Implementation of VirtualClock Scheduling Algorithm in OPNET
In today’s high-speed packet networks that support various applications with different service requirements, congestion control is an important issue. One of the methods for
preventing congestion is packet scheduling. Packet scheduling in routers can provide guaranteed performance in terms of delay, delay jitter, packet loss, and throughput.
In this paper, we describe the OPNET model of an IP router with a scheduling algorithm called VirtualClock. The VirtualClock algorithm monitors the average transmission rates of packet data flows. It also provides each flow with a guaranteed throughput and a low queuing delay. We have incorporated the VirtualClock algorithm into the OPNET process model ip_output_iface. This process model executes scheduling algorithms in the network layer of IP objects.