WEEK 5: Cross Over and Straight Through - M199205zn/Datacomm-CS3 GitHub Wiki

When testing crossover and straight-through cables using a network cable tester, the connection results will differ based on the wiring standard used. Here’s what you can expect:

1. Straight-Through Cable Test Result:

A straight-through cable follows the same wiring standard on both ends (either T568A to T568A or T568B to T568B).

  • When tested with a cable tester, the lights on both ends will light up in the exact same sequence (1β†’1, 2β†’2, 3β†’3, ..., 8β†’8).
  • This indicates that the cable is correctly wired for typical connections like PC to Switch, Router to Switch, or PC to Hub.

2. Crossover Cable Test Result:

A crossover cable follows T568A on one end and T568B on the other end. This swaps the transmission (TX) and receiving (RX) pairs.

  • The tester will show a swapped sequence:
    • Pin 1 β†’ Pin 3
    • Pin 2 β†’ Pin 6
    • Pin 3 β†’ Pin 1
    • Pin 6 β†’ Pin 2
    • Pins 4, 5, 7, and 8 remain unchanged.
  • This indicates that the cable is correctly wired for direct PC to PC, Switch to Switch, or Router to Router connections.

If the tester shows no continuity or wrong mappings, the cable might have improper wiring or a faulty crimp.