Telsey Telecommunications
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MDI, while a twisted pair port on a switch or hubs is usually MDI-X. To connect two 10 Mbps or 100 Mbps
network devices together that have dissimilar port wiring configurations, such as an MDI to MDI-X, you
would use a straight-through twisted pair cable. To connect two networks devices that have the same
wiring configuration, such as MDI to MDI, you would use a crossover cable.
The Switch features automatic MDI/MDI-X. The RJ-45 port automatically determines the configurations
of the port on the device to which it is connected and then configures itself appropriately.
MAC Address Table
The heart of an Ethernet switch is the Media Access Control (MAC) address table. Every device that you
attach to an Ethernet network has a MAC address. This address is assigned to the device by the device’s
manufacturer.
The switch creates the MAC address table by examining the frames that it receives on its ports. The
switch checks to determine whether the address is already in its MAC address table. If it is not, the switch
adds the address to the table along with the port number on which the frame was received.
The switch also checks the destination MAC address of each frame it receives. If the destination address
is not in the MAC address table, the switch broadcasts the frame to all switch ports.
The MAC address table in the switch can store and update periodically up to 2,000 MAC addresses.
