Method and apparatus for ATM switching

摘要

PCT No. PCT/EP95/00276 Sec. 371 Date Jul. 7, 1997 Sec. 102(e) Date Jul. 7, 1997 PCT Filed Jan. 26, 1995 PCT Pub. No. WO96/23391 PCT Pub. Date Aug. 1, 1996A switch for use in an ATM network is disclosed. The switch is designed to perform a function beyond that normally achievable with a virtual path switch functioning in accordance with the ATM standard. The switch according to the invention has data stored in a look-up table (431-433) which allows it to identify communication cells of particular individual virtual channels, indicated by the virtual path identifier (VCI), although these cells cannot be distinguished on the basis of their virtual path indicators (VPIs). This identification is attempted before the usual step of forwarding an incoming communication cell based solely on its virtual path indicator. A priority circuitry (44) ensures that entries associated with the combined VPI/VCI is given a priority over those associated only with the VPI. The switch can extract cells of individual virtual channels passing through it. It can also insert virtual channels into the ATM network.