Patent ID: 6064674
Filing Date: 2000-05-16
Classification: H04L

Abstract:
A local area network (LAN) switching apparatus for interconnecting a LAN segment to an Asynchronous Transfer Mode (ATM) network, comprising:a plurality of LAN ports, wherein each LAN port connects one unique LAN segment to a LAN switch;at least one ATM port, wherein each ATM port of the LAN switch interfaces to the ATM network;a connection means for establishing a plurality of connection paths simultaneously, wherein each said connection path establishes a connection through the switching apparatus between any two or more of the plurality of LAN ports and ATM ports, said connection path for transmitting data comprising LAN frames;a data transmission means for formatting data for transmission over said LAN into standard LAN frames in compliance with the international standard of Open Systems Interconnection (OSI), wherein said standard provides a universally applicable layered architecture containing seven layers, numbered from 1 to 7, with each layer having a set of defined functions and providing a set of services to and from the adjacent two layers; anda LAN to ATM format conversion means for changing the format of data as it traverses the LAN switch from LAN port to switch to ATM port, wherein LAN frames are converted to switch frames for transfer through the switching apparatus and switch frames are converted to ATM frames in preparation for transfer to the ATM network;an ATM adapting apparatus for converting ATM frames to ATM cells and ATM cells to ATM frames, wherein ATM cells are created by segmenting said ATM frame into sequential ATM cells and ATM frames can be created by assembling sequential ATM cells into an ATM frame;an ATM to LAN format converter for changing the format of data traversing the LAN switch from ATM port to switch to LAN port, wherein ATM frames are converted to switch frames for transfer through the switching apparatus and switch frames are converted to LAN frames for transfer to the LAN port;a first multiprotocol processing means for converting either layer 2 or layer 3 of the OSI standard from LAN frames to switch frames to ATM frames, wherein LAN frames are compatible with LAN protocol and ATM frames are compatible with the first ATM adapting apparatus protocola second multiprotocol processing means for converting either the layer 2 or layer 3 of the OSI standard from ATM frames to switch frames to LAN frames; anda sorter for the ATM port for sorting LAN frames arriving from said switch connection path and ATM frames arriving from the ATM network into a first category of routed frames wherein layer 3 of the OSI standard is converted from LAN frame format to ATM frame format or from ATM frame format to LAN frame format or a second category of bridged frames wherein layer 2 of the OSI standard is converted from LAN frame format to ATM frame format or from ATM frame format to LAN frame format or a third category of frames which should be discarded as containing errors rather than being routed or bridged.