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Wireless PCIe To Enable Remote Graphics Cards
J. Dzhugashvili writes "If you read Slashdot, odds are you already know about WiGig and the 7Gbps wireless networking it promises. The people at Atheros and Wilocity are now working on an interesting application for the spec: wireless PCI Express. In a nutshell, wPCIe enables a PCI Express switch with local and remote components linked by a 60GHz connection. The first applications, which will start sampling next year, will let you connect your laptop to a base station with all kinds of storage controllers, networking controllers, and yes, an external graphics processor. wPCIe works transparently to the operating system, which only sees additional devices connected over PCI Express. And as icing on the cake, wPCie controllers will let you connect to standard Wi-Fi networks, too."
We'll soon have ONE MORE wireless signal to keep track of, when all those we already have work so well together!
You'd better get used to your computer experience looking like thaaaaaaaaat if your display has to be sennnnnnnnt over a wireless linnnnnk.
The best feature of this proposed standard is that if you place a ceramic mug directly between your CPU and the external graphic processor, it will keep your (coffee, soup or whatever) steaming hot, all day long! Those days of long WoW raids with only cold beverages and snacks are over!
You catch enchiladas by picking them up behind the head and holding them underwater until they don't kick anymore -VeGas
Very short. It has a hard time going through air; walls - forget it.
Not to mention security. I mean, you thought Tempest was bad before, now I can wirelessly sniff and alter PCI traffic, which is a direct conduit into the RAM.
Cool! Amazing Toys.
Some recent systems have IOMMUs which provide privilege separate between hardware devices much like normal MMUs govern software. However, unless this sort of IOMMU device is active, PCI and PCIe hardware is generally capable of transferring data to or from any other connected device, including any area of system RAM. Sometime this can even extend to external interfaces; for example, people have been known to take advantage of the DMA capabilities of the Firewire protocol to read the contents of RAM on an active system.
In general, non-hotpluggable hardware has been granted the same level of trust as the OS kernel, so no one worried very much about it. IOMMUs were more about protecting against faulty or corrupted software (device drivers) than malicious hardware. However, more and more hardware is hotpluggable these days. Also, some software interfaces are becoming too complex to really trust—consider, for example, the interface to a modern GPU, which must transfer data to and from RAM, and perhaps other GPUs, under the control of code provided by user-level application software (shaders, GPGPU). Without an IOMMU it is up to the driver software to prove that such code is perfectly safe, which is an inherently hard problem.
"The state is that great fiction by which everyone tries to live at the expense of everyone else." - Bastiat
It's not that bad -- I've done it before.
X Windows over plain old wifi.
You're unlikely to be able to *alter* PCI traffic, though you could perhaps *insert* PCI traffic.
Still, people figured out properly encrypting wireless links some time ago. Tempest is primarily interesting because the signals you're looking at are unintentional (and often unknown) side effects and they often deal with links that are impossible or unreasonable to encrypt.
"I imagine it will be impractical for many devices"
You're right, and the summary is wrong and the article's a bit misleading.
"... will let you connect your laptop to a base station with all kinds of storage controllers, networking controllers, and yes, an external graphics processor."
Sorta... PCIe 16x is 16 GB/s, that's with a big B for bytes. They're hoping for 7Gbps, or 875 MB/s. "the spec should move "quickly" to 7Gbps (875MB/s)." That's 1/20th the speed of 16x PCIe. They might be able to do PCIe x1 but that's it.
If they would have read the whitepaper that is all explained:
"A reliable wPCIe connection can be maintained with a relatively low data rate channel. However, to achieve meaningful performance between local and remote devices, the data rate needs to be on the order of 2 Gbps, or that of a single lane of PCIe. The only practical wireless channel that can support this capacity is 60 GHz."
So basically this can transfer wirelessly at ~500+ MB/s, so you can have wireless BD-ROM, wireless hard drives, and yes even wireless displays, since it's fast enough to transfer 1080i without any compression, but I'm sorry to dash the hopes of anyone that thought they could someday upgrade their laptop's video card by simply buying a wireless external Radeon HD 5970 or Geforce GTX 480, you will still need a GPU connected by 16x PCIe to process the video and then stream it similar to what OnLive Remote Gaming Service offers now.
my karma will be here long after I'm gone
What are the possibilities of channel bonding, though? WiFi has 11 channels, is it possible to build a sender/receiver pair that can move data over multiple channels at once? Perhaps soon there will be 7Gbit, then 14Gbit, then 21Gbit, etc implementations. Need more bandwidth? Add more radios.
True, but consider this possibility:
Right now everyone's looking at the traditional model. That is, a portable CPU connected to a GPU connected to a display, and adding in a wireless form factor to it.
What if, instead, the base station contained the CPU AND the GPU connected directly together - much like a desktop system now - to do all the hard math and 3D rendering? - which then outputs a wireless PCIe signal, which is then picked up by the portable device, like a netbook, with a basic GPU, a small processor, and little to no HD space? It's only job would be, much like a thin client - would be to provide you access to the computing power in the "main" section of the house.
It would be like having a docking station for your netbook that turns it into a desktop powerhouse - only you could walk around the house with it. And, when the time comes that you want to take it outside, you still have the basic capabilities of a netbook.
That might be a product worth selling to, say, a family of four. "You can pay for four notebooks, or four netbooks and this powerful base station".
I used to work for NetQoS. I no longer do, but want to keep the excellent karma attached to this account.