crossover cable

carl_townshend · ‎07-20-2007

Hi all, is there any reason why we use a crossover between switches ? why cant we use a straight through cable if they support full duplex ?

mohammedmahmoud · ‎07-20-2007

Hi Carl,

Crossover cables are used between switches in order to connect Tx1 to Rx2 and vice versa (in order for the switches to exchange traffic), however there is a feature called AutoMDIX can do the crossover automatically but it is not supported in all switches.

HTH,

Mohammed Mahmoud.

royalblues · ‎07-20-2007

Carl,

Connection between switches use cross-over cables.

But new switches use the auto mdix function and hence it is not necessary nowadays

http://cciepursuit.wordpress.com/2007/07/08/switch-cabling-and-auto-mdix/

HTH

Narayan

carl_townshend · ‎07-20-2007

how come we dont need this when say connecting a pc to a switch then ?

mohammedmahmoud · ‎07-20-2007

Hi Carl,

Hubs and switches are deliberately wired opposite the way end stations are wired, so that when a hub or switch is connected to an end station, a "straight through" ethernet cable can be used and the pairs will match up properly. When two hub/switches are connected to each other, or two end stations are connected to each other, a "crossover" cable is used to make sure that the correct pairs are connected.

HTH,

Mohammed Mahmoud.