Traffic modeling in mobile internet protocol : version 6.

Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2005.Mobile Internet Protocol Version 6 (lPv6) is the new version of the Internet Protocol (IP) born out of the great success of Internet Protocol version 4 (IPv4). The motivation behind the development of Mobile IPv6 standard stems from user's demand for mobile devices which can connect and move seamlessly across a growing number of connectivity options. It is both suitable for mobility between subnets across homogenous and inhomogeneous media. The protocol allows a mobile node to communicate with other hosts after changing its point of attachment from one subnet to another. The huge address space available meets the requirements for rapid development of internet as the number of mobile nodes increases tremendously with the rapid expansion of the internet. Mobility, security and quality of service (QoS) being integrated in Mobile TPv6 makes it the important foundation stone for building the mobile information society and the future internet. Convergence between current network technologies: the intern et and mobile telephony is taking place, but the internet's IP routing was designed to work with conventional static nodes. Mobile IPv6 is therefore considered to be one of the key technologies for realizing convergence which enables seamless communication between fixed and mobile access networks. For this reason, there is numerous works in location registrations and mobility management, traffic modeling, QoS, routing procedures etc. To meet the increased demand for mobile telecommunications, traffic modeling is an important step towards understanding and solving performance problems in the future wireless IP networks. Understanding the nature of this traffic, identifying its characteristics and developing appropriate traffic models coupled with appropriate mobility management architectures are of great importance to the traffic engineering and performance evaluation of these networks. It is imperative that the mobility management used keeps providing good performance to mobile users and maintain network load due to signaling and packet delivery as low as possible. To reduce this load, Intemet Engineering Task Force (IETF) proposed a regional mobility management. The load is reduced by allowing local migrations to be handled locally transparent from the Home Agent and the Correspondent Node as the mobile nodes roams freely around the network. This dissertation tackles two major aspects. Firstly, we propose the dynamic regional mobility management (DRMM) architecture with the aim to minimize network load while keeping an optimal number of access routers in the region. The mobility management is dynamic based on the movement and population of the mobile nodes around the network. Most traffic models in telecommunication networks have been based on the exponential Poisson processes. This model unfortunately has been proved to be unsuitable for modeling busty IP traffic. Several approaches to model IP traffic using Markovian processes have been developed using the Batch Markovian Alrival Process (BMAP) by characterizing arrivals as batches of sizes of different distributions. The BMAP is constructed by generalizing batch Poisson processes to allow for non-exponential times between arrivals of batches while maintaining an underlying Markovian structure. The second aspect of this dissertation covers the traffic characterization. We give the analysis of an access router as a single server queue with unlimited waiting space under a non pre-emptive priority queuing discipline. We model the arrival process as a superposition of BMAP processes. We characterize the superimposed arrival processes using the BMAP presentation. We derive the queue length and waiting time for this type of queuing system. Performance of this traffic model is evaluated by obtaining numerical results in terms of queue length and waiting time and its distribution for the high and low priority traffic. We finally present a call admission control scheme that supports QoS

Buffer management and cell switching management in wireless packet communications

The buffer management and the cell switching (e.g., packet handoff) management using buffer management scheme are studied in Wireless Packet Communications. First, a throughput improvement method for multi-class services is proposed in Wireless Packet System. Efficient traffic management schemes should be developed to provide seamless access to the wireless network. Specially, it is proposed to regulate the buffer by the Selective- Delay Push-In (SDPI) scheme, which is applicable to scheduling delay-tolerant non-real time traffic and delay-sensitive real time traffic. Simulation results show that the performance observed by real time traffics are improved as compared to existing buffer priority scheme in term of packet loss probability. Second, the performance of the proposed SDPI scheme is analyzed in a single CBR server. The arrival process is derived from the superposition of two types of traffics, each in turn results from the superposition of homogeneous ON-OFF sources that can be approximated by means of a two-state Markov Modulated Poisson Process (MMPP). The buffer mechanism enables the ATM layer to adapt the quality of the cell transfer to the QoS requirements and to improve the utilization of network resources. This is achieved by selective-delaying and pushing-in cells according to the class they belong to. Analytical expressions for various performance parameters and numerical results are obtained. Simulation results in term of cell loss probability conform with our numerical analysis. Finally, a novel cell-switching scheme based on TDMA protocol is proposed to support QoS guarantee for the downlink. The new packets and handoff packets for each type of traffic are defined and a new cutoff prioritization scheme is devised at the buffer of the base station. A procedure to find the optimal thresholds satisfying the QoS requirements is presented. Using the ON-OFF approximation for aggregate traffic, the packet loss probability and the average packet delay are computed. The performance of the proposed scheme is evaluated by simulation and numerical analysis in terms of packet loss probability and average packet delay

MOBILITY SUPPORT ARCHITECTURES FOR NEXT-GENERATION WIRELESS NETWORKS

With the convergence of the wireless networks and the Internet and the booming demand for multimedia applications, the next-generation (beyond the third generation, or B3G) wireless systems are expected to be all IP-based and provide real-time and non-real-time mobile services anywhere and anytime. Powerful and efficient mobility support is thus the key enabler to fulfil such an attractive vision by supporting various mobility scenarios. This thesis contributes to this interesting while challenging topic. After a literature review on mobility support architectures and protocols, the thesis starts presenting our contributions with a generic multi-layer mobility support framework, which provides a general approach to meet the challenges of handling comprehensive mobility issues. The cross-layer design methodology is introduced to coordinate the protocol layers for optimised system design. Particularly, a flexible and efficient cross-layer signalling scheme is proposed for interlayer interactions. The proposed generic framework is then narrowed down with several fundamental building blocks identified to be focused on as follows. As widely adopted, we assume that the IP-based access networks are organised into administrative domains, which are inter-connected through a global IP-based wired core network. For a mobile user who roams from one domain to another, macro (inter-domain) mobility management should be in place for global location tracking and effective handoff support for both real-time and non-real-lime applications. Mobile IP (MIP) and the Session Initiation Protocol (SIP) are being adopted as the two dominant standard-based macro-mobility architectures, each of which has mobility entities and messages in its own right. The work explores the joint optimisations and interactions of MIP and SIP when utilising the complementary power of both protocols. Two distinctive integrated MIP-SIP architectures are designed and evaluated, compared with their hybrid alternatives and other approaches. The overall analytical and simulation results shown significant performance improvements in terms of cost-efficiency, among other metrics. Subsequently, for the micro (intra-domain) mobility scenario where a mobile user moves across IP subnets within a domain, a micro mobility management architecture is needed to support fast handoffs and constrain signalling messaging loads incurred by intra-domain movements within the domain. The Hierarchical MIPv6 (HMIPv6) and the Fast Handovers for MIPv6 (FMIPv6) protocols are selected to fulfil the design requirements. The work proposes enhancements to these protocols and combines them in an optimised way. resulting in notably improved performances in contrast to a number of alternative approaches

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

Modelling and Analysis of Resource Management Schemes in Wireless Networks. Analytical Models and Performance Evaluation of Handoff Schemes and Resource Re-Allocation in Homogeneous and Heterogeneous Wireless Cellular Networks.

Over recent years, wireless communication systems have been experiencing a dramatic and continuous growth in the number of subscribers, thus placing extra demands on system capacity. At the same time, keeping Quality of Service (QoS) at an acceptable level is a critical concern and a challenge to the wireless network designer. In this sense, performance analysis must be the first step in designing or improving a network. Thus, powerful mathematical tools for analysing most of the performance metrics in the network are required. A good modelling and analysis of the wireless cellular networks will lead to a high level of QoS. In this thesis, different analytical models of various handoff schemes and resource re-allocation in homogeneous and heterogeneous wireless cellular networks are developed and investigated. The sustained increase in users and the request for advanced services are some of the key motivations for considering the designing of Hierarchical Cellular Networks (HCN). In this type of system, calls can be blocked in a microcell flow over to an overlay macrocell. Microcells in the HCN can be replaced by WLANs as this can provide high bandwidth and its users have limited mobility features. Efficient sharing of resources between wireless cellular networks and WLANs will improve the capacity as well as QoS metrics. This thesis first presents an analytical model for priority handoff mechanisms, where new calls and handoff calls are captured by two different traffic arrival processes, respectively. Using this analytical model, the optimised number of channels assigned to II handover calls, with the aim of minimising the drop probability under given network scenarios, has been investigated. Also, an analytical model of a network containing two cells has been developed to measure the different performance parameters for each of the cells in the network, as well as altogether as one network system. Secondly, a new solution is proposed to manage the bandwidth and re-allocate it in a proper way to maintain the QoS for all types of calls. Thirdly, performance models for microcells and macrocells in hierarchical cellular networks have been developed by using a combination of different handoff schemes. Finally, the microcell in HCN is replaced by WLANs and a prioritised vertical handoff scheme in an integrated UMTS/WLAN network has been developed. Simulation experiments have been conducted to validate the accuracy of these analytical models. The models have then been used to investigate the performance of the networks under different scenarios

QoS provisioning and mobility management for IP-based wireless LAN

Today two major technological forces drive the telecommunication era: the wireless cellular systems and the Internet. As these forces converge, the demand for new services, increasing bandwidth and ubiquitous connectivity continuously grows. The next-generation mobile systems will be based solely or in a large extent, on the Internet Protocol (IP). This thesis begins by addressing the problems and challenges faced in a multimedia, IP-based Wireless LAN environment. The ETSI HiperLAN/2 system has been mainly selected as the test wireless network for our theoretical and simulation experiments. Apart from the simulations, measurements have been taken from real life test scenarios, where the IEEE 802.11 system was used (UniS Test-bed). Furthermore, a brief overview of the All-IP network infrastructure is presented. An extension to the conventional wireless (cellular) architecture, which takes advantage of the IP network characteristics, is considered. Some of the trends driving the 3G and WLANs developments are explored, while the provision of quality of service on the latter for real-time and non-real-time multimedia services is investigated, simulated and evaluated. Finally, an efficient and catholic Q0S framework is proposed. At the same time, the multimedia services should be offered in a seamless and uninterrupted manner to users who access the all-IP infrastructure via a WLAN, meeting the demands of both enterprise and public environments anywhere and anytime. Thus providing support for mobile communications not only in terms of terminal mobility, as is currently the case, but also for session, service and personal mobility. Furthermore, this mobility should be available over heterogeneous networks, such as WLANs, IJMTS, as well as fixed networks. Therefore, this work investigates issues such as, multilayer and multi-protocol (SIP-Mobile IP-Cellular IP) mobility management in wireless LAN and 3G domains. Several local and global mobility protocols and architectures have been tested and evaluated and a complete mobility management framework is proposed. Moreover, integration of simple yet efficient authentication, accounting and authorisation mechanisms with the multimedia service architecture is an important issue of IP-based WLANs. Without such integration providers will not have the necessary means to control their provided services and make revenue from the users. The proposed AAA architecture should support a robust AAA infrastructure providing secure, fast and seamless access granting to multimedia services. On the other hand, a user wishing a service from the All-IP WLAN infrastructure needs to be authenticated twice, once to get access to the network and the other one should be granted for the required service. Hence, we provide insights into these issues by simulating and evaluating pre-authentication techniques and other network authentication scenarios based on the wellknown IEEE 802.lx protocol for multimedia IP-based WLANs.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Improved Vertical Handoff Schemes for K-Tier Heterogeneous Wireless Network

The vertical hando_ schemes for heterogeneous wireless networks are presented in the thesis. A heterogeneous network consists of multiple tiers of available wireless net-works, framed as K-tier heterogeneous wireless network (KHWN). A typical KHWN adopted in the thesis consists of Global System for Mobile communication (GSM), Universal Mobile Telecommunications System (UMTS), Wireless Local Area Network (WLAN) and Long Term Evolution (LTE). The hando_ scheme considers the Receiv- ing Signal Strength (RSS)and Signal to Interference and Noise Ratio (SINR) with the tra_c cost as the key parameters for vertical hando_ decision making process. The key parameter RSS is estimated through a proposed path loss model based on local terrain and is observed to be better as compared to the earlier empirical models. With the local terrain input, the path loss model and RSS has been estimated for GSM, UMTS, WLAN and LTE networks. Following this a VHO scheme is proposed for voice and data communication. Subsequently this SINR and a KHWN consisting of multi-tier with the four types of services viz. voice call, video streaming, web brows- ing and telemetry are considered. In this multi-hierarchy decision making process the best suited Analytical and Hierarchical Process (AHP) is applied, for the decision making process in VHO. The proposed scheme of vertical hando_ provides higher QoS than the earlier algorithms of Combined SINR based Vertical Hando_ (CSVH) and Multi-dimensional SINR based vertical hando_ (MSVH). Also the unnecessary VHO are controlled by the proposed scheme. The result shows that the proposed scheme provides low cost tra_c and overall system throughput with a control of unnecessary hando_s for all kinds of services within the KHWN

Satellite Networks: Architectures, Applications, and Technologies

Since global satellite networks are moving to the forefront in enhancing the national and global information infrastructures due to communication satellites' unique networking characteristics, a workshop was organized to assess the progress made to date and chart the future. This workshop provided the forum to assess the current state-of-the-art, identify key issues, and highlight the emerging trends in the next-generation architectures, data protocol development, communication interoperability, and applications. Presentations on overview, state-of-the-art in research, development, deployment and applications and future trends on satellite networks are assembled