Routingalgorithmen für infrastrukturlose Paketfunknetze mit kooperativen mobilen Stationen

This dissertatiom introduces some improvements in ad hoc network routing. This kind of networking does not require any kind of infrastructure, all participating hosts have to cooperate to build up a self organizing communication network. Host mobility and error-prone wireless links require special routing algorithms for this environment.
The dissertation starts with an introduction to standard routing algorithms and continues with a description and a classification of existing ad hoc routing algorithms. After that, a new algorithm called the “Tree Exchange Routing Algorithm (TERA)” is presented, which offers a highly efficient path calculation method. A further improvement in bandwidth efficiency is achieved by extending TERA with restricted route optimization. This extension limits new route calculations to major topology changes of the network. Simulations show that these improvments allow a reduction of routing messages up to 50 %.
An additional chapter explains the implementation of load distribution in TERA to reduce the network load of single hosts by randomizing the data flow. After that, some advanced methods for connecting ad hoc networks to the internet are described. This includes a discussion of security problems and a description of necessary protocol adaptations to enable interaction between ad hoc and internet routing.