Stateless call admission and call preemption with a single metering and marking scheme

Apparatus for call admission and preemption, the apparatus configured for operation in a network comprising an ingress node and an egress node defining an ingress/egress node pair, and one or more core nodes located in a path between the ingress node and the egress node and configured to mark packets exceeding an admission threshold, the apparatus comprising:

• a processor;
• and
• a memory that stores instructions for execution by said processor, said instructions comprising:
• code that calculates a sustainable preemption rate by multiplying a rate of traffic received at the egress node from the ingress node that passed through the one or more core nodes without being marked by a ratio between a preemption threshold and said admission threshold;
• and
• code that, if a traffic load to the egress node is greater than said sustainable preemption rate, causes dropping of at least some traffic so that said traffic load does not exceed said sustainable preemption rate for the ingress/egress node pair.