Introduction

Ad hoc networks will be an important part of our vision of the 4G Telephony environment. Ad hoc networks should be able to robustly adapt to changing network conditions and topologies, having the capability to grow, fragment and reorganise in the absence of centralised, hierarchial infrastructures.
They have many civilian and military uses, whether in infrastructureless environments or as means to extend the boundaries of traditional networks.


Current Work

As part of our ongoing research into ad hoc networking we have implemented some protocols proposed by the ad hoc networking community.
These protocols have been implemented on both the Win32 and WinCE platforms, allowing us to evaluate ad hoc systems on desktop PCs, laptops and PDAs.
At the physical communications level we use a combination of 802.11 wireless ethernet cards, 433MHz radios and IrDA.

WinCE PDAs running the NTRG Stack, using both Wireless Ethernet cards and 433MHz radios.    Schematic of sample test network comprising of laptops and PDAs

Dynamic Source Routing - DSR

  • It is a reactive ad hoc networking protocol currently under consideration by MANET.
  • Our implementation broadly conforms to the DSR MANET draft of March, 2001.
  • It also includes modifications which we determined necessary during the process of implemenation and evaluation.
  • Many DSR links and papers may be found at the CMU site.
  • Optimised Link State Routing - OLSR

  • This is a proactive ad hoc networking protocol also currently under consideration by MANET.
  • Again, our implementation conforms to the OLSR MANET draft of March, 2001.
  • Multipoint Relaying: An Efficient Technique for Flooding in Mobile Wireless Networks describes the main optimisation techniques employed by OLSR.
  • A Zone Routing Protocol hybridising mechanism has also been put in place allowing us to leverage optimal performance from both routing protocols.


    Future Work

  • Design, implementation and evaluation of improved ad hoc network protocols.
  • Development of a dynamic architecture enabling real-time re-configuration of the ad hoc networking systems.