Applications and users dynamically make QoS provisioning requests for individual traffic flows traversing client and server hosts. A traffic flow provisioning request is conveyed to a services manager, which determines a set of traffic attributes for the flow and determines the networks the flow traverses between the client and server hosts. The services manger then oversees the admission of the flow to appropriate traffic classes in each determined network and the obtaining of a DSCP value for each network. Lastly, the services manger conveys the DSCP value of the first network traversed back to the client or server host, depending on the direction of the flow, which host is then configured to appropriately mark the DSCP field of the traffic flow packets. In a further embodiment, the services manager also instructs the client or server host to perform packet policing and shaping for the flow.