Actually during auto-negotiation one pair transmits fast link pulses and another pair receives them. The same basic AN protocol is used for 10/100/1000, gigabit just has some additional pages. So gigabit phys generally do support MDI/MDIX as well as auto-mdix, but the need goes away when link comes up at 1G.
Jim -----Original Message----- From: cisco-nsp [mailto:[email protected]] On Behalf Of Daniele Orlandi Sent: Wednesday, March 19, 2014 1:05 PM To: [email protected] Subject: Re: [c-nsp] NPE-G1s don't want to talk to each other over copper? On 03/19/2014 05:45 PM, Lukas Tribus wrote: > > Its correct that GigabitEthernet mandates autoneg, and it is also > correct that "mdix auto" REQUIRES autoneg, but afaik that doesn't mean > all your gigabit/autoneg gear can also automatically do auto-mdix, > because that probably requires different hardware (switching RX/TX). GBE does not have a MDI/MDI-X concept since every pair is used for RX and TX at the same time. There is no such thing as a "Gigabit crossover cable". Bye, _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
