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Ideal Lantek 7 is capable to 750 MHz Sterling Vaden Rehan -com wrote: Beside ANEXT how we are going to verify 625 MHz field testing? There are no UTP field test equipment that can test up to 650 MHz today. Rehan Mahmood Hubbell Premise Wiring"Cobb, Terry R (Terry)" <tcobb@avaya.com> 08/04/03 05:58PM >>>Dan, The biggest problem is that you can not determine the potential Alien Crosstalk. It can show up at anytime and can not be realistically tested in the field. Terry -----Original Message----- From: Booth, Bradley [mailto:bradley.booth@intel.com] Sent: Monday, August 04, 2003 4:26 PM To: stds-802-3-10gbt@ieee.org Subject: RE: [10GBASE-T] Technical feasibility: AutoNegotiation Dan, Interesting that you'd ask this, because it was a question I had a meeting or two ago. In most cases, the PHYs can determine the link length via a simple electronic ping. As for the grade of the cable, extrapolation could be performed during the training sequence as the number of taps would have a correlation to the quality of the cable and the data rate or distance supported. A lot of these methods are in use today for 1000BASE-T, but they are implementation strategies, not based on what is in 802.3. Cheers, Brad -----Original Message----- From: DOVE,DANIEL J (HP-Roseville,ex1) [mailto:dan.dove@hp.com] Sent: Monday, August 04, 2003 3:49 PM To: stds-802-3-10gbt@ieee.org Subject: RE: [10GBASE-T] Technical feasibility: AutoNegotiation Hello, Perhaps someone can give me a quick pointer on how we are going to address the issue of <100m cable plants that meet ISO 11801 specs not being able to support 10GBASE-T. For example, I have a building full of CAT5e and CAT6 cables. The cables were installed to specification. Now, all I see are patch panels and wall jacks. I don't have a record of which cable is how long, or what its electrical specs are. The current Auto-Negotiation protocol supports HCD resolution which means that the link, if configured to 10GBASE-T, will resolve to that speed if both ends of the link support it. However, if the cable (85m of CAT6) does not, the link will bounce up and down as it negotiates to speed, then fails to link. Maybe even worse is the link that actually comes up, but operates unreliably due to thermal variation causing changes in parametric values and suffers excessive BER or drops link occasionally. What is the fix? Do I test the wire in advance of using 10GBASE-T? Do we fix the Auto-Negotiation protocol to automatically drop speed if the SNR gets too low to guarantee the BER? If these have already been addressed, please feel free to just send the URL to the presentation. Regards, Dan Dove HP ProCurve Networking |