Chapter 4
Switch Operation
Address Table
The Industrial Gigabit Ethernet Switch is implemented with an address table. This
address table is composed of many entries. Each entry is used to store the address
information of some node in network, including MAC address, port no., etc. This
information is automatically obtained by the Industrial Gigabit Ethernet Switch.
Learning
When one packet comes in from any port. The Industrial Gigabit Ethernet Switch will
record the source address,and port number, and the other related information in
address table. This information will be used to decide either forwarding or filtering for
future packets.
Forwarding & Filtering
When one packet comes from some port of the Industrial Fast Ethernet Switch, it will
also check the destination address besides the source address. The Industrial Fast
Ethernet Switch will lookup the address-table for the destination address. If not found,
this packet will be forwarded to all the other ports except the port from which this
packet comes in. And these ports will transmit this packet to the network it is
connected to. If found, and the destination address is located at a different port from
where this packet comes in, the Industrial Fast Ethernet Switch will forward this
packet to the port where this destination address is located, according to the
GE-DSG-8 DSGH-5 and 8 Ethernet Switch User Manual
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