<Li> Congestion: When a cut - through switch decides a frame from one incoming port needs to go out through an outgoing port, but that outgoing port is already busy sending a frame from a second incoming port, the switch must buffer some or all of the frame from the first incoming port . </Li> <P> Cut - through switching is the dominant switching architecture in Fibre Channel due to the low - latency performance required for SCSI traffic . Brocade has implemented cut - through switching in its Fibre Channel ASICs since the 1990s and has been implemented in tens of millions of ports in production SANs worldwide . CRC errors are detected in a cut - through switch and indicated by marking the corrupted frame EOF field as "invalid". The destination devices (host or storage) sees the invalid EOF and discards the frame prior to sending it to the application or LUN . Discarding corrupted frames by the destination device is a 100% reliable method for error handling and is mandated by Fibre Channel standards driven by Technical Committee T11 . Discarding corrupted frames at the destination device also minimizes the time to recover bad frames . As soon as the destination device receives the EOF marker as "invalid", recovery of the corrupted frame can begin . With store and forward, the corrupted frame is discarded at the switch forcing a SCSI timeout and a SCSI retry for recovery that can result in delays of tens of seconds. switch is the best networking device . </P> <P> Cut - through switching was one of the important features of IP networks using ATM networks since the edge routers of the ATM network were able to use cell switching through the core of the network with low latency at all points . With higher speed links, this has become less of a problem since packet latency has become much smaller . </P> <P> Cut - through switching is very popular in InfiniBand networks, since these are often deployed in environments where latency is a prime concern, such as supercomputer clusters . </P>

Switching modes cut-through fragment-free and store and forward