Some Notes on Using Crossover or Straight-through Ethernet Cables

UTP Cables for 10BASE-T and 100BASE-TX - Just to make it easier for me to remember how cabling works specifically for Crossover and Straight-through I've decided to jot down a few notes for quick reference...


Ethernet straight-through cable connects using the following combinations:

• Switch to Router
• Switch to PC or Server
• Switch to WAP (Ethernet interface)
• Switch to LAN Networked printer
• Hub to PC or Server
• Hub to Router
• Hub to WAP (Ethernet interface)
• Hub to LAN Networked printer

Ethernet crossover cable connects the following:

• PC to PC, Server to Server, PC to Server
• Hub to Hub
• Switch to Switch
• Switch to Hub
• Router to Router
• Router to PC, Server
• Router to WAP (Ethernet interface)
• Router to LAN Networked printer
• PC or Server to LAN Networked printer
• PC or Server to WAP (Ethernet interface)
• LAN Networked printer to WAP (Ethernet interface)
• WAP (Ethernet Interface) to WAP (Ethernet interface)

It may also help to think of it using the following tables :

Devices That Transmit on pins 1,2 and Receive on 3,6

• PC, Servers
• Routers
• WAPs (Ethernet interface)
• LAN Networked printers

Devices That Transmit on pins 3,6 and Receive on 1,2

• Hubs
• Switches

A device connected to another device using the same pin assignments must use a crossover cable, otherwise use a straight-through cable.


A simpler way:



Crossover Cable
Switch-Switch
Switch-Hub
Hub-Hub
Router-Router
PC-Router
PC-PC

Straight-Through Cable
Router-Switch
PC-Switch
Server-Switch
PC-Hub
Server-Hub