Eusso USH5016-XPC, Руководство пользователя

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4. Switch Operation
4.1 MAC Address Table and Learning
The switch is implemented with a MAC address table, which
is composed of many entries. Each entry is used to store the
address information of network nodes on the network,
including MAC address, port ID, etc. The information is the
most important base to do packet filtering and forwarding.
When one packet comes in from any port, the switch will learn
the source address, port ID, and the other related information
in address table. Therefore, the content of the MAC table will
update dynamically.
4.2 Filtering and Forwarding
When one packet comes in from any port of the switch, it will
check the destination address besides the source address
learning. The switch will look up the address table for the
destination address. If not found, this packet will be forwarded
to all the other ports except the port where this packet comes
in. If found, and the destination address is located at different
port from this packet comes in, the packet will be forwarded to
the port where this destination address is located according to
the information of address table. But, if the destination
address is located at the same port as this packet comes in
then this packet will be filtered.
4.3 Store and Forward
Store-and-forward is one kind of packet-forwarding
methodology. As a store-and-forward switch, it will store the
complete packet in the internal buffer and do the complete
error checking before transmitting to the network. Therefore,
no error packets will disturb the network. It is the best choice
when a network needs efficiency and stability.