the monogamy properties of SRαE, we can construct the corresponding multipartite entanglement indicators which still work well even when the indicators based on the squared concurrence and EOF lose their efficacy. In addition, the monogamy property of the µ-th power of Rényi-α entanglement is analyzed.

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Abstract-With the interworking between a cellular network and wireless local area networks (WLANs), an essential aspect of resource management is taking advantage of the overlay network structure to efficiently share the multi-service traffic load between the interworked systems. In this study, we propose a new load sharing scheme for voice and elastic data services in a cellular/WLAN integrated network. Admission control and dynamic vertical handoff are applied to pool the free bandwidths of the two systems to effectively serve elastic data traffic and improve the multiplexing gain. To further combat the cell bandwidth limitation, data calls in the cell are served under an efficient service discipline, referred to as shortest remaining processing time (SRPT) [1]. The SRPT can well exploit the heavy-tailedness of data call size to improve the resource utilization. An accurate analytical model is developed to determine an appropriate size threshold so that data calls are properly distributed to the integrated cell and WLAN, taking into account the load conditions and traffic characteristics. It is observed from extensive simulation and numerical analysis that the new scheme significantly improves the overall system performance.Index Terms-Cellular/WLAN interworking, resource management, quality of service, load sharing, vertical handoff, admission control.