Quality of service (QoS) marking is one of the media management options that Office Communications Server supports. QoS marking is used to differentiate the paths that packets take over the Internet. Routers that perform QoS checking examine the headers of packets in order to determine how they should be routed for the best quality of service. Although Office Communicator Server has been designed to work without any QoS framework, it is possible to configure the media stack to mark the IP traffic conveying the real time audio and video IP traffic according to well established classes of services.
The marking may be enabled or disabled by means of registry keys. If enabled, the marking of the IP packets is done by the QoS Packet Scheduler service and is applied to media ports independently of the protocol used to deliver the audio/video traffic. The resulting marked packets can subsequently be recognized by network entities (end systems and routers) to manage the media traffic according to the QoS priorities.