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Ethernet Over Assorted Materials
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."
I think it is just short of a mile, thus the technology is nothing more than hype. It is the last 20 miles that need to be addressed not the last 5000 ft.
Got Code?
Hey, I just went out and bought a spool of barbed wire, only to discover that Cisco hasn't yet developed Ethernet-over-barbed-wire technology.
I guess I'll just have to reattach the alligator clips for my Ethernet-over-city-sewer connection.
That's "Mr. Soulless Automaton" to you, Bub.
"By offering Ethernet-like speeds over regular phone wire, at reaches up to 5,000 feet, and co-existing with phone traffic, LRE brings rich, advanced services such as next generation video-on-demand to places it has not gone before."
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.
Cisco spokesperson "Hugh Barrass"? Yeah, wait for the Ethernet-over-Jell-O(tm) Puddin' Pops protocol called "IP Freely"...
Carousel is a lie!
Sure, it's faster than DSL, but it's only good to 5000 feet - the last MILE for sure. Great in buildings, dorms, hospitals, etc. For us poor slobs that are 18,000+ feet of copper away from their CO, we're still stuck with lame alternatives. When are we going to see something that solves the DISTANCE problem, not the SPEED one?
"I feel that if a person can't communicate, the very least he can do is to shut up." -- Tom Lehrer
Ummm.... actually I'm willing to bet that you do have at least Cat1 cabling in your building. Unless you don't have a phone line at all, Cat3 has been the standard cable used for regular phone lines in homes for quite a few years now. So their gist is that they can get high-speed data off regular phone lines.
It actually works pretty well. We use it on a large government facility that has some really old wiring in buildings that we don't have fiber runs into.
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.
Casca
If you follow the link to Cisco's site, there is a link on the right for the video presentation.
I do not deploy Linux. Ever.
...or BWoE. I suspect there would be a number of spikes in the connection.
Bill Clinton: Pimp we can believe in. - The Shirt!!!
Okay. So, yeah, we might finally have a reasonable technology to solve the "last mile" problem.
:)
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
Barclay family motto:
Aut agere aut mori.
(Either action or death.)
I do not believe Cisco does, or ever has, positioned LRE as a "last-mile" technology. LRE is more about leveraging existing cabling infrastucture in a multi-unit facilities such as hotels and hospitals.
Cisco's LRE product offering requires two pieces:
1. An LRE-capable switch at the head-end (such as a 2900XL LRE), 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 at the head-end and hand off to the PBX before bringing everything in to the 2900XL LRE.
2. Cisco 575 CPE, 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 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.
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).
We are using LRE technology to connect approximately 50 buildings via cat 1 and cat 3 underground phone cable. LRE requires only a signle pair, and can share a pair with a voice line, just like DSL.
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
It was only 1Mb/s, but it could communicate over ANYTHING. Would not take too much to bump the speed up with todays technology.
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).
Feed the need: Digitaladdiction.net
Where will the bandwidth come from?
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.
I saw the demo for this last year, its pretty lame. If you can, grab the demo kit from the marketing slime and try it with regular 10bT ethernet and it still works.
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
Hemos is like...sci-fi fans;he thinks technology is cool, but he hasn't bothered to understand the science it's based on
I do this for a living, so I know. At the top of the food chain is the SONET/SDH telecommunications network. That works at between OC12 (660 Mbit/s) and OC768 (40+Gb/s) rates, and go typical distances of a hundred kilometers (upto a thousand). And these rates can be done many times on difference frequencies of light (DWDM) on a single fibers; and you can have multiple fibers between offices as well.
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.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"