Final answer:
The feature that allows a device to automatically adjust which RJ45 pin pairs it uses to transmit and receive data is called Auto-MDIX.
Step-by-step explanation:
The feature that allows a device to automatically adjust which RJ45 pin pairs it uses to transmit and receive data is called Auto-MDIX. Auto-MDIX stands for Automatic Medium-Dependent Interface Crossover and it is a feature found in many modern Ethernet devices.
Auto-MDIX eliminates the need for a crossover cable when connecting devices together. In the past, when connecting two devices, such as a computer and a switch, a crossover cable was required to ensure that the transmit pins on one device were connected to the receive pins on the other device. However, with Auto-MDIX, devices are able to automatically detect the cable type and adjust their transmitters and receivers accordingly.
For example, if you were to connect a computer to a switch using a straight-through cable, which has the transmit pins connected to the transmit pins and the receive pins connected to the receive pins, the switch and the computer would both detect this and adjust accordingly to ensure proper communication.