Netgear DG834v1 – ADSL Modem Router Manual De Referência

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Reference Manual for the Model DG834 ADSL Firewall Router
Network and Routing Basics
B-13
 
Inside Twisted Pair Cables
For two devices to communicate, the transmitter of each device must be connected to the receiver 
of the other device. The crossover function is usually implemented internally as part of the 
circuitry in the device. Computers and workstation adapter cards are usually media-dependent 
interface ports, called MDI or uplink ports. Most repeaters and switch ports are configured as 
media-dependent interfaces with built-in crossover ports, called MDI-X or normal ports.  Auto 
Uplink technology automatically senses which connection, MDI or MDI-X, is needed and makes 
the right connection.
Figure B-1
 illustrates straight-through twisted pair cable.
Figure B-1:  Straight-Through Twisted-Pair Cable
Figure B-2
 illustrates crossover twisted pair cable.
Figure B-2:  Crossover Twisted-Pair Cable