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To support fast and efficient handovers in mobile WIMAX, we propose Fast Intra-Network and Cross-layer Handover (FINCH) for intradomain (intra-CSN) mobility management. FINCH is a complementary protocol to Mobile IP (MIP), which deals with interdomain (inter-CSN) mobility management in mobile WiMAX. FINCH can reduce not only the handover latency but also the end-to- end latency for MIP. Paging extension for FINCH is also proposed to enhance the energy efficiency. The proposed FINCH is especially suitable for real-time services in frequent handover environment, which is important for future mobile WiMAX networks. In addition, FINCH is a generic protocol for other IEEE 802-series standards. This is especially beneficial for the integration of heterogeneous networks, for instance, the integration of WiMAX and WiFi networks. Both mathematical analysis and simulation are developed to analyze and compare the performance of FINCH with other protocols. The results show that FINCH can support fast and efficient link layer and intradomain handovers. The numerical results can also be used to select proper network configurations. [ABSTRACT FROM AUTHOR]

The IEEE 802.16 Standard defines the mesh mode for media access control for external and internal packet transmission. In the IEEE 802.16 mesh mode, the allocation of minislots is handled by centralized scheduling and distributed scheduling, which are independently exercised. This paper proposes the Combined Distributed and Centralized (CDC) and Combined Distributed and Centralized with Queue capability (CDCQ) schemes to combine distributed scheduling and centralized scheduling so that the minislot allocation can be more flexible and the utilization is increased. Two scheduling algorithms, i.e., the Round-Robin (RR) and Greedy algorithms, are used as the baseline algorithms for centralized scheduling. This paper pro- poses an analytical model and conducts simulation experiments to investigate the performance of the CDC-series schemes with the RR and Greedy algorithms in terms of the acceptance rate of both external and internal packet data. Our study indicates that the CDC-series schemes outperform the scheme proposed in the IEEE standard. [ABSTRACT FROM AUTHOR]

Ethernet services represent a steadily growing portion of the fixed telecommunication market. To enable the provisioning of Ethernet services over IEEE 802.16e, the Mobile WiMAX network artchitecture supports transparent Ethernet transport as an optional extension to the IP services architecture. Ethernet support is tightly aligned to the IP services network model, and leverages many data path and control plane functions from its IP sibling to keep the implementation and operation overhead low for the Ethernet extension. Mobile WiMAX provides IP services as well as Ethernet services over the same mobile access network. The intrinsic mobility support may create new deployment opportunities for Ethernet services. Initially, the Ethernet extension may be mostly used to realize wireless access for DSL networks based on the same network interfaces defined for the wired Ethernet-based DSL aggregation. [ABSTRACT FROM AUTHOR]

As the wireless industry makes its way to the next generation of mobile systems, it is important to engineer solutions that enable seamless integration of emerging 4G access technologies within the currently deployed and/or evolved 2G/30 infrastructures. In this article we address a specific case of such a seamless integration, that of mobile WiMAX in evolved 3GPP networks. In this context we investigate the architecture and the key procedures that enable this integration, and we also introduce a novel handover mechanism that enables seamless mobility between mobile WiMAX and legacy 3GPP access, such as UTRAN or GERAN. The core characteristic of this novel handover mechanism is that mobile terminals do not need to support simultaneous transmission on both WiMAX and 3GPP accesses; therefore, it mitigates the RF coexistence issues that exist otherwise and improves handover performance. In addition, we provide a brief overview of mobile WiMAX and the evolved 3GPP network technologies, and we set the appropriate background material before presenting our proposed handover mechanism. Our main conclusion is that integrating mobile WiMAX in evolved 3GPP networks is a compelling approach for providing wireless broad- band services, and mobility across WiMAX and 3GPP access can become seamless and efficient with no need for mobile terminals to support simultaneous transmission on both types of access. [ABSTRACT FROM AUTHOR]

Femtocells are viewed as a promising option for mobile operators to improve coverage and provide high-data-rate services in a cost-effective manner. The idea is to overlay low-power and low-cost base station devices, Femto-APs, on the existing cellular network, where each Femto-AP provides high-speed wireless connection to subscribers within a small range. In particular, Femto-APs can be used to serve indoor users, resulting in a powerful solution for ubiquitous indoor and outdoor coverage, using a single access technology such as WiMAX. In this article we consider a WiMAX network deploying both macro BSs and Femto-APs, where it is assumed that Femto-APs have wired backhaul such as cable or DSL and operate on the same frequency band as macro BSs. Simulation results show that significant areal capacity (throughput per unit area) gain can be achieved via intense spatial reuse of the wireless spectrum. In addition, Femto-APs improve indoor coverage, where the macro BS signal may be weak. Motivated by the gains in capacity and coverage offered by femtocells, we review the state of the art of this "infant" technology, including use cases and network deployment scenarios, technical challenges that need to be addressed, and current standardization and industry activity. [ABSTRACT FROM AUTHOR]

Mobile WiMAX was successfully adopted by ITU as one of the IMT-2000 technologies in November 2007. Since then mobile WiMAX (a.k.a. IP-OFDMA) has officially become a major global cellular wireless standard along with 3GPP UMTS/HSPA and 3GPP2 CDMA/EVDO. Mobile WiMAX is an OFDM-based technology available for deployment today, and new WIMAX devices come to market at much reduced cost than that of current 3G solutions. Currently over 260 service providers are deploying fixed, portable and mobile WiMAX networks in 110 countries. This article provides an overview of the mobile WiMAX system and its performance under various configurations, channel conditions, and types of data traffic. Furthermore, the article provides an overview of mobile WiMAX evolution. [ABSTRACT FROM AUTHOR]