Patent ID: 6801953
Filing Date: 2004-10-05
Classification: H04L

Abstract:
Communication apparatus for a computer network employing addressed data packets, comprising:a stack of communication devices each of which has a multiplicity of ports for forwarding data packets to said computer network and receiving data packets from said computer network; a cascade connection which is connected to at least one cascade port of each of said communication devices, said cascade connection providing transmission of data packets between the communication devices; and at least one trunk connection, constituted by a plurality of links for the sending of addressed data packets, each of said links extending from a further communication device to a respective port in a set of ports, other than any cascade port, the ports in said set of ports being located on more than one communication device in said stack; whereby a communication device in said stack can receive data packets both directly from said further communication device and also indirectly from said further communication device by way of said cascade connection; and wherein each communication device transmits on the cascade connection addressed packets with a respective indication whether said addressed data packets have been received at a port in the trunk connection and each communication device is arranged for responding to such an indication received with addressed data packets from said cascade connection whereby to recognize such addressed packets as coming from said further communication device by way of said trunk.