Slashdot Mirror
Corporate Data Centers As Ethernet's Next Frontier
alphadogg writes with a story that's about the possibilities for the next generation(s) of Ethernet, stuff far beyond 10base-T: "Ethernet has conquered much of the network world and is now headed deep into the data center to handle everything from storage to LAN to high-performance computing applications. Cisco, IBM and other big names are behind standards efforts, and while there is some dispute over exactly what to call this technology, vendors seem to be moving ahead with it, and it's already showing up in pre-standard products. 'I don't see any show-stoppers here — it's just time,' says one network equipment-maker rep. 'This is just another evolutionary step. Ethernet worked great for mundane or typical applications — now we're getting to time-sensitive applications and we need to have a little bit more congestion control in there.'"
FTA: "But in its current state, Ethernet is not optimized to provide the service required for storage and high-performance computing traffic -- speed alone won't cut it, vendors say. Ethernet, which drops packets when traffic congestion occurs, needs to evolve into a low latency, "lossless" transport technology with congestion management and flow control features, CEE and DCE backers say."
If I understand right, they're trying to change Ethernet because of TCP/IP? Isn't that kinda, backwards as a concept?
"Ethernet has conquered much of the network world and is now headed deep into the data center to handle everything from storage to LAN to high-performance computing applications."
Ethernet? Used for LAN? Jeepers, who'd ever have though of using Ethernet for THAT! I bet it'll be much faster than my 300-baud modem! And we can even connect storage devices to it!
And to make it easy we could call it "TokenRing".
Or maybe a token passing bus! Maybe call it "ARCnet".
Seriously, if there are problems with Ethernet ... for the usage you envision ... don't try to change Ethernet.
You take the parts you want from Ethernet and you create a NEW standard with the other features you want.
But you leave Ethernet as Ethernet. That way there is no confusion.
This seems like a total kludge being put together by networking equipment vendors to find a way to differentiate their products and return to the days where a 10 Base-T hub was $1000.
Network gear is now mostly a commodity, except at the super high end.
The vendors hate that - so they are trying to push the host's functionality into the LAN gear instead. They don't want to provide "dumb pipes" any longer, they want to monkey around with the traffic and protocols, and provide virtual servers and such in their boxes.
Really, it's just an attempt to make the servers the commodity and their gear the expensive part.
Except... you already can implement this yourself with existing equipment and software, with much better control and no vendor lock-in. For low-end solutions, a Linux cluster works great behind an UltraMonkey front end. For higher-end ones, well, that's what IBM z-series mainframes are for.
What a great solution in search of a problem.
From the article:
"Ethernet is not optimized to provide the service required for storage and high-performance computing traffic -- speed alone won't cut it, vendors say. Ethernet, which drops packets when traffic congestion occurs, needs to evolve into a low latency, "lossless" transport technology with congestion management and flow control"
Q: Packet loss and traffic congestion are to Ethernet as:
A) blue screens are to Windows
B) registers are to assembly
C) mustard is to sausages
"Creationists make it sound as though a 'theory' is something you dreamt up after being drunk all night." -Asimov
There's a draft of Firewire that hasn't hit yet that uses standard Ethernet cables. The port is supposed to be able to use either Firewire OR Ethernet and be able to switch between them depending on what it's plugged into. This sounds ideal to me.
The preceding post was not a Slashvertisement.
Ethernet is more of a generic name than a specific thing. It's more like "soup" than it is like "VHS".
Ethernet started as a daisy-chained garden-hose-size coax cable with vampire taps. Then RG-58 with BNC connectors, then twisted pairs to a hub, then switching hubs, then wireless... Not much stayed the same, not speed, media, topology,... except maybe carrier-sense. It's basically a comforting name, with the Ethernet-of-the-day varying at the chef's whim.
Keeping the name while tossing out the last remaining bit of commonality is a bit bizarre.
Fibre Channel over Ethernet has real promise, but these new requirements are a real stumbling block.
What many of the posters here may not realize is that storage traffic (and the "standard" SCSI it uses) is extremely intolerant of dropped frames. A link that in the TCP/IP world would be specatacular is wholly unsuited for block-level storage, which is too latency sensitive to have time to recover from dropped data.
Since the most common cause of dropped frames within a data center is congestion, FCoE requires your Ethernet to implement frame-based flow control, which prevents the congestion from occuring, along with the resulting frame loss.
SirWired
Ethernet already has flow control at the link-level - they're called stop frames (and since all modern switches give you dedicated links to end workstations and have some amount of hardware buffering, collisions/overrun aren't an issue). Now, since the world really runs on IP (doing raw ethernet would only ever work in the most local of LAN applications which is rather pointless in most deployments), and IP has TOS bits (which every real modern router can classify, queue, and throttle per-queue all in the hardware fast-path with no additional latency), I'm failing to see what they're proposing to solve since the problem is already solved. 1G/10G switches are used all over data centers and in HPC situations today (and have been for years)...
Nope, the CSMA/CA part of Ethernet is gone also. Specs for a GigE hub exist in the standards, but nobody ever implemented them. (Switching got to be too cheap for anybody to bother.)
Obviously it didn't even get specc'd out with 10Gb Ethernet.
Oh, the frame format is still more-or-less the same from Classic Ethernet. Not identical, but still pretty close.
SirWired
Are there any foreseeable applications for the consumer world?
Connect your new keyboard and mouse via ethernet.
Connect your new HDD* via ethernet.
Connect your new video card via ethernet.
Connect your new scanner via ethernet.
Connect your new CD/DVD/BR via ethernet.
Connect your new printer* via ethernet.
Connect your new webcam* via ethernet.
No more USB cables with a million different connector types. No more PATA or SATA cables. No more serial or parallel cables. No more trying to figure out where to plug a given device in on a motherboard or looking for spare PCI/whatever slots - Just one type of cable and they all plug into a switch-like section of the motherboard.
Now, some devices (video cards as the most obvious) will still require extra power, but most devices could probably manage with a variant on PoE, meaning the inside of your case goes from rats-nets of assorted cable types, to a half-dozen or so tidy round cables.
* Yes, you can already get network enabled versions of these, but they count as a real full-fledged network endpoint, not as a slave device "local" to a particular computer.
You realise "no more different connector types" was the reasoning with USB?
Extreme Programming - Redundant Array of Inexpensive Developers
Given the direction SATA & USB is going, the rate at which its bandwidth has increased relative to traditional CATx ethernet, and the relatively lower cost of interconnection devices, is Ethernet really the best? If we're going to making significant wiring changes in server rooms I'd prefer to just do it once and standardize on the cheapest, fastest "2-wire" solution that makes sense.
And sadly, you'd see the same issues it with this standard too, because an ethernet RJ-45 plug isn't appropriate to plug into a cell phone, digital camera or mp3 player, but a 5-pin mini-connector isn't appropriate to run 25 feet to a switch/router either.
Ohh.... That hurts my brain on so many levels. "...directional markings are provided for optimum signal transfer." Wouldn't want the electrons to forget which way they were supposed to go, eh?
Jeremy http://alucinari.net
I think the biggest reason that there are hundreds of different USB connectors is that standardized plugs don't help sell 30 dollar Apple or Sony branded AC/DC adapters.
I really loved my old motorola phone with the mini-usb connector, now my LG phone doesn't share it's connector with any other device I own.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
* Yes, you can already get network enabled versions of these, but they count as a real full-fledged network endpoint, not as a slave device "local" to a particular computer.
You can with protocols like iSCSI or ATAoE. A lot of enterprise gear uses iSCSI, which makes a remote device appear like a local SCSI device, and some consumer-grade NAS devices running Linux can act as ATAoE devices, which does the same thing but with ATA instead of SCSI and over raw Ethernet frames rather than over IP.
I am TheRaven on Soylent News
It sounds like they just want bandwidth reservation and isochronous transfers on Ethernet. Something that would establish a virtual circuit and then not drop frames. Something with an Asynchronous Transfer Mode, perhaps?
I am TheRaven on Soylent News
You probably don't have a storage area network, running over some proprietary fiber protocol, or some hight performance proprietary cluster, or a supercomputer around, do you? All those things are fading out as Ethernet evolves to do those kinds of jobs, but they didn't disapear yet.
Rethinking email
Why is having the tab on the bottom better?
Chernobyl 'not a wildlife haven' - BBC News
Quite a few of the non-standard USB leads use non-standard connectors because they're actually USB-serial converters, not just leads. My previous phone, a Sony Ericsson, was like that.
Chernobyl 'not a wildlife haven' - BBC News
Ethernet has nothing to do with the connector type. It is a layer 2 protocol that sits on top of the physical transport medium. There is a little bit of overlap with things like wiring specs for distances and attenuation, but it ethernet itself doesn't really care what plugs or wires you use. even if connectors were in the spect, it would still likely be extended to allow for new connector types to fit the appropriate devices (mobile phones, mp3 players, etc).
thus, for the consumer world you probably wouldn't see much difference on the user end. developers, on the other hand, would have to start pushing their device drivers into the network stack in order to get them working. say hello to firewalls and IDS/IPS on your HDD and video card.
check out my comic: Essential Tremors
Nope, both of which have higher overhead than full-duplex ethernet. They have better throughput than half-duplex ethernet, which is about as useful as being better than avian carriers. Half-duplex ethernet should just be banned entirely. Maybe that would make Linksys wake up.
Half-duplex ethernet corresponds to the way things work on a shared peer-to-peer radio channel. Like WiFi. (Which uses the Ethernet MAC and collision/backoff algorithms - though I think the collision detection is inferred rather than explicit.) (WiMAX, however, is a full-duplex protocol with central stations monopolizing an outbound channel and assigning timeslots for replies from remote stations on an inbound channel.)
Of course that DOES qualify as an "avian carrier", doesn't it?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Actually Not at all.
The design of RJacks specifically RJ-45, try and mitgate this as much as possible.
If its properly crimped, wiggling the cable, even pulling it should have no effect on either the cable contact or the jack contact.
i.e. it has no importance in real life by design.