Interworking Architectures in Heterogeneous Wireless Networks: An Algorithmic Overview
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paper_title: Seamless integration of mobile WiMAX in 3GPP networks

paper_content:

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/3G 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 broadband 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.
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Title: Interworking Architectures in Heterogeneous Wireless Networks: An Algorithmic Overview

Section 1: INTRODUCTION
Description 1: This section introduces the concept of heterogeneous wireless networks, detailing their purpose, benefits, and the need for efficient interworking among different Radio Access Technologies (RATs).

Section 2: WiMAX and 3GPP
Description 2: This section discusses a framework based on IEEE standards for performing Vertical Handover (VHO) from a 3GPP access network to a WiMAX access network, explaining the entities and protocols involved.

Section 3: Mobile WiMAX (802.16) and WCDMA (3G UMTS)
Description 3: This section describes the interworking of Mobile WiMAX and UTRAN based on the 3GPP EPC, highlighting the nodes, logical interfaces, and procedures crucial for VHO.

Section 4: Algorithm for Overlapping Handover
Description 4: This section outlines the steps involved in the VHO process for overlapping network coverage areas, including key algorithms for dual link layer registration and service registration.

Section 5: Call Flow Algorithm for WiMAX - 3GPP UTRAN Handover
Description 5: This section presents the handover call flow process from WiMAX to 3GPP UTRAN, detailing the steps and communication flow between the networks.

Section 6: Call Flow Algorithm for 3GPP UTRAN - WIMAX Handover
Description 6: This section covers the reverse handover call flow process from 3GPP UTRAN to WiMAX, describing the procedure and requirements for seamless transition.

Section 7: SUMMARY
Description 7: This section summarizes the benefits and implications of interworking RATs, emphasizing the importance of inter-technology mobility for operators and the seamless integration of communication networks.
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