OSS and QoS management on satellite links

Abstract

First, a business framework for operational support systems (OSS) in communications networks is defined, in the particular case where a satellite link is present. It is shown that the constraints added by the satellite link are the need to minimise management traffic while at the same time policing QoS parameters such as delay and delay variation. Secondly, the use of trace packets is used to estimate end-to-end QoS parameters of delay and delay variation. It is shown that the use of trace packets has advantages in terms of management traffic when the satellite link (or any network link) becomes congested. Contrary to intuition, the accuracy of estimation improves with increasing congestion for the same overhead, which makes the use of trace packets suited to satellite links where overhead is expensive and there is minimal processing power at remote networks. Simulation in OPNET is used to demonstrate QoS parameter measurements using trace packets and the effectiveness of the technique with Poisson and self-similar traffic flows. It is shown that a switch from direct sampling to trace packets is beneficial at utilisations of 0.3 - 0.7, depending on traffic type.