Telecommunications Networks and Services Group
The Telecommunication Networks and Services (TNS) Group’s mission is to contribute to the development of present and future wireless data systems through research activities focused on network architecture and protocol issues in the provision of communication services over wireless networks.
Overview
|
The Telecommunications Networks and Services Group (TNS) undertakes research and development in the following areas:
|
Group LeaderProject examples
Data transport performance in multi-hop environment
In infrastructure-less networks, wireless nodes often communicate over distances exceeding many times the effective transmission range. Paths from source to destination may involve multiple radio hops, resulting in severe limitations on data transport performance, e.g., throughput. Thorough knowledge of the mechanisms determining performance limits in such environment, and the ability to turn this knowledge into guidelines for network and protocol engineering, are a critical component of being able to apply the infrastructure-less networking paradigm to the development of rapidly deployable military and emergency response data networks, residential access wireless mesh networks, ad-hoc extensions to 3G/Next Generation Network infrastructure, and sensor networks.
Highlights of research in this area include results on optimum TCP window size for multi-hop paths and throughput gain achievable with simultaneous transport over multiple paths, accurate analytical model of 802.11 node throughput for a wide range of load conditions, and a non-invasive local method for real-time estimation of throughput available at 802.11 node in a multi-hop network. Resulting from these was a proof-of-concept design of a high performance rate-based ad-hoc transport protocol. Simulation results demonstrated that this protocol greatly outperformed other known ad-hoc transport protocols in terms of throughput-delay performance and timeliness/stability of flow control. Other research in this area included work on CDMA based medium access control protocol for ad-hoc networks, complete with an effective power control method, cross-layer optimisation of transport performance based on predictions of channel state (e.g. fading), and rate balancing at relay nodes in a multi-hop wireless network leading to better transport efficiency.
Routing in dynamic networks
In this topic area, highlights include work on unified(independent of mobility models) metrics of network dynamics developed to investigate the limits on the performance and the cost of routing as functions of network dynamics, group theory based addressing and routing scheme designed for very low computational complexity addressing and routing in sensor networks, and analytical method for calculation of data flows in multiple source/multiple sink sensor networks to enable optimisation of battery usage.
Secure minimum-configuration operation of ad-hoc networks
One of the greatest obstacles in practical deployments of ad-hoc networks is the lack of effective methods for automatic initial configuration of network nodes required to support secure access to network and application services, as well as to resources available in the network. To address this issue, research was initiated on topics such as Public Key based ad-hoc network security solution for key distribution during network start-up and reconfiguration phases, and mobile agent based intrusion detection systems suitable for ad-hoc networks.
Potential applications of this research include security in emergency services networks, secure service discovery and access control for dynamically changing groups of ad-hoc network users, secure personal and vehicular area networking, and secure home networking (SOHO, home infrastructure and appliance control).
Mobile Internet
In applications such as New Generation Networks (4G) roaming in heterogeneous access environment, or enterprise, tactical and emergency response networks with wide-area roaming, one of the most important challenges is to be able to seamlessly handle IP mobility of nodes across administrative domains and disparate access technologies. The requirement of seamless IP mobility means that the handover procedures need to be optimised for minimum latency and data loss, and the reestablishment of services at a new point of attachment has to immediately follow the handover. In 2005, our previous work on adaptive optimisation of IP mobility handovers was extended by work that offers novel solutions for fast context reestablishment in Mobile Internet. The work involved characterisation and classification of context in IP mobility environment, and a thorough study of methods for proactive transfer of context, based on the concept of forced (proactive) handover.
Satellite Networking
The TNS Group is one of few groups that has maintained currency of expertise in network architecture and protocol engineering for satellite communications. Recently a study was carried out on MPLS transport, dynamic routing and QoS control in IPv6 based LEO satellite network, complete with a system-level design of the network architecture. Also a study was carried out on value-based scheduling of information broadcasts in a military satellite broadcast system.
Connecting ad-hoc network islands to the Internet
Most practical applications of ad-hoc (infrastructure-less) networking require that the ad-hoc network is connected to the Internet. These applications may include remote access to vehicular and home networks, remote access to sensor networks (e.g. in tele-health and remote monitoring), and wide area connectivity for rapidly-deployable military and emergency services networks. Inmost cases, connectivity to the Internet is achieved thanks to user nodes connected to the Internet that make the connectivity available to others (these user nodes become interconnection gateways).Research in this area resulted in development and evaluation of solutions to gateway discovery and selection, to a number of issues in handling IP mobility in a multi-hop ad-hoc environment, and to routing across the boundary between ad-hoc and Internet domains.
Contact
| Associate Professor Arek Dadej Associate Research Professor |
|
| Arek.Dadej@unisa.edu.au | |
| Phone | +61 8 830 23304 (office) |
| Fax | +61 8 830 23873 |
| Location | Room 2-6 SPRI Building Mawson Lakes Campus, UniSA |
| Post | Institute for Telecommunications Research Mawson Lakes Boulevard Mawson Lakes SA 5095 Australia |