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Ethernet Over Assorted Materials
Posted by
timothy
on Thu Jan 03, 2002 05:38 PM
from the as-long-as-the-bits-are-bits dept.
from the as-long-as-the-bits-are-bits dept.
saridder writes: "Cisco has demonstrated their latest last mile technology,
and not only can you now have 10 MB Ethernet over Cat3, Cat2, Cat1, try lamp
power cord, battery jumper terminals, barbed wire, etc. This may have solved the last mile problem, and at 10 MB, it blows DSL out of the water."
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Ethernet Over Assorted Materials
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5000 ft != MILE (Score:5, Insightful)
Strange for of dyslexia? (Score:3, Funny)
This solves nothing (Score:3, Insightful)
The problem is money. Nobody wants to spend the dollars necessary to hook us all up with data cable. That's why all the hullabalo about cable ISPs and DSL--they both utilize an existing physical connection.
In other words, the answer will not come from Cisco, it will come from somebody with deep pockets. And the only pockets deep enough in this case belong to the federal government.
Re:This solves nothing (Score:5, Insightful)
Barbed wire? (Score:5, Funny)
I guess I'll just have to reattach the alligator clips for my Ethernet-over-city-sewer connection.
Re:Barbed wire? (Score:4, Informative)
I had lunch with a Cisco sales rep, and apparently thier demo for this stuff includes several feet of barb wire. They unhook it, and re hook it up, to prove its working.
The demo starts out with like 1000 feet of Cat 3, then cat 1, then lamp cable, then the barb wire, then more cable, reavaling each section as they talk about it to wow you. I haven't seen it, the sales guy just told me about it.
Sounds pretty interesting... it says 10 Mbps at 5000 feet... I assume you get less Mbps the farther you go out... actaully the sales rep was supposed to get me this info, and never did... I'll get on his back about it....
-Tripp
Re:Saw the demo (Score:5, Informative)
They have built a big wooden frame, about 1.2 metres on a side. Across the front of it they have a number of strips of cloth, held in place with velcro. The spiel starts about putting a signal down cat5 cable, and how expensive that can be. The rep pulls off the top strip of cloth, revealing some cat5 running between two RJ45 plugs, at the top is a connection to a LRE switch, and coming out of the bottom still hidden by 4 or 5 more strips of cloth is another RJ45 going to another LRE switch with a signal light. The rep makes a point to plug and unplug the cat5 to show the signal lights going on and off.
Then the pitch starts talking about cheaper cable, and then he pulls off the next strip, showing cat3 phone cable. The jumper from the cat5 RJ45 goes into the RJ45 for the cat3, and the jumper on the other side goes down to the next level which is still hidden.
Soon the pitch talks about pushing signal over anything, and the sales rep pulls off the next cloth, revealing two strips of lamp cord. And finally the bottom strip reveals four strands of barbed wire between 4 insulator posts, with RJ45 connectors at either end. BFD.
The final result is that the LRE signal is running over a bunch of impedence mismatched wires for a total distance of about 5 metres. If the rep is doing this canned demo in a conference room and there is 10bT available, try running a regular 10bT signal through this frame, it will probably still work.
They may also have a 200-250 metre spool of twisted pair phone wire with RJ45s at either end. That is impressive, since 10bT will have lots of error at such a distance, but LongReachEthernet will back down to about 2 Mbps and still function.
And this isn't a direct plug replacement for ethernet, LRE requires both dedicated blades in their switches for distribution, and very expensive receiving units for the far end. They are targetting places with old wiring going to a wiring closet, they can't actually compete with DSL at this time. But there is always a question about using these switches for neighborhood distibution when a telco has a small remote switch serving customers at the end of a fibre loop. The rep will not make any committment to that.
the AC
It's distance-limited.... (Score:5, Insightful)
So, once again, 90% of the population is too far from the CO for this to bring broadband into the home.
The problem isn't the last mile, contrary to the buzzwords... the problem is getting the pipe to run many, many miles to actual end users' homes.
Sigh... (Score:4, Funny)
Still only useful for 5K feet (Score:4, Interesting)
We use it (Score:5, Interesting)
Has anyone heard the Cisco story about ethernet over barbed wire? Our salesrep tells a story about a facility in Kuwait (I think) that was having a terrible time keeping a link up between two buildings. The locals kept stealing the cable they were using for the valuable copper. They ended up getting ethernet to run over a piece of barbed wire running between the buildings. The error rate was high, and the sustainable throughput was abismal, but with TCP's error correction they were able to get a useful connection through.
I don't know how true that really is, might be a Cisco myth told to impress customers or something.
Short on Detail? (Score:3, Interesting)
Anyway, it seems like a good idea, however, is there another block here that can be achieved by a company (ie the bells last mile influence on dsl)? Broadband to the masses ideas seem to come and go with the wind lately, and most seem never to pan out.
Yes, ethernet over barbed wire. Big deal. (Score:5, Interesting)
If you follow the link to Cisco's site, there is a link on the right for the video presentation.
Barbed wire over ethernet (Score:4, Funny)
Riiight ... and where will the bandwidth come from (Score:5, Informative)
But where the *hell* is all this bandwidth going to come from? I mean, server bandwidth is expensive. I know a few people who donate Debian mirrors, and it costs them a pretty penny, that's for sure.
I mean, I'd still want to have this; if for nothing more than great community networks. (Community as in physical locality)
But this won't solve all our problems, it will probably bring us new ones.
Not that we still shouldn't do it
Re:Riiight ... and where will the bandwidth come f (Score:5, Funny)
Me.
If I had a 10MB connection to my house, I'd mirror shit just to mirror it. I'd download kernels and patches, and tell the maintainers to put me on the list of mirrors. And I wouldn't be alone.
That's one of the reasons that P2P networks work so well. There are so many nodes to get the information from.
Server bandwidth is expensive because it is a scarce commodity. How much do you pay per month for the 100MB connection between your workstation and your server? If you (conveniently) don't count the cost of the infrastructure, the price is zero. Factor in the cost of the infrastructure, and amortize it over the life of the equipment and that number is still ridiculously low. ($70 for two NICs, $80 for a half-decent switch (optional), say it's only good for a year. That's $12.50 a month!)
Server bandwidth is expensive because servers are concentrated into little high traffic nodes. Spread the traffic out (ala freenet, gnutella, morpheus, etc.) and costs drop dramatically. Make bandwidth a commodity, and you will start paying commodity prices.
Re:Riiight ... and where will the bandwidth come f (Score:5, Informative)
At present, 6.4 Terabits can be shifted on a single fiber, although I don't think that has been deployed in any serious way, ~100Gb/s or so are much more common. If you need more bandwidth, add another wavelength (cost: a millionish); or if the fiber is full (rare right now, but will happen more and more often in a few years or a decade), then you need to lay new fibers- that costs 100s of millions; but we are talking significant bandwidth from that- you don't lay 1 fiber you lay 50 or so and keep most of them for expansion or sell them to other telecoms companies to pay for your layout.
LRE (Score:5, Informative)
Cisco's LRE product offering requires two pieces:
1. An LRE-capable switch at the head-end (such as a 2900XL LRE [cisco.com]), which terminates the LRE and has a standard Ethernet handoff to your normal data equipment. In an intergrated voice/data setup (where you're reusing existing voice cabling to carry voice AND data) you would then use their LRE 48 POTS Splitter [cisco.com] at the head-end and hand off to the PBX before bringing everything in to the 2900XL LRE.
2. Cisco 575 CPE [cisco.com], which uplinks to the head-end and splits off the voice and the data. Very similar to Cisco's 600 series.
Sound like DSL? It essentially is, just on a smaller scale (3500XL/2900XL LRE costs a whole hell of a lot less then a carrier-class DSLAM). In fact, scanning over the Cisco 575 CPE Overview [cisco.com], Cisco declares the technology to be "based on VDSL".
Draw your own conclusions, but I have never heard this positioned as a last-mile replacement. The article never seems to hint at it either, but simply reiterate their marketing the product line for multi-tenant facilities.
More info here (Score:3, Informative)
Hats off to Cisco's engineers for putting this into hardware - with the emerging IEEE standard, hopefully there will be others.
What about RFI? (Score:3, Interesting)
The nice 10 MHz square waves going over an unshielded wire are going to make a whole lot of harmonics (and products) all up and down the radio spectrum. Depending on the power you'd need to push your signal down a mile of barbed wire (and with a transmitting antenna a mile long), I'm pretty sure you'd run afoul of any number of FCC regs. Plus, it would probably just irritate the cows :-).
Re:What about RFI? (Score:5, Informative)
If this is really VDSL-based, there will be several modulated sine waves in use.
Depending on the power you'd need to push your signal down a mile of barbed wire
Easily determined by the required bitrate, available bandwidth, and noise floor. Millivolts, although they'll probably use a couple volts (like standard 10/100/1000baseT) to make the parts cheaper.
with a transmitting antenna a mile long
Properly-designed transmission line does not radiate (much). This is primarily done by either running a balanced signal down two twisted conductors (twisted pair) or running an unbalanced signal inside a grounded shield (coax).
What about DSDN? (Score:3, Interesting)
I hate to sound like I'm marketing it, but what about DSDN? It's true that it doesn't run over existing technologies, but for 10 Mbps Internet access it's considerably cheaper than the current alternatives (such as direct fibre-optic lines) and is supposed to cost about as much for the end user as their cable or DSL ISP already does.
It's already in use in Denver as well as a section of Utah, and it's supposed to be very fast in practice - not just theory. The Denver ISP has a site at wideopenwest.com [wideopenwest.com] and the company that designed the technology is at switchpoint.com [switchpoint.com]. Switchpoint is the one testing it in Utah as far as I know.
I also know that Slashdot has mentioned this tech before, but it bears repeating this for others; we'll never get past sub-standard cable and phoneline solutions if people don't demand alternatives.
LRE is not vapor, it works quite well (Score:5, Interesting)
Out to 3000 feet 15 megabits is normal, between 3000 and 5000 only 5 megabits is typical, but it depends on the quality of the cable.
This technology is based on VDSL and works using the same principals, but runs at a higher data rate, limiting the distance. Also, LRE transports Ethernet frames directly, without any ATM protocol overhead, unlike most of the other DSL solutions. This greatly reduces costs.
The Cisco 575 LRE device is much like the low-end Cisco 600 series DSL routers in appearance, but has no active layer 3 capabilities. Basically, the remote 575 port appears to the 2924LRE as if it were a local port, allowing trunking and vlan assignments as supported by the 2900 series switch.
If you could order a number of "alarm pairs(dry copper)" from your local telco, between a friendly ISP and your houses, and the distance was less than 5000 ft., this would be a pretty economical solution. Otherwise, it's not of much use for the average homeowner.
-Falcor
Uhm, ARCNET? (Score:4, Insightful)
This isn't new or suprising. This technology has been around for years. God, I remember using ARCNET to communicate thru barbed wire back in 1995 (as a test to prove it could).
Fiber-Optics Over Fishing Line (FOOFL) (Score:3, Funny)
Someone needs to convert pound-test to bandwidth, and there you go.
Which company? (Score:3, Funny)
Audio cable good coax replacement.... (Score:3, Interesting)
My Connection... (Score:3, Funny)
"Oh yeah?! I've got a barbed wire Ethernet line!"
"A what?!"
"A barbed-wire Ethernet line. Haven't you heard of that?"
"Umm... No, I can't say I have."
"Oh... ACME Networks installed it for me last month. It cost a fortune, because there are no barbed wire fences around where I live, so they had to upgrade their entire barbed wire infrastructure; they billed me for like 20 miles of barbed wire fencing."
Did anyone read the article? (Score:3, Insightful)
Cisco's LRE is a LAN technology. This doesn't have one rat fart to do with any part of the last mile. It works over existing Cat1-3 (phone) premise wiring for distances of up to 5000ft. This is not a replacement for Cable Modems, DSL, or ougie boards. And no, it does not "blow DSL out of the water." If you are within 5000ft of a CO, you can get very good DSL rates over ONE (30AWG) pair (not the 4pairs that comprise CatX cables.)
This is technology for multi-tenate units like apartment buildings, hotels, offices, malls, etc. The article spells this out in perfectly plain engligh:
- Owners of multi-unit buildings such as hotels, apartments buildings, business complexes, universities, hospitals, manufacturing floors and government agencies are now able to deliver an unprecedented number and a variety of new, broadband applications to users.
You will not see this being run through the public telephone grid.There actually is an IEEE standards body for "Ethernet in the Last Mile" -- I don't know the number for it off hand. And companies are designing hardware to provide 10M ethernet connections with further reach than SDSL. And this is last mile technology. (I'm too far from the CO in any case.)
Re:Obviously a Hoax (Score:3, Informative)