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Ethernet at 10 Gbps
An anonymous reader writes "This article talks about 10 Gigabit Ethernet and asks, 'But just how much data can a person consume?' Currently at work, we're working on a major project to re-architect our core application platform so that the different systems can be de-coupled and hosted separately. The legacy design implicitly relies on systems being in the same LAN due to bandwidth-expensive operations (e.g., database replication). Having this much bandwidth would change the way we design. What would you do with this much bandwidth?"
As a CCIE, I have been designing networks for years. I have analyzed traffic to/from desktops and watched traffic to the average desktop never even get above 27mbps. This is due to the average file size of the transfer which is rarely above 10 megabytes. At 10 megs, it only takes a few seconds to get it transfered and it only has a few seconds to get up to speed, by the time it gets all revved up, the file transfer is complete.
High-end workstations such as CAD with gigabit connections, working with 500 mb files, or multi-gigabit video files will occasionally reach 500 to 600 mbps, and even then only for a couple of seconds. At these speeds, power users can use that network connection as if it were a local drive, because at those speeds you are matching the speed at which you're reading/writing data to your local hard drive.
The only time I've ever seen near gigabit traffic at a steady pace was at network servers, where traffic can reach a steady 600mbps on a single gig link - which is maxing out the speed at which the server drive can read/write data to its hard drive. Think of it this way, a 1 gigaBIT link can transfer a 1 gigaBYTE file in about 10 seconds, that's FAST! Conversely, it takes nearly 20-30 seconds just to write that large a file to the hard drive.
Now, on a Cisco 6500 core switch, or a Cisco GSR 12000 where traffic is aggregated, these are the only places where I've actually seen multi-gigabit traffic rates, and that was across the switch fabric - not all directed to a single interface.
The 12000 GSR already has a 10gb interface, it is a single line card that takes up a full slot. It sells for about $60,000 and is used to move data from the switch fabric of one GSR to another GSR, which means you need to put in 2 of them at a mere $120,000 to get the two connected.
Moving to optical links, you can get up to 36Gbps using Dense Wavelength Division Multiplexing on multimode fiber. This uses several colors of laser light to transmit multiple 'channels' across a single fiber link.
Even at these tremendous speeds, they are only used at traffic aggregation points, again because any network device, even a turbocharged SAN couldn't handle reading/writing at those speeds for anything longer than a quick burst.
I say this: If you think that 10gig/sec is your answer, you're looking at the wrong problem. You can get the performance you need at gigabit rates.
I'm not saying that we'll never need 10gigabit to the desktop, just not until we solve the hard drive bottleneck. Solid state storage could solve the problem, but we'd need to have solid state drives that store 100gb of data in order to match the throughput of the network.
Good security is based upon reality and common sense. Common sense is a function of having common knowledge.
This much bandwidth isn't going to help you do any of these things. I upgraded my network to gigabit ethernet about a year ago (from 100 mbit), and much to my surprise, the speed increase was only about 3 times when copying files from one machine to another. I did a little math, and found the answer. Your average ATA hard drive, even at max bus speed, only delivers 0.8 Gbps. And in the real world, you are lucky to get half that from a single drive. In my own test transfers from RAID1 and RAID5 arrays, my transfer rates never once exceeded 0.70 Gbps. Until there is a fundamental increase in the amount of data you can get off a spinning disc, its not likely that a home user is going to saturate a 1 Gbps line, much less a 10 Gbps line.