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Skype 5-way Calling Limit Cracked
BobPaul writes "It turns out when Skype limited 10 way calling to Intel Processors only it really was arbitrary! Maxxus has a patched version of Skype that allows 10-way calling regardless of the processor installed. There's also info about the patch: "The patch is the result of two phases: code analysis and design of the patch. The code analysis, or reverse engineering, reveals the relevant code block, which overrides Skype's limitation for Intel's dual-core CPUs. The patch design isolates the minimal set of instructions that need to be modified to cancel this limitation." Windows only so far."
Since this limit was "arbitrary", that means the only deciding factor was not technology, but money. I wonder how much the block cost Intel?
And now that it's in the open, (like that was going to take very long?) I wonder if they'll remove the block?
I work for the Department of Redundancy Department.
Skype made a lot of noise in their press release saying that the 10-way feature was "optimized" for Intel chips. This was picked up by the media of course as well as evidence of AMD's poor performance.
I'm having trouble understanding what this optimization that used the special features of Intel chips (presumably their high power) was. It looks from the patch that they just check who the manufacturer is, and if it is not AMD, they pretend your computer doesn't have the power to host 10 participants.
What's also interesting is that folks likely signed up for SkypeOut and other paid products not realizing that they would be treated differently depending on what chipsets they happen to use, especially as that choice matters almost no where else. They should give more warning about this to paid users.
This focus on locking software into specific vendor chips seems a dangerous one. No longer will it be the best chip that will win, but the focus goes to competing on locking up software applications. The proprietary unix'es went down that path, and it would be sad if Intel managed to get that to happen here.
So what is now limiting the conference calls to 10 people now? Is that a phone company limit, or another arbitrary limit?
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Or, so as not to break other programs that use cpuid (to determine which instructions they can run, for example) perhaps this could be done in a user-space way.
I'm thinking of artsdp as a model, so you would just launch your Skype client with something like "cpufake --cpuid='Genuine Intel Dual Core We Like Skype' skype.bin" (or whatever it's called.)
I've got no idea how such a program would work, but the article did say the code was encrypted so I wonder if that would be an issue.
Being in a company who worked exclusively on Intel and nVidia chips until recently, it is possible to have horrible performance when switching to AMD and ATI. In our case, we didn't use any nVidia specific GL calls. As for SS2, it is supported on both platform so in theory it shouldn't be an issue. The reality is, unless you are making a game and using what I'd call "game-oriented opengl calls", the performance is going to vary a LOT between ATI and nVidia. Don't believe the hype of these companies when they say that they support full OpenGL. Some either have very bad hardware for 2d ops with OpenGL or literally do software "decelleration". Benchmarks have shown speed dropping as much as 200% in some areas. As for AMD and Intel, after patching the executable, the performance was different, sometimes in favor of Intel, sometimes on AMD.
With that being said, no platform specific instructions or features were used. I suspect the Skype guys may have simply used Intel machines for so long and never bothered using AMD machines for development and then were too lazy to simply rewrite some of the code so that it runs normally on AMD. This happens especially when you write tight assembly loops by taking into account instruction latencies for one processor and then realize the performance sucks on another platform. You then have the choice, rewrite it so that the performance is similar, or slap a OPTIMIZED FOR INTEL on the box.
Thankfully we rewrote.
Of interest here is also the code marked with (*). It reveals that the string is somehow used if a certain memory location has the value 4. Theory is, this 4 means "4 additional conference members";
Is that possible that by modifying some variables...we can have unlimited number of user in the conference?
This sounds an awful lot like the type of code built by Intel's compilers, for which they're being sued by AMD. Is it possible Skype is using that very compiler, and just couldn't figure out how to make it work on AMD machines (presumably pre-lawsuit)?
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Svartalf, you are indeed insightful today. Personally I use Asterisk meetme conferences for all my conferencing needs. Only limited to my server horsepower and available bandwidth. Can have almost an unlimited number of people call into it through SIP, IAX2 or an IAX2 trunked PTSN #.
I tried skype a couple times (mostly because some girl talked me into it), but she wasn't worth it. The lack on interoperability totally killed it. The last thing I need is yet another app running on my main console all the time. Asterisk runs happilly on my server in the corner and rings my normal home phones all over the house if someone is trying to reach me. I might even pay for a skype IAX2 or SIP access account. But being a closed system they are too much trouble to deal with.
Yeah, except they're not locking out just AMD users. They're also locking out anybody who has an Intel chip that doesn't meet their arbitrary requirements. So to me it sounds more like a forced obsolescence plan to get people to upgrade to higher end PCs.
Can't you get the OS to look through the code before it's executed and replace the offending instruction with a simulated version, like they do to workaround the pentium f00f bug?
I am trolling
Seems it has allready been done.
Skype didn't break any laws, and no one (except /.ers) said they did. It's their software and if they want to intentionally limit their customer based they are more than welcome to do so.
The reason this issue is important is that it seems likely Intel went to Skype, and in some way coerced/bribed them to do this. This could be extremely strong evidence in helping AMD with their current lawsuit against Intel. Hence AMD issuing a subpoena to Skype, to retrieve information that will show whether or not Intel is to blame for this limitation.
It's silly to hear people saying AMD should sue Skype. AMD doesn't care about skype, nor are they trying to run a huge campaign of lawsuits. They are only interested in forcing Intel to stop their current tactics which have arguably kept AMD from massive success in the OEM market.
Big ones, small ones, some as big as yer 'ead!
Give 'em a twist, a flick o' the wrist...
Maybe you should go and *read* the DMCA. It specifically allows reverse engineering for compatibility reasons.
Oh well, what the hell...
I think I'd have to say no, this is different from that. The "aero" GUI actually requires a better graphic card. That is no different from similar GUIs on Linux--they also require better graphics cards.
One might argue that it does "force obsolescence" because Windows is so ubiquitous--you want to be able to run Vista, you gotta have an nVidia (sp?). But that isn't the case either, as you can turn off "aero" and use the "classic" look, which requires a less sophisticated graphics card.
Nice try giving a shot at Bill though...
The restriction isn't of the form "this software uses instruction X, which your processor doesn't support", it's of the form "we don't run unless your processor id string is X". The case is that the AMD chip does everything the Intel chip does (at least in the realm of instructions that the Skype software requires), except that it says "AMD" rather than "Intel" when you ask it where it's from.
"Because Science" is one step from "Because old book". Try "Because of my experiment testing my falsifiable assertion".
It would lose sales for them, though.
:(
Exactly. So, why would skype want to make such a move if it obviously would lose sales from it also? If Intel has a hand in this, I don't see how it is legal for Intel and skype to make a deal that would make AMD and/or other CPUs look bad when they most likely can handle the conferences. Or if not, they can probably 'catch up' with Intel really quick. I don't know how the law works in the USA exactly and IANAL, but this sort of defamation is illegal in Europe (I don't know how much this is relevant to this situation). It's one thing to add value to skype when you buy Intel (optimize it for intel CPUs) and another thing to remove value when you buy AMD (remove features it probably is capable of handling), ultimately making AMD look bad unfairly.
I could be sort of ok with this if it was a QoS thing, but if it was, it shouldn't have been implemented by checking for the chips manufacturer and th user should be given the opportunity to "use at his own risk". At least skype should have announced the feature Intel's CPUs have AMD lacks. I think this is a dangerous road to go down. Imagine a future where you would choose the programs you run based on the manufacturer of the CPU you use. Even worse, imagine the deadlocks where you need to run 2 programs that favor different manufacturers. The worst part being that the 'obsticales' are completely artificial. And the competition wouldn't be on each cpu's merits, but on the manufacturer's connections.
The requirement is that the Intel chip returns a 'GenuineIntel' signature, which, if the chip IS an Intel chip, any Intel chip (at least since they introduced such ID signatures on chips) should be every single Intel chip. So yes, it pretty much is AMD they're locking out. It should be interesting to see how this revelation pans out in court with AMD already pressing charges to this effect, this article should be all the evidence they really need, although the courts have done weirder things in the past. I hope that such evidence as presented here is allowed into court.
Has anyone tested whether Skype allows 10-way conference calls on any of the Macs powered by the Intel Core Duo?
There is no lawsuit vs Skype. AMD has an ongoing anti-trust lawsuit vs Intel, and they subpoenaed Skype to find evidence that Intel had Skype put in the pointless restriction. Many other companies have already been similarly subpoenaed including most major PC manufacturers.
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