A Dependency-Aware QoS System for Mobile Satellite Communication
Dipl.-Inf. Markus Brückner
Dipl.-Inf. Philipp Drieß
M.Sc. Manuel Osdoba
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
- Deploying reservation-based Quality-of-Service systems in variable environments
like mobile satellite communication requires networks to actively adjust the
status of reservations such that they fit the currently available capacity.
Communication in such a system normally consists of multiple interdependent reservations. Even something as
simple as a single file download via TCP already requires two paths: a broad
downlink (data) and a narrower uplink (acknowledgments). Neither of these works without the other.
A smart QoS system takes these dependencies into account when allocating resources.
In this paper we show that if reservations are handled independently from each other,
capacity may be allocated to paths applications cannot use due to the inherent structure
of the protocols used. We present a system to model relations, enabling
the network to intelligently adapt a set of reservations to a change in transmission
We analyze two communication scenarios and compare how relation-aware and non-aware
fitting algorithms react on a decrease in the link capacity. We show that our
relation-aware design is able to improve on wasted resources and decrease broken sessions.