Gigafast EE2400-G, Руководство пользователя

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3-e Pin Assignments for straight-through cabling
In some circumstances, however, crossover cables may be required. If a
station port on your switch must connect to a hub/switch, you must use a
crossover cable, which ha sits transmit (TD) and receive (RD) leads crossed
over to the other end of the cable.
Note:
The pin RJ-45 assignment used in 1000BASE-T is different from in
10/100BASE-TX. Therefore, a Switch-to-Switch 1000BASE-T connection
does not require a crossover cable.
However, the 1000BASE-T gigabit port can automatically determine whether
or not it needs to cross over between pairs. Therefore, the 1000BASE-T
gigabit port does not require an external crossover cable when connecting to
another Switch.
If EE2400-G interoperates with a device that cannot automatically correct for
crossover, it makes the necessary adjustment prior to commencing
auto-negotiation. If it interoperates with a device that implements MDI/MDIX
crossover, a random algorithm as described in IEEE802.3 section 40.4.4
determines which device performs the crossover.
3-f 10/100BASE-TX pin assignments for crossover cabling