Point-to-multipoint arbitration

A method for point-to-multipoint transmission of a unit of data in a network switch comprising the steps of:

• in a first storing step, storing a representation of said unit of data, including an identification of output ports designated for receipt of said unit of data, in a request list;
• in a second storing step, storing a representation of dynamic bandwidth that represents both unallocated bandwidth and unused-allocated bandwidth in an allocation list;
• comparing the request list to the allocation list to determine if a match therebetween exists;
• and
• transmitting said unit of data when a match is determined to exist.

An asynchronous transfer mode ("ATM") switch for controlling a plurality of connections and transmitting an enqueued cell associated with one of said plurality of connections from a single input port to a plurality of designated output ports, comprising:

• a first memory for temporarily storing said enqueued cell, a first portion of said first memory being reserved for use by at least one connection of the plurality of connections and a second portion of said first memory being shared by a portion of the plurality of connections;
• a second memory containing an identification of unassigned output ports at specified time intervals at which dynamically available memory occurs in the reserved portion of memory and the shared portion of memory;
• and
• an arbiter circuit which controls allocation of the dynamically available memory to the plurality of connections, said arbiter circuit maintaining a record of the designated output ports and being operative to compare said identification of unassigned output ports to said record of designated output ports to identify a match therebetween, corresponding to a time at which said enqueued cell may be transmitted to a selected one of said plurality of designated output ports, said switch being operative to transmit said enqueued cell upon identification of said match.