Apparatus and method in a network switch for modifying a bandwidth request between a requestor and a router

Abstract

A network switch, configured for performing layer and layer switching in an Ethernet (IEEE 802.3) network without blocking of incoming data packets, includes a network switch port having a filter (i.e., a packet classifier module) configured for evaluating an incoming data packet on an instantaneous basis. The filter performs simultaneous comparisons between the incoming data stream of the data packet and multiple templates configured for identifying respective data protocols. The network switch uses the filter to detect the presence of an RFC 2205 compliant bandwidth reservation message from a host computer for reception by a router. The network switch is configured for selectively changing a requested quality of service specified in the bandwidth reservation message, based on a determined absence of available resources within the network switch. The network switch selectively increases the requested quality service, based on the determined absence of the available resources, to a value that will be denied by the router. Hence, the network switch can ensure that a router does not grant a bandwidth reservation message from a host computer that would cause the capacity of the network switch to be exceeded, without any modification to the host computer or the router, or any interference with the resource reservation protocol specified in RFC 2205.