On Sun, 05 Feb 2012 13:39:39 -0600, Stan Hoeppner wrote: > On 2/4/2012 12:25 PM, Camaleón wrote: >> On Sat, 04 Feb 2012 10:36:04 -0600, John Hasler wrote: >> >>> Stan Hoeppner writes: >>>> In the US, in the case of environments such as manufacturing floors >>>> etc with horrific EMI levels, fiber is used instead of UTP CAT5/6. >>>> With EFI levels that high, even STP won't save you. >>> >>> STP can make things worse as almost nobody knows how to terminate >>> shields in such a way as to avoid ground loops. >> >> That's no longer true :-) >> >> And here it is a good article explaining the shielding advantadges: >> >> *** >> Why shielded twisted-pair matters for 10GBase-T >> http://www.cablinginstall.com/index/display/article-display/279393/articles/cabling-installation-maintenance/volume-14/issue-12/features/design/why-shielded-twisted-pair-matters-for-10gbase-t.html >> *** > > It's interesting to see them making a case for 10GbE over copper, > shielded or not, given that so few switches offer 10GbE RJ45 ports. I've > found exactly one, at $20K USD: > http://www.extremenetworks.com/products/summit-x650.aspx > > Everything else uses SPF ports for 10GbE.
I wonder if that really matters because most of these devices are modular. Anyway, there are more 10GBT switches out there: *** SMC8724-10BT TigerSwitch™ 10G http://www.smc.com/index.cfm?event=viewProduct&localeCode=EN_USA&cid=8&scid=107&pid=1646 New 8-Port 10GBASE-T Line Card for Cisco Catalyst 4900M Switch http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps6021/product_bulletin_c25-575166.html Industry's Highest Density Auto-Negotiating 10GBASE-T Switches http://www.aristanetworks.com/en/products/7100t *** And I suppose the rest of the big companies (like HP) also have a set of these devices in their portfolio. > Camaleón, you'll be hard pressed to win this debate of shielded vs > unshielded TP cable. Why not simply say you're happy with it and it > works for you. Because the bulk of the Western world used UTP > exclusively. And number don't lie. We invented both types here in the > US. And we only use UTP. If not UTP, we use fiber. That should be > informative, instructive. I wonder why any of my assertions can make you feel angry. They're just facts, not opinions... it's okay that UTP is the preferred method for USAnians, it is also the selected option for many companies in another countries but negating the advantadges of shielded LAN cables leads you nowhere. > Nobody has said you are wrong in any way for using STP, F/UTP. We > simply said it's unnecessary if the cable plant is installed correctly. > You already stated that cable installers there are less than properly > skilled. No, I did not say that. And I'll repeat: UTP cables can be installed by anyone, skilled or not, that's the problem. > I don't understand why you're being so defensive about this shielded > cable thing. Not defensive, just rebating your arguments on why should someone prefer the shielded cables. > I've never seen you act this way in a thread. I'm left assuming that > you personally selected S/F/UTP and did the install yourself, thus the > defensive stance. Of course I personally assumed that decision, I already said so. I would have gone crazy using UTP cabling here. It simply does not match for this kind of installation, I would have had to break the norms and the install couldn't have been certified. I guess is not that hard to understand. > If that's the case, simply say so, and we can move on. It's okay, Stan. I don't know why most of the replies in this list end this way with you. Greetings, -- Camaleón -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/jgmp32$g99$2...@dough.gmane.org
