Cabling Pin questions

[sl1210user]

Hi,

Please can you tell me if I have got this right.

PC > PC

Cable needed Crossover cable

PCs NIC transmits on Pin 1/2 and receives on 3/6. So you need to use a crossover cable to avoid transmission collisions.

i.e Transmission 1/2 from the PC NIC will be routed to receiving PINS 3/6 at the other end, and vice versa.

PC > Switch

Cable needed standard Straight through cable.

PCs NIC transmits on Pin 1/2 and the PINs on the switch port are reversed so you don't need to use a crossover cable.

i.e The PC transmits on 1/2 and is received by 3/6 at the switch, and the switch also transmits on 1/2 which corresponds to 3/6 at the PC.  

Thanks

[Reza Sharifi]

Hi,

Your descriptions are correct.  Also, note for PC > Switch scenario, it depends on the switch as some models support MDIX, meaning you can use straight or crossover to connect a PC to a switch.  The switch with MDIX capability will correct the pin issue.

http://www.cisco.com/c/en/us/td/docs/wireless/workgroup_bridge/350/installation/guide/350hig/WGBappC.html

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960x/software/15-0_2_EX/int_hw_components/configuration_guide/b_int_152ex_2960-x_cg/b_int_152ex_2960-x_cg_chapter_011.html

HTH

[sl1210user]

Thanks Reza.

I didn't know anything about MDIX, but I do now.

I will just continue to use straight cable for connecting PC>Switches even if the device supports MDIX.

Thanks