Topology independent broadcast of cells in an atm network or the like

Abstract

A topology-independent method and apparatus for avoiding continuous looping of transmission of cells and for allowing broadcast of cells in a network implementing Asynchronous Transfer Mode ('ATM') or similar networking architectures. The disclosed method and apparatus provides for 'misusing' fields in a cell header in order to provide for information identifying a cell as a broadcast cell and to provide for 'expiration information' in the cell header. More specifically, a first station stores data in a first area of a cell intended for transmission on the network, where the first area is defined by standards to store certain information (in particular, it is defined in the preferred embodiment to store virtual path identifier information, VPI). The information stored identifies the cell as a broadcast cell. In other words, the field is 'misused' to store this information. The first station further stores in a second field, also defined by the standard to store certain information (in particular, virtual channel identifier information, VCI), information which allows for expiration of the cell. Thus, this second field is also 'misused'. The cell is then transmitted onto the network, copied and forwarded out of multiple ports of each switch, until the cell 'expires'. In the described embodiment, the 'expiration information' is implemented as a hop count.