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Marvell’s SheevaPlug

Two years ago, I discovered PowerLine networking and have used it ever since, first to cover a CAT5E “dead spot” in my Colorado house, and more recently to finesse Wi-Fi outages at Carol’s sister’s house. The Linksys PLE200 Ethernet bridges work fantastically well within our house, and have sufficient bandwidth to stream HD video. With one unit near my router downstairs, I can take the other unit and plug in to the Internet anywhere in the house where there’s a power outlet, and there are power outlets every six or eight feet on every wall in the place. So whereas it’s not quite Internet Anywhere, it’s pretty damned close.

I remember thinking with a smirk back when I first got the units that it wouldn’t be too long before somebody made Linux run on it. And suppose somebody did? What would be the use of that?

Well, a use occurred to me a few months later, though it wasn’t anything I felt like discussing at the time. But this morning I saw something on Slashdot that made me change my mind. It’s the Marvell SheevaPlug. It’s an 1.2 GHz ARM-based Linux box in a wall wart, and bears a striking resemblance to the various PowerLine brick bridges that I’ve seen in the last few years. It’s got a gigabit Ethernet port and a USB 2.0 connector, but no other interfaces. You talk to it through the Ethernet port, and can use the USB port for external mass storage or whatever. It takes its power from the wall outlet it’s plugged into. It’s only missing one (obvious) thing: PowerLine connectivity.

One of these plugged into a wall is cute, but not a major win. Equipping them with jelly-bean PowerLine logic changes everything: One plugged into a wall downstairs with a terabyte hard drive on the USB port, and three or four plugged into the wall upstairs acting as USB peripherals to computers, and you’ve got a media distribution system for cheap, with no dependence on CAT5 or even Wi-Fi. You can do that now via Wi-Fi, piecing together a system from components. Products based on the SheevaPlug (which is actually an OEM-able hardware platform) already allow this, with more or less kafeuthering, usually more. (See HipServ and PogoPlug.) My take is that if the idea is in fact to make a cheap and simple media distribution component for home use, PowerLine is a no-brainer.

The SheevaPlug does not have PowerLine connectivity, but someday it or something like it will. And a cheap (in my view, ~$80) implementation could turn an entire hotel into a LAN party–a LAN party where nobody knows precisely who or where anybody else is.

I’m not sure if that’s important to gamers or not. I’m not a gamer and have never been to a LAN party. I have read online, however, that there are LAN parties at which the games are almost a secondary attraction, behind the unusual ability to share files at high speeds with few (if some) concerns about Big Media’s enforcers. At public LAN parties, it’s always possible that the MPAA could plant a mole at the party. But if everybody’s sitting quietly in their hotel rooms either gaming or sharing files (or both) any moles tuning in with their own Sheevas would have a hard time knowing whom to call the cops on. Unlike Wi-Fi, it’s hard to get a directional fix on a PowerLine node, and without routable IP addresses, there’s no way to connect a node to a particular person.

This may or may not be technically feasible; it’s an SF concept for me, and I have a couple of story ideas that follow from it or at least make use of it. Much depends on how hotels are actually wired–and if something like this catches on, I’m guessing that they’ll begin soldering a low-pass filter on the 110v feed to every room.

But in the meantime, it’s cool to see my long-time prediction that computers will eventually become bulges between peripherals moving toward actualization. (I did not guess that computers would become their own wall-warts.) And there’s much more to say about what I call “backnets,” which are networks that happen in unexpected ways, often parasitically on other connections. Backnets may be the third coming of pirate radio, in which tweaking the Man is often more important than accomplishing anything useful. (Is there any fiction about pirate radio out there that you know of? Drop titles in the comments if you’ve got any. Thanks!)


  1. Jeff:

    How bad is the radiated noise on the ham bands?

    I can hear my CAT-5 wired 100 MB/s Ethernet crud out to well over 100 feet from my house. Fortunately my antennas are more than 100 feet from the house. Inside antennas, however, are a sea of interference from computers, switching power supplies and the Ethernet.

    Jack K8ZOA

    1. Interestingly, I haven’t noticed anything new in terms of noise when the PowerLine bricks are plugged in and working. My environment is noisy, most of it coming from computers and (probably) my security system. It was noisier in Arizona, even though my antenna was way off from the house, as best I can tell due to electric fences along two borders of my property there.

  2. vince says:

    I have a SheevaPlug (it was back-ordered for over a month, I’m glad I got one before it got slashdotted).

    It has integer performance roughly equivalent to a 500MHz PIII… but only taking about 10W of power _total_ when running off of a 4GB memory key.

    So this is an interesting turn on the price/performance/power equation. If only there was a floating point unit and a slightly faster processor, it would make sense to have power strips of these things replacing traditional server racks.

    I like the ARM architecture a lot, so it is a shame the Atom performs so well, as it will definitely keep people from migrating.

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