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FireWire Goes Long Distance, Experimentally
P-Rod writes: "PC World.com News has an article detailing how Japanese researchers have created a low-cost way to send information through FireWire cables 100 meters at 400 Mbps. The current form of the Apple-created high-speed peripheral interface (known as the IEEE 1394 industry standard and dubbed i.Link by Sony) is limited to distances of 4.5 meters at that speed, its present top speed, unless a repeater device is used. This could bring new options to computer networking, especially considering FireWire's superb ease of use over Ethernet. "
Whats the advantage, besides speed, of using Firewire over Ethernet?
Last night I shot an elephant in my pajamas. How he got in my pajamas I'll never know.
The current form of the Apple-created high-speed peripheral interface (known as the IEEE 1394 industry standard and dubbed i.Link by Sony) is limited to distances of 4.5 meters at that speed, its present top speed, unless a repeater device is used. Oh fucking wonderful. Would some Japanese researchers care to tell me what I'm meant to do with the container-load of repeaters I just bought? I was gonna raise $6bn to cover the entire United states with a network of repeaters, placed in a grid of 4.5 meter squares. (Hey, they funded Iridium).
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How is firewire any easier to use than Ethernet? You plug the wire into the computer, and it works, doesn't it? Since most (all?) Macs have ethernet built in, and most PCs dont' have Firewire, it doesn't seem like it is that much difference. I assume that you have to enter your TCP/IP settings either way (or use DHCP).
How different is USB and Firewire in design from SCSI? On the face of it, they sound like very similar technologies, except that USB is built-in with less hassle. But I haven't checked it out in any detail, as is usually the case with me and most hardware I don't own (either one, as it happens).
;)
Also, I was wondering about those USB keyboards: do I really need to be typing that fast? Do you think Word can keep up, or would the paperclip get dizzy?
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I found the news of wireless firewire a lot more interesting.
:)
FW is really nice technology if everything falls in line - several meters at 200Mbps wireless, 400Mbps in long range cables and 800Mbps in "short" cabling. Cool..
sulka
"Although it is not true that all conservatives are stupid, it is true that most stupid people are conservative."
I don't really see how this would be any better for home networking than Ethernet. Your still going to have to setup the interface somehow, right? If your want to use a cablemodem to connect to the Internet your still going to have to use ethernet somewhere (well for the time being since AFAIK all cablemodems use an ethernet connection). I think that fast (and later gigabit) ethernet will satisfy the needs of home networks (and most corporate ones) for the foreseeable future.
;-> ) Well you get the idea it'd be cool, though I imagine the MPAA and the RIAA might want to start sueing people or charging royalties for these devices since they are of course opposed to any nifty technologies that make both general consumers and us geeks go "hey cool" ;->
The big potentional I see for firewire is networking regular consumer electronics with computers. Having sort of plug'n'play networking for things like your TV, VCR, DVD player, stereo etc... so that you could control them from your PC and move data between them easily, then that would be cool. Like caputing your home movies and vaction pictures onto your house server then being able to pull them off from any TV in the house, or being able to play MP3's from any stereo in the house all off of a central server, or taping Quake matches to your VCR (or hell just setting it for spectators to watch them live
Just my rambeling late night thoughts on what I'd like to be able to do with this kinda technology.
"Listen: We are here on Earth to fart around. Don't let anybody tell you any different!" - Kurt Vonnegut
Since the original article was sketchy of details, here's a link to the Japanese group that actually did it.
I know jack about cabling and plastics, but it says that they're using poly-methyl methacrylate wideband plastic optical fiber that's either Graded-Index (100m) or Multi-Layer (50m).
This also piqued my interest: "Perfluorinated POF has been successfully used in trials of 10 Gbps transmission. However, this POF is considered appropriate for office applications because it is only one-fifth the thickness of poly-methyl methacrylate POF. Expectations in the industry have grown for the potential of the easier-to-use poly-methyl methacrylate POF for digital home networks."
Could some engineering type explain all of this?
I understand a littany of off-topic posts, but WHAT ?
Suitability of anything over anything else requires a context.
"Staples found to be better than paper clips" - sure, maybe for holding paper together, but not for ejecting Mac floppies.
Firewire is nice for peripherals, but why must people compare it to ethernet? It's made to connect several devices *locally* in a high-speed fashion.
You're all mumbling crap about 63 devices blah blah blah and wondering about addressing schemes.
Is there a limitation that people don't know about regarding Ethernet MAC addresses?
Then, you talk about collisions.
Huh? Properly Vlanned and subnetted switched networks should be in place to deal with collisions.
Fibre Channel? First, it's 100 MBps, not 100mbps. Second, outside of external arrays on expensive-as-shit multiprocessor servers, when do you see it? You don't.
How many of the people complaining about SCSI actually know if it's the bus which is holding them up? Fine... it's nicer to run fiber from one rack to another than to get those damned SCSI cables routed around.
I think that most of the commenters are people who just get hard-ons when you mention fiber.
Firewire, Fast Ethernet, Ethernet, SCSI, Fibre Channel, USB, USB-II... when does it stop? How many devices shall we end up with that can't talk to one another? How many upgrades shall we have simply because we need new interfaces on them?
You know what we need? A cheaper solution. Why should SCSI cables cost so damned much? The adapters to plug your Fast SCSI-II drive into your U2W cable?
Keyword for success and unification is commodity . Which of the abovementioned standards is commodity? Ethernet/Fast Ethernet. RJ45 connectors? Cat5? Commodity.
Yeah, you're right though. Let's make it so there's no way in hell you can get what you need to get the new system on the network at 10 minutes after 8 in the evening. </rant>
-NevDull
I've seen a lot of comments about how FireWire is supposed to replace SCSI or Ethernet or USB. FireWire was meant to replace SCSI, it's not a network like Ethernet. However, it has a couple of advantages over SCSI. True Plug and Play. On a Power Macintosh one can insert a harddisk into the FireWire chain and it'll show up on the desktop, vice versa works as well. Scalability. The original spec is 400 Mbps, the 1394b spec is 800 Mbps and more is on the way. Also, a slower device using 400 Mbps on a 800 Mbps chain will NOT slow the whole bus down, as is the case with USB and SCSI. Easy. FireWire is appearing in all digital camcorders now and will be appearing in a lot more devices. Imagine your DVD player digitally connected up to your amp and a digital TV. These days, one can buy a 1299 dollar iMac with a 799 dollar camcorder and make movies out of the box that are far better than anything out there 4 years ago at any pricelevel below 20,000 dollars. Intel is pushing USB like crazy, but remember that USB needs a host. That's why Intel likes USB so much (and dislikes FireWire) since the PC (with Intel Pentium processor of course) will always be the center of things with USB. With FireWire devices can control each other without the need of a single host controlling devices. Not good for Intel, good for the consumer. Ethernet has it's place in the world, just like USB (slow hub based bus for keyboards and mice). FireWire will find it's own sweetspot. The reason PC users haven't seen it a lot is that Intel is not playing nice here, refusing to implement 1394 in their chipsets. Citing a lack of market for it. I guess Apple needs to create that market for them, just like they did with USB.
400 Mbps / 6,000,000,000 internet users. Sounds like the UUNET backbone :)
kwsNI
No hub is needed, making the network much easier to set up and more dynamic.
Self-configuring/bus mastering
High and guarrantied bandwidth for devices that are likely to take advantage of it (DV)
Interfaces directly with consumer peripherals (with FireWire ports).
Peripherals are equal 'citizens' to CPUs rather subservient to them
I think this last point in particular is a key point about FireWire in general that people often miss: devices can talk to each other over FireWire without the presence of a computer, which is why it is so attractive to manufacturers of consumer electronics who can use it for their own purposes and not simply to hook the device to a computer.
Using longwave tranceivers (1300 nm) FibreChannel can use cable lengths of up to 10 km with 1 Gbps data rate, and you'll start seeing 2 Gbps products real soon. These are't experimental products either, you can buy them now. FibreChannel can aslo use fabric switches to make networks considerable larger than anyone in their right mind would want to make.
The price can be a bit of a problem for a lot of applications right now, but if you need the bandwidth, expandability, and cable lengths, FibreChannel can provide them.
OK, I'm not going to give a full technical description here, but:
;-)
... you'll just have to type slower :-)
USB, PS/2, Serial Port, ADB (Apple Desktop Bus) are designed for low speed peripherals such as keyboards, modems or printers. USB does or will rule the roost here.
SCSI, IDE, Firewire are designed for higher speed devices such as hard disks. IDE is very limited (only really any good for internal hard disks), SCSI is (or was) superior to IDE in that it can support up to 7 periperals, longer cables and devices other than hard disks, but has cable termination and multiple version issues. Firewire is being touted as a replacement to SCSI, and will eventually be faster, but SCSI is still the choice for high perfomance if you can put up with its limitations.
Ethernet is designed for connecting computers (and printers) to each other in networks.
There is some overlap - in particular, Intel are pushing USB 2 as something to use instead of firewire. However, USB 2 is still vaporware, will be slower than Firewire, and has a lot of penalties stemming from its design as a relatively low speed protocol. USB 1 is also used for low speed storage like Zip disks.
So the comparison between USB and SCSI doesn't make an awful lot of sense - they are really designed for different things (unless you are talking about something like a Zip disk, in whch case SCSI will be higher performance if available).
Oh, and every computer I have ever bought has had SCSI built in and hasn't been any hassle, so what is buit in depends on what you buy
As for your keyboard, I doubt that Word can keep up with a USB keyboard
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My guess is that those 35% of Slashdot poll respondants were voting for `Garden Hose' because SCSI didn't appear on the list.
USB? Firewire? Yah, right! More than bandwidth than I can possibly use for a keyboard and mouse and not enough to make any sense at all for mass storage. Besides, I have worked damned hard to cut down on the proliferation of cables snaking across my desktop. Now Apple and some other folks are telling me I have to put them back. Only if someone comes up with a USB or Firewire hub that installs in an exposed, unused disk bay so that I don't have to have another piece of hardware sitting on the desk.
My performance tests, conducted last summer, indicated that performance was inversely proportional to the number of sprinkler heads you had attached to the bus but that the quality of the hose played some part in this (no hard data was collected on that aspect, though). Plus, adding devices to the bus required shutting down the network as the garden hose bus architecture closely resembles a Thinwire Ethernet. There are some garden hose hubs but they usually only come in two-port models and still require that you shut down an entire leg of the network in order to attach devices.
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CUR ALLOC 20195.....5804M
I don't know what else you are looking for, but in general, glass has better transmission qualities than plastic. That is, at the wavelengths that diodes currently run best(IR and red) the signal can travel through more glass before being lost to diffusion and noise.
The main disadvantages for glass are cost and flexibility. To some unknowing home user who is used to coiling cables around his finger, leaving loops in cable runs that are converted to kinks when someone pulls on them, yanking speaker wire around the sharp corners of furniture and so forth, glass would be bad. Even really thin and surprisingly flexible glass will break when you bend it too sharply. Plastic doesn't have this problem. There is still signal loss around curves, but that happens to both glass and plastic when the curves start getting sharp.
If you are wondering about Graded Index or Multi-Layer, then we are talking about the Index of Refraction of the plastic or glass medium. Graded Index has a continuous variation in IoR from the center to the edge. The idea being that if the light starts to stray from the center of the fiber(as occurs when the fiber is bent), it will be bent(refracted) back toward the center. The Multi-Layer form does the same thing but with sharp, discrete boundaries between the layers with differing IoR. This causes a reflection rather than a gradual refraction. Typically the layers are set up to reduce the loss because with each reflection some of the light is not reflected. If you've ever heard of "multi-coated" optics on binoculars or telescopes, then we are toalking about the same thing. The idea is to minimize the loss due to reflection that happens whenever the light meets a boundary between media with different IoR. The Multi-Layer is trying to emulate the gradient. The difference as far as the light is concerned(whether a given setup appears to be a gradient or sharp boundary) depends on the wavelength, the delta of the IoR, the delta rate of the the IoR between multiple layers, and thickness of each layer. IOW, as you make more layers and the layers get thinner and the IoR delta between each gets smaller, multi-layer -> gradient. The gradient is ideal, but as usual harder(AKA more expensive) to build and build well. A typical gradient fiber will start out as a multi-layer that then gets "treated" with heat or whatever to cause the layers to melt or diffuse into each other. IF all goes well, the discrete layers turn into a smooth gradient. This kind of process works for both glass and plastic although much less effort is spent on making "good" plastic since generally "poor" glass beats it over distance anyway. For short length multi mode fiber, plastic can and does compete. For long hops, single mode glass is the only way to go.
Now that fiber is making its way into the more hostile and cost sensitive environment of untrained home users with generally short hops, plastic's toughness and low cost will probably win over glass.
Good judgement comes from experience, and experience comes from bad judgement.
- W. Wriston, former Citibank CEO
I thought that Apple designed and patented the *connectors* that are used in the Firewire specification, but only *participated* in the working group consisting of a number of companies (Sony, Phillips, Yamaha, etc) that actually invented the Firewire spec.
...
In other words, its incorrect to say that Apple invented Firewire... but they did invent the *connectors*.
Could someone with a better working knowledge of how the IEEE-1394 spec was presented clear this up? Or, point me in the direction of details about where this technology actually came from
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
FireWire is NOT A BUS PROTOCOL. FireWire is a SERIAL protocol. A bus transmits multiple bits at the same time, a serial connection transmits one bit at a time. FireWire sends one bit at a time, hence its speed measured in megabits per second. A FW-Ethernet converter would be stupid, Ethernet is only 100Mbps and interpreting the FW protocol and translating it to your favourite Ethernet protocol would take time which increases lag.
I'm a loner Dottie, a Rebel.
I think long distance FireWire would be cool but I'm bothered by the people wanting to use it to watch television or DVDs. Want to know a simple way to watch TV from the DVD downstairs? Run a coax from the DVD to your TV. Get a radio remote to control it. Sheesh. I think this would be great for device networking in data centers. You could get SCSI speeds over really long distances, need more speed? Just add more FW ports. I really think that FW has the potential to replace IEEE 802.x in many environments, especially as the protocol stands now. It would be much simpler to treat any networked device as a remote device on the network. The autonegotiation would go over really well for the non-networking engineers setting up a LAN in their house. Besides the auto-setup all the routing and such is done in the hardware so the software and CPU are totally free to do other things, this is a good thing when executing a large/complex remote file.
I'm a loner Dottie, a Rebel.
Sorry, but that's a stupid statement. You can not replace 1394 or Ethernet with optical lines because you'd need some standard specifying the physical connections and the protocol to be run over those.
Guess which standards there are? You can do Ethernet over optical lines (until recently the only way to get Gigabit-Ethernet) and the 1394.b standard is also supposed to specify optical connections allowing 3.2 Gbit/s over 100m lengths (and 3.2 Gbit/s over 4.5m shielded electrical cable).
Guess I was too lazy when I posted that earlier today... so thanks for doing my web browsing for me.
And I guess I'll also just go get my question ("Is the 4-wire adapter compatible with the 6-wire one, and are there convertors so I can use the i.link port on my Sony laptop?") answered when I have some free time to read the IEEE1394 trade association web site...
:)
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --