A network technician needs to connect two Cisco switches directly to each other using a standard Ethernet cable (straight-through). However, both switches are configured to use Auto-MDIX. What will be the outcome of this connection?
- AThe connection will be established, but it will operate in half-duplex mode due to MDIX mismatch.
- BThe connection will fail because a crossover cable is required for switch-to-switch connections.
- CThe switches will detect a loop and shut down the ports to prevent network instability.
- DThe connection will succeed because Auto-MDIX will automatically configure the correct pinouts.
Show answer & explanationAnswer & explanation
Correct answer: D. The connection will succeed because Auto-MDIX will automatically configure the correct pinouts.
Auto-MDIX (Automatic Medium-Dependent Interface Crossover) is a feature on modern network devices that automatically detects the required cable type (straight-through or crossover) and adjusts the internal pinouts of the interface accordingly. With both switches having Auto-MDIX enabled, a straight-through cable can be used for a switch-to-switch connection, which would traditionally require a crossover cable.
Why the other options are wrong
- A. Duplex mode is negotiated separately from MDIX. Auto-MDIX resolves the wiring, not the duplex.
- B. This statement is true for older devices without Auto-MDIX, but false for devices with it enabled.
- C. Auto-MDIX is for cable type detection, not loop prevention. Loop prevention mechanisms like STP would handle loops.
Auto-MDIX
Automatic Medium-Dependent Interface Crossover (Auto-MDIX) is a feature on network devices that automatically detects the cable type (straight-through or crossover) and configures the interface's transmit and receive pairs accordingly.
- Eliminates the need to use specific cable types (straight-through vs. crossover) for different connections.
- Simplifies cabling, as any standard Ethernet cable can be used for most connections.
- Must be enabled on both ends for guaranteed operation, though often enabled by default.
Memory trick: Auto-MDIX Makes Wiring Easy, No Need for Crossover or Straight-Through Worry.