LAN Connection Facts

When connecting devices in a LAN, you will need to use different types of Ethernet cables. You will need to know the pin positions of the cable types to differentiate them from each other. The types of Ethernet cables used for LAN connections include the following:

Type

Pin Position

Uses


Straight-through Ethernet Cable

1 --> 1
2 --> 2
3 --> 3
6 --> 6

Use a straight-through Ethernet cable when connecting the following devices:

  • Workstation to hub
  • Workstation to switch
  • Router to hub
  • Router to switch


Crossover Ethernet Cable

1 --> 3
2 --> 6
3 --> 1
6 --> 2

Use a crossover Ethernet cable when connecting the following devices:

  • Switch to switch
  • Switch to hub
  • Hub to hub
  • Workstation to router
  • Workstation to workstation
  • Router to router

Be aware of the following when making LAN connections:

  • Through Auto-MDI/MDIX, newer switches can determine what type of Ethernet cable is needed and will internally change the sending/receiving pin positions if needed.
  • Some Cisco routers provide a generic Attachment Unit Interface (AUI) port. The AUI port is designed to connect to an external transceiver for conversion to a specific media type, such as coaxial or fiber optic.
  • To support LAN distances above twisted pair Ethernet limits (>100 meters), use the switch's SFP slot (a Gigabit uplink port) and fiber optic media.

 

Credit: Testout 640-802 CCNA Notes