A Survey on Handover Management in Mobility Architectures

This work presents a comprehensive and structured taxonomy of available techniques for managing the handover process in mobility architectures. Representative works from the existing literature have been divided into appropriate categories, based on their ability to support horizontal handovers, vertical handovers and multihoming. We describe approaches designed to work on the current Internet (i.e. IPv4-based networks), as well as those that have been devised for the "future" Internet (e.g. IPv6-based networks and extensions). Quantitative measures and qualitative indicators are also presented and used to evaluate and compare the examined approaches. This critical review provides some valuable guidelines and suggestions for designing and developing mobility architectures, including some practical expedients (e.g. those required in the current Internet environment), aimed to cope with the presence of NAT/firewalls and to provide support to legacy systems and several communication protocols working at the application layer

Multimedia session continuity in the IP multimedia subsystem : investigation and testbed implementation

Includes bibliographical references (leaves 91-94).The advent of Internet Protocol (IP) based rich multimedia services and applications has seen rapid growth and adoption in recent years, with an equally increasing user base. Voice over IP (VoIP) and IP Television (IPTV) are key examples of services that are blurring the lines between traditional stove-pipe approach network infrastructures. In these, each service required a different network technology to be provisioned, and could only be accessed through a specific end user equipment (UE) technology. The move towards an all-IP core network infrastructure and the proliferation of multi-capability multi-interface user devices has spurred a convergence trend characterized by access to services and applications through any network, any device and anywhere

A Unified Mobility Management Architecture for Interworked Heterogeneous Mobile Networks

The buzzword of this decade has been convergence: the convergence of telecommunications, Internet, entertainment, and information technologies for the seamless provisioning of multimedia services across different network types. Thus the future Next Generation Mobile Network (NGMN) can be envisioned as a group of co-existing heterogeneous mobile data networking technologies sharing a common Internet Protocol (IP) based backbone. In such all-IP based heterogeneous networking environments, ongoing sessions from roaming users are subjected to frequent vertical handoffs across network boundaries. Therefore, ensuring uninterrupted service continuity during session handoffs requires successful mobility and session management mechanisms to be implemented in these participating access networks. Therefore, it is essential for a common interworking framework to be in place for ensuring seamless service continuity over dissimilar networks to enable a potential user to freely roam from one network to another. For the best of our knowledge, the need for a suitable unified mobility and session management framework for the NGMN has not been successfully addressed as yet. This can be seen as the primary motivation of this research. Therefore, the key objectives of this thesis can be stated as: To propose a mobility-aware novel architecture for interworking between heterogeneous mobile data networks To propose a framework for facilitating unified real-time session management (inclusive of session establishment and seamless session handoff) across these different networks. In order to achieve the above goals, an interworking architecture is designed by incorporating the IP Multimedia Subsystem (IMS) as the coupling mediator between dissipate mobile data networking technologies. Subsequently, two different mobility management frameworks are proposed and implemented over the initial interworking architectural design. The first mobility management framework is fully handled by the IMS at the Application Layer. This framework is primarily dependant on the IMS’s default session management protocol, which is the Session Initiation Protocol (SIP). The second framework is a combined method based on SIP and the Mobile IP (MIP) protocols, which is essentially operated at the Network Layer. An analytical model is derived for evaluating the proposed scheme for analyzing the network Quality of Service (QoS) metrics and measures involved in session mobility management for the proposed mobility management frameworks. More precisely, these analyzed QoS metrics include vertical handoff delay, transient packet loss, jitter, and signaling overhead/cost. The results of the QoS analysis indicates that a MIP-SIP based mobility management framework performs better than its predecessor, the Pure-SIP based mobility management method. Also, the analysis results indicate that the QoS performances for the investigated parameters are within acceptable levels for real-time VoIP conversations. An OPNET based simulation platform is also used for modeling the proposed mobility management frameworks. All simulated scenarios prove to be capable of performing successful VoIP session handoffs between dissimilar networks whilst maintaining acceptable QoS levels. Lastly, based on the findings, the contributions made by this thesis can be summarized as: The development of a novel framework for interworked heterogeneous mobile data networks in a NGMN environment. The final design conveniently enables 3G cellular technologies (such as the Universal Mobile Telecommunications Systems (UMTS) or Code Division Multiple Access 2000 (CDMA2000) type systems), Wireless Local Area Networking (WLAN) technologies, and Wireless Metropolitan Area Networking (WMAN) technologies (e.g., Broadband Wireless Access (BWA) systems such as WiMAX) to interwork under a common signaling platform. The introduction of a novel unified/centralized mobility and session management platform by exploiting the IMS as a universal coupling mediator for real-time session negotiation and management. This enables a roaming user to seamlessly handoff sessions between different heterogeneous networks. As secondary outcomes of this thesis, an analytical framework and an OPNET simulation framework are developed for analyzing vertical handoff performance. This OPNET simulation platform is suitable for commercial use

Interworking between WLAN and 3G Cellular Networks: An IMS Based Architecture

In this paper, a novel architecture for interworking of the Wireless Local Area Network (WLAN) and the Third Generation (3G) mobile cellular network is presented. This architecture is a hybrid model with additional controls compared with the existing architectures and the use of IP Multimedia Subsystem (IMS), as an arbitrator for coupling and real-time session management. Furthermore, a new networking entity called a mobility manager has been introduced within the IMS for seamless management of vertical handoffs. Efficient strategies for IP address distribution and bypassing high traffic loads form the cellular core network are other benefits of this architecture

Multicast Mobility in Mobile IP Version 6 (MIPv6) : Problem Statement and Brief Survey

Publisher PD

Transparent network-assisted flow mobility for multimedia applications in IMS environments

Cellular network operators are striving to solve the problem caused by the increasing volume of traffic over their networks. Given the proliferation of multi-interface devices, offloading part of the traffic to available access networks (e. g., WiFi or 3G access networks, even from other operators) seems to be a promising alternative. Here, we propose an IMS-compatible solution for flow mobility between access networks that exhibits two key features: flow mobility is transparent to both local applications at mobile nodes and their communication peers (e. g., multimedia content servers), and mobility operations are assisted by the network, so the home network supports the terminal in the process of access network discovery, and provides the terminal with policies that meet visited and home operators' roaming agreements while optimizing the use of their networks. The proposed solution has been validated using a real IMS testbed with Ethernet and WiFi access networks, where the mobility of UDP and TCP flows has been tested.The work in this article has been partially granted by the Madrid Community through the MEDIANET project (S-2009/TIC-1468) and by the Celtic UP-TO-US project (TSI-020400-2010-114)Publicad

Supervisor virtual machine for VoLTE service on a cloud environment

With the continuing growth of Voice of Long Term Evolution (VoLTE) networks, coupled with the need of Mobile Operators to reduce maintenance costs, Cloud Service deployment is becoming a common application. This study was designed to create a method capable of improving the Operations and Monitoring activities of a VoLTE service that is deployed on a Cloud platform. In this study, we present contents referring to the constituent elements of a VoLTE network, and we review in detail the features of the Telephony Application Server. For this study, TAS used was the Open TAS. Also included in this study is a generic explanation of Cloud Openstack’s behavior. The presented method implies the creation of a virtual machine Supervisor and its deployment in Cloud. This virtual machine is capable of establishing SSH connections with open TAS to extract the Clear Codes report, which identifies the state with which calls were terminated for analysis. The virtual machine contains defined limits, which check if they have been exceeded. If this a limit is excited, the virtual machine notifies the system operator of an incident. This study presents the possibilities of implementation in a Cloud environment, to improve and automate Operations and Maintenance functions in the Telecommunications network.Com o crescimento contínuo das redes de Voice over Long Term Evolution (VoLTE), juntamente com a necessidade de redução de custo de manutenção pelos Operadores Móveis, a implementação do Serviço em Cloud começa a ser uma aplicação comum. Este estudo foi elaborado com o intuito de criar um método capaz de melhorar as atividades de Operações e Monitorização de um serviço de VoLTE, que esteja implementado numa plataforma Cloud. Neste estudo, encontram-se presentes conteúdos referentes aos elementos constituintes de uma rede de VoLTE, e é revisto em detalhe as funcionalidades do Telephony Application Server. Para este estudo, o TAS utilizado foi o open TAS. Neste estudo, igualmente é incluído uma explicação genérica do comportamento da Cloud Openstack. O método apresentado implica criação de uma máquina virtual Supervisor e da sua implementação na Cloud. Esta máquina virtual é capaz de estabelecer ligações SSH com o open TAS, de modo a extrair o relatório de Clear Codes, que identifica o estado com que as chamadas foram finalizadas, para proceder a análises. A máquina virtual contém limites definidos, os quais verifica se foram excedidos. Caso este evento seja verificado, notificam o operador do sistema para um incidente. Esta é uma proposta que apresenta as possibilidades de implementação num ambiente de Cloud, em melhorar e automatizar as funções de Operações e Manutenção na rede de Telecomunicações