Mobile communications are becoming an increasingly important aspect of everyday life -from the ubiquitous cellular telephone with text messaging services to advanced video conferencing and mobile Internet access. One of my main research interests is to investigate and provide a level of support for multimedia applications and services for future mobile networks. I currently pursue this research as part of the Mobile-IPv6 Systems Research Lab (MSRL) project.

The next generation Internet protocol, IPv6, together with the IETF proposed standard for host mobility, Mobile IPv6, promises to provide many beneficial mechanisms to solve this problem. The focus of my research is to investigate how effective these mechanisms are for mobile applications when applied in real-life networks, and address any problems discovered through that investigation. This work builds on previous expertise gained as part of the LandMARC project, where I was involved in the development of Mobile IPv6 implementations for Windows 2000, XP and .NET Server as well as Windows CE 4.x.

My research interests in this context are:

• Wireless Overlay Networks

• Horizontal and Vertical Handoffs

• Fast Network Handoffs

• Support for real-time Multimedia Streaming (e.g. VoIP)

• WWAN-WLAN Interworking

• IPv4/IPv6 Transitioning

• Security, Access Control and Accounting
  

Programmable Networks

The distinction between programming paradigms of network devices and end systems has led to a growing gap between the capabilities of end nodes and intermediate devices. While, for example, programmable end systems have included sophisticated support for multimedia streaming for many years, multimedia support for network devices is still in the process of standardization, and deployment is held back by the problems of upgrading significant amounts of network hardware and software.

As part of the LandMARC project, I designed and developed a novel programmable router for on-demand deployment of new and enhanced network services, called LARA++. This second-generation Lancaster Active Router Architecture (LARA++) provides a programmable platform for active services based on the composition of many small software components. These so called "active components" are dynamically loadable onto LARA++ active routers where they provide additional or extended services for individual data streams or whole protocol families. LARA++ is advantageous over conventional implementations in terms of reusability of active code and customisability of user tailored services, as it allows individual software components to be upgraded more easily and new components to be added gradually.

This conceptual work as well as the implementation of a proof-of-concept LARA++ router has become a substantial element of my Ph.D. research, which I have completed in November 2002. Further work on LARA++ is currently carried out as part of the EPSRC-funded ProgNet project. The goal of this project is to complete a full-strength LARA++ implementation and use it to provide active services for mobile and nomadic users. The LARA++ routers sitting on the edge of the fix network (in this context) can be dynamically programmed to improve mobile communications and network services for users roaming between different networks.

I am also interested in exploring active services and components that assist mobile nodes in ad-hoc environments. Since the LARA++ architecture allows dynamic programmability and extensibility of device functionality, it provides an ideal platform for ad-hoc negotiation and deployment of communication protocols. As a consequence, the aim is to define the necessary LARA++ functionality and implement this subset of the architecture on ad-hoc client devices.

Further research interests in the context of Programmable Networks are:

• Modular Active Node Architectures

• Node-local Service Composition Mechanisms

• Network-wide Service Composition and Deployment

• Active Services to support:
     - Mobile Environments (Fast Handoff Support, Nomadic Support, etc.)
     - Security (Authentication and Access Control)
     - Ad-hoc Environments
     - Protocol Transitioning (IPv4/v6)
     - Network Quality-of-Service

• Security Aspects of Programmable Networks

• Network Processors

Other Areas of Interest

• Ad-hoc Networking

• Security (Privacy, Confidentiality, Access Control)

• Quality-of-Service Mechanism
     - Integrated Services (IntServ) and Resource Reservation Mechanisms
     - Differentiated Services (DiffServ)

• Peer-to-Peer Networks

• Overlay Networks