Exploring efficient imperative handover mechanisms for heterogeneous wireless networks

The Next Generation Internet will provide ubiquitous computing by the seamless operation of heterogeneous wireless networks. It will also provide support for quality-ofservice, QoS, fostering new classes of applications and will havea built-in multi-level security environment. A key requirement of this new infrastructure will be support for efficient vertical handover. Y-Comm is a new architecture that will meet the challenge of this new environment. This paper explores the design of efficient imperative handover mechanisms using the Y-Comm Framework. It first looks at different types of handovers, then examines the Y-Comm Framework and shows how Y-Comm maps unto current mobile infrastructure. It then explores support for different handover mechanisms using Y-Comm. Finally, it highlights the development of a new testbed to further investigate the proposed mechanisms

Information for handover management in heterogeneous networks: data representation,languages and integrated platforms

Due to the convergence of radio, television, telephony and Internet areas, the mobility of users, the ubiquity of services, and the development of new technologies to unify access provision, the interaction between providers and users will be required for access on demand in heterogeneous environments. This interaction should allow, in addition to seamless handovers, the negotiation based on technical requirements and user's desires during handover decision processes. The central part of the information being exchanged between the access provider's attachment points and user's devices should be a uniform and common structure that models the handover management information, in terms of what the information represents their semantic meanings and relationships. This work presents a set of ontologies, for this purpose, employed during handover decision processes, in integrated networking platforms for access on demand. A case study is presented, which demonstrates how a service could be integrated in two different platforms for such environment

Exploring multi-homing issues in heterogeneous networks

Mobile devices with two network interfaces (WiFi and 3G) are already commercially available. Pointto- point communications such as Infrared and Bluetooth are also readily used. In the near future, mobile phones will have several interfaces including satellite and new technologies such as Ultrawideband. Hence we must assume that such devices will be multi-homed by default. For various reasons, including network congestion, network resilience and increased endpoint bandwidth, there have been several attempts to address multi-homing. Heterogeneous environments with the need to support vertical handover introduce another set of issues which make the need to solve multi-homing problems more urgent. This paper outlines the issues, looks at past efforts and proposes a solution based on the Location Id/Node Id concept but also argues that additional support is needed to make such an approach efficient for heterogeneous environments

Developing an implementation framework for the future internet using the Y-Comm architecture, SDN and NFV

The Future Internet will provide seamless connectivity via heterogeneous networks. The Y-Comm Architecture is a reference model that has been developed to build future mobile systems for heterogeneous environments. However, the emergence of Software Defined Networking and Network Functional Virtualization will allow the implementation of advanced mobile architectures such as Y-Comm to be prototyped and explored in more detail. This paper proposes an implementation model for the Y-Comm architecture based on these mechanisms. A key component is the design of the Core Endpoint which connects various peripheral wireless networks to the core network. This paper also proposes the development of a Network Management Control Protocol which allows the management routines running in the Cloud to control the underlying networking infrastructure. The system being proposed is flexible and modular and will allow current and future wireless technologies to be seamlessly integrated into the overall system

Exploiting user contention to optimize proactive resource allocation in future networks

In order to provide ubiquitous communication, seamless connectivity is now required in all environments including highly mobile networks. By using vertical handover techniques it is possible to provide uninterrupted communication as connections are dynamically switched between wireless networks as users move around. However, in a highly mobile environment, traditional reactive approaches to handover are inadequate. Therefore, proactive handover techniques, in which mobile nodes attempt to determine the best time and place to handover to local networks, are actively being investigated in the context of next generation mobile networks. The Y-Comm Framework which looks at proactive handover techniques has de�fined two key parameters: Time Before Handover and the Network Dwell Time, for any given network topology. Using this approach, it is possible to enhance resource management in common networks using probabilistic mechanisms because it is now possible to express contention for resources in terms of: No Contention, Partial Contention and Full Contention. As network resources are shared between many users, resource management must be a key part of any communication system as it is needed to provide seamless communication and to ensure that applications and servers receive their required Quality-of-Service. In this thesis, the contention for channel resources being allocated to mobile nodes is analysed. The work presents a new methodology to support proactive resource allocation for emerging future networks such as Vehicular Ad-Hoc Networks (VANETs) by allowing us to calculate the probability of contention based on user demand of network resources. These results are veri�ed using simulation. In addition, this proactive approach is further enhanced by the use of a contention queue to detect contention between incoming requests and those waiting for service. This thesis also presents a new methodology to support proactive resource allocation for future networks such as Vehicular Ad-Hoc Networks. The proposed approach has been applied to a vehicular testbed and results are presented that show that this approach can improve overall network performance in mobile heterogeneous environments. The results show that the analysis of user contention does provide a proactive mechanism to improve the performance of resource allocation in mobile networks

Providing security in 4G systems: unveiling the challenges

Several research groups are working on designing new security architectures for 4G networks such as Hokey and Y-Comm. Since designing an efficient security module requires a clear identification of potential threats, this paper attempts to outline the security challenges in 4G networks. A good way to achieve this is by investigating the possibility of extending current security mechanisms to 4G networks. Therefore, this paper uses the X.805 standard to investigate the possibility of implementing the 3G’s Authentication and Key Agreement (AKA) protocol in a 4G communication framework such as YComm. The results show that due to the fact that 4G is an open, heterogeneous and IP-based environment, it will suffer from new security threats as well as inherent ones. In order to address these threats without affecting 4G dynamics, Y-Comm proposes an integrated security module to protect data and security models to target security on different entities and hence protecting not only the data but, also resources, servers and users

Developing an implementation framework for the future internet using the Y-Comm architecture, SDN and NFV

The Future Internet will provide seamless connectivity via heterogeneous networks. The Y-Comm Architecture is a reference model that has been developed to build future mobile systems for heterogeneous environments. However, the emergence of Software Defined Networking and Network Functional Virtualization will allow the implementation of advanced mobile architectures such as Y-Comm to be prototyped and explored in more detail. This paper proposes an implementation model for the Y-Comm architecture based on these mechanisms. A key component is the design of the Core Endpoint which connects various peripheral wireless networks to the core network. This paper also proposes the development of a Network Management Control Protocol which allows the management routines running in the Cloud to control the underlying networking infrastructure. The system being proposed is flexible and modular and will allow current and future wireless technologies to be seamlessly integrated into the overall system

Exploring intelligent service migration in a highly mobile network

Mobile services allow services to be migrated or replicated closer to users as they move around. This is now regarded as a viable mechanism to provide good Quality of Service to users in highly mobile environments such as vehicular networks. The vehicular environment is rapidly becoming a significant part of the internet and this presents various challenges that must be addressed; this is due to continuous handovers as mobile devices change their point of attachment to these networks resulting in a loss of service. Therefore, this explains the need to build a framework for intelligent service migration. This thesis addresses these issues. It starts by discussing the requirements for intelligent service migration. Then it investigates a low latency Quality of Service Aware Framework as well as an experimental transport protocol that would be favoured by vehicular networks. Furthermore, two analytical models are developed using the Zero-Server Markov Chain technique which is a way of analysing scenarios when the server is not continuously available to serve. Using the Zero-Server Markov Chain, the first analytical model looks at lost service due to continuous handovers and the communication dynamics of vehicular networks, while the second model analyses how service migration affects service delivery in these networks. Formulas are developed to yield the average number of packets in the system, the response time, the probability of blocking and a new parameter called the probability of lost service. These formulas are then applied to the Middlesex VANET Testbed to look at reactive and proactive service migration. These techniques are then incorporated into a new Service Management Framework to provide sustainable Quality of Service and Quality of Experience to mobile users in vehicular networks. This thesis also shows that this new approach is better than current approaches as it addresses key issues in intelligent service migration in such environments, and hence can play a significant part in the development of Intelligent Transport Systems for Smart Cities

Exploiting resource contention in highly mobile environments and its application to vehicular ad-hoc networks

As network resources are shared between many users, resource management must be a key part of any communication system as it is needed to provide seamless communication and to ensure that applications and servers receive their required Quality-of-Service. However, mobile environments also need to consider handover issues. Furthermore, in a highly mobile environment, traditional reactive approaches to handover are inadequate and thus proactive techniques have been investigated. Recent research in proactive handover techniques, defined two key parameters: Time Before Handover and Network Dwell Time for a mobile node in any given networking topology. Using this approach, it is possible to enhance resource management in common networks using probabilistic mechanisms because it is possible to express contention for resources in terms of: No Contention, Partial Contention and Full Contention. This proactive approach is further enhanced by the use of a contention queue to detect contention between incoming requests and those waiting for service. This paper therefore presents a new methodology to support proactive resource allocation for future networks such as Vehicular Ad-Hoc Networks. The proposed approach has been applied to a vehicular testbed and results are presented that show that this approach can improve overall network performance in mobile heterogeneous environments