  Understanding the fundamental end-to-end delay performance in mobile ad hoc
networks (MANETs) is of great importance for supporting Quality of Service
(QoS) guaranteed applications in such networks. While upper bounds and
approximations for end-to-end delay in MANETs have been developed in
literature, which usually introduce significant errors in delay analysis, the
modeling of exact end-to-end delay in MANETs remains a technical challenge.
This is partially due to the highly dynamical behaviors of MANETs, but also due
to the lack of an efficient theoretical framework to capture such dynamics.
This paper demonstrates the potential application of the powerful
Quasi-Birth-and-Death (QBD) theory in tackling the challenging issue of exact
end-to-end delay modeling in MANETs. We first apply the QBD theory to develop
an efficient theoretical framework for capturing the complex dynamics in
MANETs. We then show that with the help of this framework, closed form models
can be derived for the analysis of exact end-to-end delay and also per node
throughput capacity in MANETs. Simulation and numerical results are further
provided to illustrate the efficiency of these QBD theory-based models as well
as our theoretical findings.
