When is crossover cable required

A crossover cable redirect the output of one RJ port into the input of the other RJ port. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Why do I need a crossover cable to connect devices of the same type?

Ask Question. Asked 5 years, 2 months ago. Active 2 years, 10 months ago. Viewed 25k times. Improve this question. Wow - did you manage to post through a time tunnel from the s? I'd really have to dig to find something that didn't autosense around here, and I'm a long way from the bleeding edge most of my stuff is semi-obsolete, but not THAT obsolete. Add a comment. Active Oldest Votes. How do they fit in to the mix. Unless of course, we introduce another pair crossing in between the switches: From the image above, we can see The PC connection to the Switch does not require a crossover cable The Switch connection to the other Switch does require a crosover cable The Switch's connection to the other PC does not require a cross over cable Notice how in the diagram, with all the crossing, the path from one PC's TX wire to the other PC's RX wire is maintained.

Asked 7 years, 8 months ago. Active 4 years, 1 month ago. Viewed 21k times. Improve this question. HopelessN00b Note: Cross-over cables only applied to 10 and Mb Ethernet. Gigabit sends and receives on all 4 pairs at the same time. Why is this off-topic? ChrisS, what you describe only applies to UTP cabling. Usually, straight through cables are primarily used for connecting unlike devices. And crossover cables are use for connecting alike devices.

Use straight through Ethernet cable for the following cabling:. Straight through and crossover cables are wired differently from each other. One easy way to tell what you have is to look at the order of the colored wires inside the RJ45 connector. If the order of the wires is the same on both ends, then you have a straight through cable. At present, the straight through cable is much more popular than crossover cable and is widely used by people.

Information technology IT professionals used crossover cables often in the s and s; the popular forms of Ethernet did not support direct cable connections between hosts. Both the original and Fast Ethernet standards were designed to use specific wires to transmit and receive signals. These standards required the two endpoints to communicate through an intermediate device to avoid conflicts caused by using the same wires for both transmit and receive.

A feature of Ethernet called MDI-X provides the necessary auto-detection support to prevent these signal conflicts. Only one end of a connection needs to support auto-detection for this feature to work. Most home broadband routers even older models incorporated MDI-X support on their Ethernet interfaces. Crossover cables are needed only when connecting two Ethernet client devices, neither of which is configured for Gigabit Ethernet.

Modern Ethernet devices automatically detect the use of crossover cables and work with them seamlessly. You should only use crossover cables for direct network connections. Attempting to connect a computer to an old router or network switch with a crossover cable instead of a normal cable can prevent the link from functioning. You can purchase these cables through electronics outlets.

Hobbyists and IT professionals often prefer to make their own crossover cables instead. To convert a straight-through cable to a crossover cable, remove the connector and reattach the wires with the appropriate transmit and receive wires crossed.

Actively scan device characteristics for identification.