Packet router having a hierarchical buffer structure

Abstract

A packet-router architecture in which buffer modules are interconnected by one or more interconnect fabrics and arranged to form a plurality of hierarchical buffer levels, with each higher buffer level having more buffer modules than a corresponding lower buffer level. An interconnect fabric is configured to connect three or more respective buffer modules, with one of these buffer modules belonging to one buffer level and the other two or more buffer modules belonging to a next higher buffer level. A buffer module is configured to implement a packet queue that (i) enqueues received packets at the end of the queue in the order of their arrival to the buffer module, (ii) dequeues packets from the head of the queue, and (iii) advances packets toward the head of the queue when the buffer module transmits one or more packets to the higher buffer level or to a respective set of output ports connected to the buffer module.