To be able to satisfy their users, interactive applications like video conferences require a certain Quality-of-Service from heterogeneous networks. This paper proposes the use of throughput histograms as Quality-of-Service indicator. These histograms are built from local, unsynchronized, passive measurements of packet streams from the viewpoint of an application. They can easily be exchanged between sender and receiver, and their comparison provides information about severity and type of a potential bottleneck. We demonstrate the usefulness of these indicators for evaluating the transport quality perceived by a video conferencing application and its users in the presence of a bottleneck.
En flaskhalsindikator som bygger på att ta differensen på hastighets-/genomströmningshistogram efter och framför en flaskhals introduceras. Den tillämpas på en videokonferens som störs på kontrollerat sätt av annan trafik. Nyckelord: Internet, flaskhals, flödesmodell, hastighetsstatistik