Buffering system for use in a communication switch that includes a multiprocessor control block and method therefore

摘要

A buffering system in a communication switch and method therefore is presented that utilizes notification of congested points within the switch to perform intelligent routing decisions such that the congestion is avoided when possible. In one embodiment, this is accomplished by detecting congestion in a transmit queue corresponding to a line card or a link layer processor of the communication switch. Upon detection of such congestion, an indication of the congestion is provided to a central control block that performs call processing and routing for the communication switch. When the central control block performs subsequent routing operations, the central control block considers the congestion indications it has thus far received such that the congested points within the switch are avoided if possible. Techniques are also presented for isolating congestion within the switch to predetermined congestion points, where when congestion occurs at these predetermined points, specific circuitry is included to help ensure that the congestion is controlled.