Broadly speaking, an apparatus for efficiently utilizing a shared packet
buffer memory in a switch and a method for operating the same is
provided. More specifically, the apparatus includes a memory having a
number of buffers configured to be operated in a ratcheted manner. The
ratcheted manner in which the memory is operated causes each incoming
data stream to be distributed across the number of buffers. Each stored
data stream can also be retrieved from the number of buffers for output
from the memory in a similar ratcheted manner. The memory uses a rotating
selector to control the ratcheted manner of operation. Also, the memory
is capable of simultaneously servicing each of a number of inputs and a
number of outputs to which the memory is connected.