摘要 |
An improved combined Switching Data Unit (SDU) queuing discipline for unicast and multicast (Protocol Data Unit) PDU forwarding at a switching node is provided. Multicast SDU descriptors are replicated and stored in entries of a First-In/First-Out queue portion of a hybrid output port queue. Unicast SDU descriptors are chained in entries of a linked list queue portion of the hybrid output port queue. Servicing of the hybrid queue uses hybrid queue counters, and inter-departure-counters stored in multicast FIFO queue entries to keep track of the number of unicast SDU linked list entries, to be serviced between the multicast FIFO queue entries. The combined hybrid queue derives storage efficiency benefits from linking unicast PDUs in linked lists and further derives benefits from a simple access to multicast PDU entries.
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