Straight-Through or Crossover?

About this interactive

The lesson's rule: - **MDI ports** (computers, servers, printers, routers) send on pins 1 and 2 and receive on pins 3 and 6. - **MDIX ports** (switches) receive on 1 and 2 and send on 3 and 6. - **MDI to MDIX:** straight-through. PC to switch, router to switch. - **Like to like:** crossover. PC to PC, PC to router, switch to switch, router to router. A switch's uplink port is MDI, so switch to switch through an uplink port takes a straight-through cable. Many ports today are auto MDI-X: they sense the other end and adjust, so either cable works. This drill assumes ports that cannot.

What you'll learn

Choose a straight-through or a crossover cable for a connection from the two ports it joins: MDI to MDIX is straight-through, like to like is crossover
Place devices on the right side: computers, servers, printers and routers have MDI ports; switches have MDIX ports, apart from an uplink port

Aligned to

Cisco CCNA

1.3 Compare physical interface and cabling types

Cisco CCST Networking

4.2 Use a network diagram to attach the appropriate cables

CompTIA Network+

5.2 Given a scenario, troubleshoot common cabling and physical interface issues.

Key terms

MDI: Medium Dependent Interface; a standard Ethernet interface type found on end devices such as PCs and routers where pins 1 and 2 transmit and pins 3 and 6 receive.
Straight-Through Cable: An Ethernet cable terminated with the same wiring standard (T568A or T568B) on both ends, used to connect dissimilar devices such as a computer to a switch.
Crossover Cable: An Ethernet cable terminated with T568A on one end and T568B on the other, crossing transmit and receive pairs to connect two similar devices such as computer to computer.
Auto-MDIX: A feature on network devices that automatically detects the required cable type and adjusts pin configurations accordingly, allowing either straight-through or crossover cables to be used.

Topics

Mdi Mdix Straight Through Cable Crossover Cable Interactive Streak Sort

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