10-23-2011 02:15 AM - edited 03-07-2019 02:59 AM
Why was the decision made to let PCs/routers/APs transmit on pin 1 and 2, and hubs/switches on pin 3 and 6?. If all devices transmit on the same pins, we could just always use crossover cables. The would also be no need for Auto-MDIX. Wouldn't that make life easier?
10-23-2011 02:09 PM
The would also be no need for Auto-MDIX. Wouldn't that make life easier?
Are you saying that disable MDI/MDI-X would make life easier? I disagree. MDI/MDI-X certainly makes things alot easier and I've been enjoying this feature since it was first rolled out with the 3750!
10-24-2011 03:18 AM
Currently Being Moderated
Streight/Crossover cable
Why was the decision made to let PCs/routers/APs transmit on pin 1 and 2, and hubs/switches on pin 3 and 6?. If all devices transmit on the same pins, we could just always use crossover cables. The would also be no need for Auto-MDIX. Wouldn't that make life easier?
A medium dependent interface (MDI) describes the interface (both physical and electrical) in a computer network from a physical layer implementation to the physical medium used to carry the transmission. Ethernet over twisted pair also defines a medium dependent interface crossover (MDIX) interface.
The X refers to the fact that transmit wires on an MDI device must be connected to receive wires on an MDIX device. Straight through cables connect pins 1 and 2 (transmit) on an MDI device to pins 1 and 2 (receive) on an MDIX device. Similarly pins 3 and 6 are receive on an MDI device and transmit on an MDIX device.
The general convention was for network hubs and switches to use the MDIX configuration, while all other nodes such as personal computers, workstations, servers and routers used an MDI interface.
Hope to Help !!
Ganeshh Iyer
10-25-2011 05:37 AM
Sure, but if we would only have MDIX we could always use crossover cables. Right?
10-25-2011 03:39 PM
Sure, but if we would only have MDIX we could always use crossover cables. Right?
Sure you can. As long as you have one in handy whenever you need it.
10-25-2011 05:55 PM
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Pieter Verberne wrote:
Sure, but if we would only have MDIX we could always use crossover cables. Right?
MDIXMDIXMDIXMDIXMDIX
Yes and it would also be true if all devices had MDI.
10-25-2011 11:40 PM
Uhm, yes right :-)
But there has to be a reason why both MDI and MDIX are both in use. What could be the reason? What is the advantage of using both MDI and MDIX.
10-26-2011 02:15 AM
Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
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But there has to be a reason why both MDI and MDIX are both in use. What could be the reason? What is the advantage of using both MDI and MDIX.
That's a good question! MDI to MDIX allows use of of a straight through cable. I'm unaware of any technical reason why such a cable would be better than a crossover cable, but perhaps there is on.
Otherwise, it might just be something like that just how it has been done for other communication cables that are logically DTE/DCE where their ports swap pins too.
10-26-2011 02:23 AM
What is the advantage of using both MDI and MDIX.
It minimizes engineers paying money into the "swear jar" when they go "Where the
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