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Filtering
Filtering is important for a LAN switch. Filters can be used to reduce broadcast traffic, block certain protocols and provide security functions.
The SmartStack
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Destination or source MAC addresses
Destination service access point (DSAP)
Subnetwork Access Protocol (SNAP) type
Each protocol filter can be applied on a
Source and destination MAC address filtering can be applied to all incoming frames. The MAC address filters act in one of three ways:
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Block destination address at a specific
Allow destination address at specific
Force destination address to a specific
Congestion Control
At regular intervals, the switch CPU inspects the queues on all output ports. If a queue size is above a certain threshold, the port is instructed to:
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Set the transmit priority for low priority frames to a specified high level
Delete old frames from the queue until it reaches a specified size
When the queue size again comes below a normal threshold size the port is instructed to set the transmit priority back to the normal level.
SmartStack | Switch Overview |