Cisco CCNA (200-301)Network FundamentalsMedium
A network administrator wants to connect two Cisco switches directly using a standard Ethernet cable. Both switches are modern, supporting auto-MDIX. Which type of Ethernet cable should be used?
- AStraight-through cable
- BRollover cable
- CCrossover cable
- DCoaxial cable
Show answer & explanationAnswer & explanation
Correct answer: A. Straight-through cable
Modern switches with auto-MDIX (Automatic Medium-Dependent Interface Crossover) capability can automatically detect the required cable type and adjust their transmit/receive pairs accordingly. This means that a straight-through cable can be used for any connection, whether it's switch-to-switch or switch-to-host, eliminating the need for crossover cables.
Why the other options are wrong
- B. A rollover cable (console cable) is used for connecting a computer's serial port to a router/switch console port, not for Ethernet data connections.
- C. A crossover cable was traditionally needed for switch-to-switch connections, but auto-MDIX removes this requirement.
- D. Coaxial cables are not used for modern Ethernet switch connections.
Auto-MDIX
Auto-MDIX (Automatic Medium-Dependent Interface Crossover) is a feature on modern network devices that automatically detects and configures the Ethernet cable type (straight-through or crossover) for a correct connection.
- Eliminates the need to manually choose cable type.
- Allows straight-through cables for all connections.
- Common on modern switches, routers, and NICs.
Memory trick: Auto-MDIX means 'Auto-Magic', so just use a straight-through cable!