[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [K12OSN] Gigabit on cat5 and even cat3!



Actually, the Gig-E spec for twisted pair (IEEE 802.3ab) always has specified Cat 5. You are quite correct in saying that you don't need Cat 5e. However, there's no way you'll get it working across Cat 3 at full Gig-E speeds, if at all. You'd be lucky to get 20Mbps across it, assuming it even works! Even if it does somehow sync up across Cat 3, you'll have so many CRC errors it's crazy; you're much better off simply upgrading your cable plant, even given what it costs. We've had to do exactly that to a bunch of our schools, 'cause even 100BaseTX just will not work across Cat 3 (100BaseT4 will, but nobody makes those anymore).

If someone's figured out how to actually pull off Gig-E across *Cat 3*, then it's totally nonstandard and violates every IEEE spec that exists. You actually *saw* this running on Cat 3 at *full* 1Gbps? If so, what were they using for a data xfer demonstration? A FTP session? A Windows "drag 'n' drop" file copy? Pardon me if I seem a bit cynical, but I just have a very hard time believing IEEE 802.3ab Gig-E on Cat 3 of *any* cable length.

--TP

Richard K. Ingalls wrote:

Just wanted to share:

I learned at the International Academy of Science last week that there is a company that makes NICs and Switches that allow 100% Gigabit Ethernet speeds on existing cat5 & cat3 cables (not just cat5e). That means we can upgrade to Gigabit backbones without rewiring! Just buy new switches and new NICs for the servers and you're done. Very cool! I couldn't believe it when I saw them plug in cat3 cables and make it run at Gigabit speed (100%)!!!!! Whoa.

I thought that I ought to become a reseller of these things. I haven't, of course, cuz' I make so much money as a tech. coord. at my small rural school (LOL) - I don't need another job. I definately wouldn't have the time for it.

Anyway, for those of you running K12LTSP and using or thinking about using Gigabit - you don't have to spend $250.000 on rewiring! The company is called wideband (i think: www.wband.com).


--
------------------------------------------------------------------------
Do you Slack!?
Slackware GNU/Linux <http://www.slackware.com/> - Clean, secure, and just works.





[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]