GarrettCom CS14 - Manual (Page 27)

CS14 & CSN14 Series Converter Switches Installation and User Guide (09/09)
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bad packets, enabling all of the available bandwidth to be used for valid information.
While other switching technologies such as "cut-through" or "express" impose
minimal frame latency, they will also permit bad frames to propagate out to the Ethernet
segments connected. The "cut-through" technique permits collision fragment frames,
which are a result of late collisions, to be forwarded to add to the network traffic. Since
there is no way to filter frames with a bad CRC (the entire frame must be present in order
for CRC to be calculated), the result of indiscriminate cut-through forwarding is greater
traffic congestion, especially at peak activity. Since collisions and bad packets are more
likely when traffic is heavy, the result of store-and-forward operation is that more
bandwidth is available for good packets when the traffic load is greatest.
To minimize the possibility of dropping frames on congested ports, each
Magnum CS14 & CSN14 Series Converter Switch dynamically allocates buffer space from
128Kb memory pool, ensuring that heavily used ports receive very large buffer space for
packet storage. (Many other switches have their packet buffer storage space divided evenly
across all ports, resulting in a small, fixed number of packets to be stored per port. When
the port buffer fills up, dropped packets result.) This dynamic buffer allocation provides the