Simple question about ethernet cables... Crossover or straight?

[rikadik]

I'm buying a 20m cable to put my wireless router in a better position in the house, but I'm not sure whether to use crossover or straight.

Which should I use?

Does it matter?

I didn't even realise there were different types. I'd be interested to learn what the difference is and what the need for different types is.

Many thanks!

 

[nweaver]

straight...

different types of devices are straight, same are crossed.

 

[rikadik]

Thanks!

 

[ch33zw1z]

The need for different type comes from pairs used to send and receive data. If two different devices are sending + receiving on the same pairs...then you won't be able to establish a network connection, thus the need for a crossover cable which does nothing more but change the pair positions from one end to the next so send+receive are on different pins.

The port you plug the cable into can be either MDI or MDIX, either way you don't really need to worry about it. Many ports are autosensing, and will automatically change pinouts to accomodate.

Here's a basic on how it works assuming ports are not autosensing.

NIC to NIC, switch to switch, crossover
NIC to switch, straight through.

Modem to Router, straight through.

for more info, google EIA/TIA 568a 568b, you'll find stuff on network cabling...probably explaining it better than me lol