Abstract: A method and system for detecting and controlling congestion in a multi-port shared memory switch in a communications network. The proposed congestion management scheme implements a local and a global congestion monitoring process. The local monitoring process monitors the queue depth. When the queue depth for any queue exceeds a queue length threshold a congestion control mechanism is implemented to limit incoming data traffic destined for that queue. Additionally, the global congestion monitoring process monitors the shared memory buffer and if the traffic thereto exceeds a shared memory buffer threshold a congestion control mechanism limits incoming traffic destined for any output queue which has been exceeding a fair share threshold value.

Abstract: In a method of fair queue servicing at a queuing point in a multi-service class packet switched network, incoming packets are received in buffers and outgoing packets are scheduled by a weighted fair queue scheduler. Real-time information of buffer usage along with the minimum bandwidth requirement is used to dynamically modify the weights of the weighted fair queue scheduler.

Abstract: A modification to the “leaky bucket” algorithm provides fair treatment of Frame Relay packets of varying length. The previously known leaky bucket scheme requires that there be sufficient credits in either the committed burst (Bc) bucket or excess burst (Be) bucket to accommodate the entire frame at an access point for the frame to be accepted. The “elastic leaky bucket” algorithm of the present invention permits acceptance of frames if there are any credits at all in the relevant buckets. This provides for fair treatment of long frames.

Abstract: In a method of fair queue servicing at a queuing point in a multi-service class packet switched network, incoming packets are received in buffers and outgoing packets are scheduled by a weighted fair queue scheduler. Real-time information of buffer usage along with the minimum bandwidth requirement is used to dynamically modify the weights of the weighted fair queue scheduler.

Abstract: A method is disclosed for traffic policing in packet-based, broadband networks, such as ATM networks. The method comprises the steps of monitoring the arrival of incoming cells, and advancing a reference clock on a step of I if an arrival is late but not later than I, where I is an increment, and if an arrival is later than I assuming a new busy period and setting the reference clock at the arrival time.