Table of Contents
Advertisement
A
T
BOUT THE
IGER
Switch Architecture
Switching Methods
Adaptive Cut-Through
SMC's TigerSwitch 100 models employ a dynamic forwarding
architecture that enables them to support adaptive cut-through
frame forwarding mode. This approach allows the switch to
automatically alternate between three different switching
methods to provide the best possible performance in response
to current network conditions.
Cut-Through
Also known as "on-the-fly" switching, the cut-through switching
technique involves forwarding each data packet as soon as the
6 byte destination address in the header has been read. It does
not wait until the entire packet has been received. This
method, which takes up the least processing time, reduces the
latency of each packet to twenty microseconds (20 µsec) or less.
Cut-through switching mode is the default setting of each port
on the TigerSwitch 100.
Fragment-Free
This switching method is similar to cut-through, but it requires
that the first 64 bytes of the data packet be received before it is
forwarded. This enables the switch to discard runt packets -
smaller than legal size packets which are collision byproducts -
and effectively clean up the data stream. This method provides
the greatest benefit when the collision rate is high (e.g., when
the switch is used to interconnect several shared segments, each
having a large number of end stations.)
Store-and-Forward
In store-and-forward switching mode, the entire packet must be
received into a buffer and checked for validity before being
forwarded. This prevents errors from being propagated
throughout the network.
1-10
S
100
WITCH
Advertisement
Chapters
Table of Contents
