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Skype 5-way Calling Limit Cracked 427

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."
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Skype 5-way Calling Limit Cracked

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  • Lawsuit (Score:4, Insightful)

    by mtenhagen ( 450608 ) on Saturday March 04, 2006 @12:15PM (#14850043) Homepage
    I think this shows this was done on purpose to lock out amd users. A lawsuit by amd should be succesfull.
  • by Anonymous Coward on Saturday March 04, 2006 @12:21PM (#14850067) someone demonstrating that the X2 can in fact handle 9+1 persons at once, which I have no doubt it can. Then it's time for Intel to open up the wallet and give AMD some nice $$$ and some even nicer PR. Stand by to bend over!

  • by tlk nnr ( 449342 ) on Saturday March 04, 2006 @12:29PM (#14850098) Homepage
    Will we see transcripts from depositions done by AMD?
    I'd bet that they will be as funny as some of the SCO transcripts.

    I'd bet that they will depose the programmer who wrote the code encryption and the GenuineIntel check, and then continue with his supervisors.

    Who authorized to add code encryption?
    Who approved it?
    How were the limits to 5 or 10 concurrent connections determined?
  • by dubl-u ( 51156 ) * <> on Saturday March 04, 2006 @12:32PM (#14850116)
    Anybody know anything about their encrypted binary? I can't figure out what they were trying to achieve with that. Some sort of misguided anti-hax0r protection? Or perhaps they're trying to conceal something...
  • Re:Watch out! (Score:2, Insightful)

    by amliebsch ( 724858 ) on Saturday March 04, 2006 @12:35PM (#14850125) Journal
    This has nothing to do with the DMCA or Patriot Act.
  • by Anonymous Coward on Saturday March 04, 2006 @12:43PM (#14850156)

    To anyone doing such testing, make sure the code running is the same that would run on a dual-core Pentium. I didn't follow the patch in detail, but you'd have to make sure that any flags changed after CPU detection (like for instance the one at 0xB8E6DC) is the same for both cases. Else you might find yourself in the situation that, yes, the limit is removed, but you're still running a different ("unoptimized") path. In the (very interesting case) that the code crashes on AMD (due to use of Intel-only prefetch instructions or whatever, I don't even know if such still exists?), such crash can be used to land smack boom right in the relevant code to analyze.

    A good reverse-engineer could then fix the code if needed (substituting or even noping the faulting ops) -- the theory being that the major optimizations are in fact portable.

    In fact, demonstrating that there truly really is only one code-path would be pretty damning too; that's evidence this is just pure PR with no grounding in tech at all. So either case makes for an interesting evening in front of IDA.

  • by thebes ( 663586 ) on Saturday March 04, 2006 @12:53PM (#14850187)
    The software doesn't make a call to the registry or other software settings. The software makes a call to the hard coded cpuid. To get around that, need to a) hack the processor; or b) hack the software making the call.
  • Re:Yay!??? (Score:5, Insightful)

    by bitt3n ( 941736 ) on Saturday March 04, 2006 @01:05PM (#14850237)
    utility is not the point. the point is to stick it to the unctuous twits who crippled their product and lied about the reason.
  • by Svartalf ( 2997 ) on Saturday March 04, 2006 @01:05PM (#14850239) Homepage
    Unless Skype's playing reflector for the whole conference, each peer's connectivity limits what you can/can't do.

    At 128kbps (the average upstream speed on broadband these days in the US...), you can typically host a four to six way voice conference or a 2-3 way video conference. This is because you have to provide the outbound traffic for each of the peers and control traffic. With a reflector system, you can host larger conferences, limited only by the inbound bandwidth because the reflector is flipping the traffic from your mic (and possibly camera...) to all the participants. However, that's REALLY bandwidth intensive, so to keep it economical, you'd probably limit it to 10 participants or so to limit hogging of that limited resource.

    Now, this is all due to everything being unicast UDP. If we had IPv6 and Multicast support for the same available, one could handle at least up to the 10 without needing a reflector as the router infrastructure would handle it right along with the video on demand, etc. streams. However, since this is not likely to happen in our or several generations' lifetimes at the rates things are going, waiting or wishing for that is a waste of time. :-)
  • Indeed... (Score:5, Insightful)

    by Svartalf ( 2997 ) on Saturday March 04, 2006 @01:21PM (#14850297) Homepage
    Considering that SIPPhone already HAS voice conference calls of at least 10 or more, works with ANY SIP enabled device that's not crippled to a single provider (Vonage devices come immediately to mind...), and costs nothing for VoIP calls- I'd say, skip Skype all together, especially after this little stunt.
  • No shit (Score:5, Insightful)

    by grasshoppa ( 657393 ) <skennedy@AAAtpno ... inus threevowels> on Saturday March 04, 2006 @01:24PM (#14850316) Homepage
    It was a made-up limit? No kidding.

    Remember folks; Asterisk. Skype isn't open source, and the company behind it has it's own motives. Asterisk is open source, has a good community behind it, and can do *anything* you want it to. Regardless of the hardware behind it.
  • by aisnota ( 98420 ) on Saturday March 04, 2006 @01:43PM (#14850395) Homepage
    This is a case of DMCA IP Protection being abused for trade protection rights Intel bought and paid for and AMD did not.

    Sherman Anti-trust aside (which this may be a real material breach) it looks like DMCA could either get abridged or affirmed for trade control purposes. For instance, does this mean someone with an Oracle license has the right to use some delta patches to open it wider open on their AMD Opteron for better threading than Intel?

    Hmmm... you see how the lines get to be less than black and white.
  • Two phases, huh? (Score:3, Insightful)

    by Just Some Guy ( 3352 ) <> on Saturday March 04, 2006 @01:47PM (#14850414) Homepage Journal
    The patch is the result of two phases: code analysis and design of the patch.

    In other words, he found the problem then fixed it. Forgive my ignorance, but how else would you possibly go about it? Apply random patches until one kind of works?

  • The Skype software has been preset to only accept Intel's chips as having the performance necessary to host conference calls of more than five people, the representative said.

    If that was said by a representative from Intel then that statement quite qualifies as misrepresenting a competing product. Comparison is perfectly fine, misrepresentation is definitely not and Intel should be forced to compensate for it.
  • Re:10, or more? (Score:2, Insightful)

    by kryptx ( 894550 ) on Saturday March 04, 2006 @01:55PM (#14850449)
    More precisely, I think it means that by modifying the source code, your limits can be imposed by your hardware instead of your software.
  • Re:Aaaah Maxxuss (Score:4, Insightful)

    by Dachannien ( 617929 ) on Saturday March 04, 2006 @02:05PM (#14850482)
    Next stop: HDCP!

    (I hope.)

  • by Saeed al-Sahaf ( 665390 ) on Saturday March 04, 2006 @02:19PM (#14850524) Homepage
    Of course, I'm ignorant. But how come a law suit? Companies make marketing arrangements all the time. What law says Skype has to work with AMD at all? Why should Skype have to write software to work on AMD? No reason at all other than the desire not to alienate a set of users. Skype doesn't have a monopoly on VoIP, if they want to limit their software to Z80s or PowerPC chips, why shouldn't they be allowed to? Market pressures will determine if self-imposed limitations prove workable for Skype, not the politics of Intel hate, and geeks frothing at the mouth...
  • Not "optimized"... (Score:4, Insightful)

    by Svartalf ( 2997 ) on Saturday March 04, 2006 @02:51PM (#14850593) Homepage
    Sound software typically is optimized quite well for both company's offerings, esp. if you don't use special features of the other brand. To be sure, there's edge cases where you need that- but Skype's NOT one of them nor is there evidence that there's the degredation you claim happened with your app experience. (Not to mention that there's tons of other P2P VoIP applications that use SIP and Jabber technology that work as good or better than Skype, and there's other commercial proprietary systems (such as Eyeball Networks' stuff...) that DOES handle up to 10 people (or more as bandwidth will allow...) without needing a dual core anything, let alone an Intel one.)

    This is plain and simple being bought to support one over the other. Please don't try to defend this- it's not something that has much of any good explanation for this, especially considering that they actually DO appear to be just CPUIDing and crippling the app if it's not a dual core Intel CPU...
  • by utlemming ( 654269 ) on Saturday March 04, 2006 @02:55PM (#14850607) Homepage
    Come on. The idea behind declaring a company a monopoly is that consumer choice is limited because of collusion and anti-competitve behavior. In this case, there is some potential to support the idea that Intel and Sykpe may have colluded to create an artificial barrier that is anti-competitive. As a result, it limits consumer choice. When that barrier is arbitrary and is not based on the merrits of the product, for example that AMD chips really don't have some sort of defect that limit the number of telephone calls down to five while an Intel dual core allows up to ten phone calls at the same time, that is anti-competitive. Worse, is when it limits consumer choice and in a business sense, forces a business to adopt a chip that they might not otherwise buy, that is where the issues start to come into play. Merely stating that you don't buy the chip is a straw man arguement. The protections against monopolies where put in to protect the consumer. When companies and monopolies collude, the consumer looses. AMD is outselling their chips -- they can't make them fast enough. Intel might feel threatened, but that is by no means a reason for them to engage in anti-competetive behavior. Also, it is interesting to note that Intel and AMD have agreements for them to coperate together in the development of the x86 instruction set. But Intel doesn't play nice. Intel stopped cooperating with AMD when AMD started to outshine them. It took a judge to order Intel to play nice. Now that AMD is winning the x86-64 game, and has a better server chip, has integrated memory controllers (although Intel does have DDR2 memory, and their mobile chips are about par) people are paying attention to AMD. And an AMD chip is cheaper than an Intel chip. So forcing a company that wants to use the features of Syke or any software to use a particular chip for an arbitarary reason (and Intel verse AMD is arbitarary for the most part) is anti-competitive IF there was any undue influence on the part of the chip maker. If Intel paid any amount of money or applied any pressure that makes the whole arbitarary restriction very illegal and would probably result in an FTC investigation.
  • by Saeed al-Sahaf ( 665390 ) on Saturday March 04, 2006 @03:13PM (#14850687) Homepage
    Personally, I think it shows how incredibly stupid this move was on Intel's part. They're in the middle of an ongoing antitrust suit with AMD and this just gives AMD more ammo to use against them without giving any kind of real gain.

    Ammo against them for what? That they made a business agreement with Skype? Not every distasteful business agreement is illegal.

  • by Stephen Samuel ( 106962 ) <samuel@bc g r e> on Saturday March 04, 2006 @03:42PM (#14850705) Homepage Journal
    Of course, I'm ignorant. But how come a law suit? Companies make marketing arrangements all the time.

    The rules change slightly when you've got a near-monopoly. This is part of what tripped up Microsoft in their anti-trust trials.

    The problem is that it's far easier to convince someone to exclude "the competition" from the market when the competition has a disproportionately small portion of the market.

    For the ease of math, let's say that the Skype market is 90% Intel, 10%AMD. If Intel had to pay Skype 10million to compensate Skype for the lost market in excluding AMD then AMD would have to pay 90million to get Skype to do the same thing. Add to that the fact that Intel has 10x as much income from their larger market share (presuming the same gross profit margin -- which is rarely accurate in a near-monopoly situation) and you have a 90-1 difference in impact on their profit margins.

    Or - - to put it another way, between gross profits and market share, Intel could afford to buy off 100 market slots for every one that AMD could afford to.
    If it came to open warfare like this, AMD would be reduced to a tiny portion of the market and customers would be effectively unable to even find business that deal with AMD. (Dell anyone?). Once you further reduced AMD's market share like this, Intel's ability to further marginalize them would increase until AMD was reduced to an insignificant market access independent of the relative quality of their products.

    It's basically a market-ratio squared relationship which can easily spiral into a near-absolute market ownership, denying customers any real choice in the market no matter how good the competition is. (MS/Linux, anybody?)

    It's actually a worse than ratio squared relationship because we haven't taken into account the probability that, if Intel has a 100-1 ratio of market-exclusionary agreements, they can now charge a higher profit margin without significantly affecting customers' willingness to buy AMD. That, however is harder to quantitize, so I'll only mention it, rather than including it in my math.

    About the only real way to avoid this problem is to create artificial rules designed to stop such market-killing agreements when the market gets too lopsided, to prevent market choice from getting totally destroyed.

  • Re:Lawsuit (Score:3, Insightful)

    by Apathist ( 741707 ) on Saturday March 04, 2006 @03:52PM (#14850734)
    I just don't think they want to support multiple processor instruction sets.
    Unfortunately, that argument just doesn't hold up to scrutiny. The simple fact that a patch exists that allows it to work on AMD chips means that the software does not need to have processor-specific instructions to support the full 10-way calling.

    More to the point, there is so little difference in the instruction sets between the two architectures that it is exceptionally unlikely that any difference is beneficial, let alone necessary.
  • by Saeed al-Sahaf ( 665390 ) on Saturday March 04, 2006 @04:00PM (#14850764) Homepage
    The problem is that Skype tried to blow smoke up our arses, and obviously we don't like that, and get suspicious, and think that something illegal is going on.

    In this case, I would say "get a life." Honestly, getting hot and bothered because "Skype tried to blow smoke up our arses" sounds like childish foot stamping. Show your displeasure with Skype by not using their product, spend your valuble time (it is, right?) doing something productive rather than reactive. By the way, all this frothing and arm waiving will accomplish nothing at all, it's wasted energy. Move on to some other VoIP app in the secure knowledge that due to their greed, Skype will soon be dead. Or part of some spyware package...

  • by Eckzow ( 754643 ) on Saturday March 04, 2006 @04:14PM (#14850816)
    Then you might as well just go write your own patcher. Hell, he told you *exactly* what to do in the article.

    More likely its in a server exterior to the US so some judge-with-a-god-complex can't just rip the server down at a request from the people who run Skype. Injunctions are like candy these days.
  • by Fanboy Troy ( 957025 ) on Saturday March 04, 2006 @04:31PM (#14850867)
    I wonder what your reaction would be if microsoft announced they believe Intel's CPUs aren't powerfull enough to run Vista in all its glory. So if it detects an Intel CPU, you can only open 2 windows at a time. It's microsoft's product, so their free to market it as they like. So either you don't buy Vista which has previously informed you about this limitation (there are plenty of alternatives), or you throw away your Dell... How about if Oracle started thinking the same way and limited the conections to their DB buy CPUID (just so people don't exclude MS for their monopoly)? With all do respect, it isn't so funny now, General 8883 sir, is it? :)

    One thing I also haven't seen pointed out yet is this: Let's say that AMD's CPUs really can't handle 10 conferences at the same time. How can skype guarantee that this will be the case six months down the road. Determining the CPU's capabilities by its manufacturer is lame...
  • by imsabbel ( 611519 ) on Saturday March 04, 2006 @05:48PM (#14851119)
    I think an xp2000 should be enable to push 10 streams via vnware.

    I mean, wtf is supposed to take the cpu power?
    An xp 2000 can compress mp3 in 10 times realtime, for example. Plus in a conference call, you actually send THE SAME to everybody...
    Mixing audio is quasi cpu free (with less than 50 channels or so)
    Sending data over the net is nearly cpu-free.

    So what needs a dual core cpu for 10 connections?
    I would understand that for VIDEO streaming, but its simply inconcievable for audio...
  • by rpdillon ( 715137 ) * on Saturday March 04, 2006 @06:05PM (#14851149) Homepage
    A marketing arrangement, as you call it, is one thing. But in this case, it goes beyond a mere marketing is a very specific type of marketing arrangement in which one company (Skype), in exchange for cash, artificially cripples their product to only work with a certain other (unrelated) product (in this case, dual-core Intel CPUs). The key element here is that the product (Skype) would, if left to it's own devices, work with either Intel or AMD CPUs, but has been crippled in it's use with a certain subset of those artificially.

    This is really a form of product tying [], which was made illegal by the Sherman Antitrust Act (1890), but only if a non-trivial amount of business is affected by the tying. This last requirement will likely be the reason the suit isn't successful, but that certainly dosn't mean that the behavior isn't borderline, at best.

    Again, this isn't a compatibility issue, as you said, "Why should Skype have to write software to work on AMD?" The real question is "Why should Skype be allowed to artificially exclude AMD users in exchange for money from AMD's competitor?"

  • by Saeed al-Sahaf ( 665390 ) on Saturday March 04, 2006 @07:16PM (#14851424) Homepage
    Yes, complaining about fraud is childish foot stamping.

    It's not fraud. Get your facts and definitions correct. Talking like a lawyer does not make you a lawyer.

  • Re:Lawsuit (Score:3, Insightful)

    by ( 653730 ) on Sunday March 05, 2006 @10:47AM (#14853516)
    I really don't understand how they're going to get users to upgrade. If anything, this harms Skype. If I can't ru skype on a amd....i'll use...another VOIP program.

"I shall expect a chemical cure for psychopathic behavior by 10 A.M. tomorrow, or I'll have your guts for spaghetti." -- a comic panel by Cotham