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Skype Protocol Has Been Reverse Engineered
An anonymous reader writes "One researcher has decided he wants to make Skype open source by reverse engineering the protocol the service uses. In fact, he claims to have already achieved that feat on a new skype-open-source blog. The source code has been posted for versions 1.x/3.x/4.x of Skype as well as details of the rc4 layer arithmetic encoding the service uses. While his intention may be to recreate Skype as an open source platform, it is doubtful he will get very far without facing an army of Microsoft lawyers. Skype is not an open platform, and Microsoft will want to keep it that way."
And yet we have several programs that can read/write to Office files. It seems the same could be done with MS Skype - call it OpenSkype or LibreSkype.
The only problem is the potential to be sued for theft-of-service (making calls w/o paying).
Information wants to be expensive AND wants to be free. So you have Value vs. Cheap distribution fighting each other.
Just because the protocol is reverse engineered doesn't make it open. I would rather see an open standard become supported or used by Skype/Microsoft.
Let's play video games with mailmanZERO
Facetime has much better video quality for low-bandwidth connections, and there is no Window's application for it. That would be a better target.
This could be the Skype killer we have been wishing for. It doesn't have to work with Skype, it just has to be as good as Skype and to be open. Imagine people being able to set up their own private Skype-like servers for personal and business use... even for home-monitoring uses and more. Skype will undoubtedly kill support for Linux and probably restrict access in a variety of ways. While being able to access Skype servers and services would be desirable, I wouldn't expect that to be allowed to work and would end up as the arms race we saw previously in instant messaging. (One that I think was ultimately lost or abandoned by those trying to fight 3rd party clients.) But if a truly free and open Skype-like set of clients and servers were made available, a lot of useful things can occur.
It's protected. Lawyers may bark, and pound a table or two, but ultimately, they'll fail.
Sec. 103(f) of the DMCA (17 U.S.C. 1201 (f)) says that if you legally obtain a program that is protected, you are allowed to reverse-engineer and circumvent the protection to achieve the ability the interoperability of computer programs
The remaining question to ask is what’s the point of doing this reverse engineering? Skype is a free-to-use service for the most part. You do pay for non Skype-to-Skype calls, and have to use the official software, but is that really enough to make users desire an alternative?
Yes.
sysadmins and parents of newborns get the same amount of sleep.
Here's the torrent if it gets taken down. http://thepiratebay.org/torrent/6442887
No. You do realize most encryption algorithms are published for all to see, right? Unless Skype is doing something very stupid in the key exchange, it's just as secure as before.
Live today, because you never know what tomorrow brings
What? Whatever you're smoking, please share.
The ease of developing a tool has nothing to do with whether or not it is popular. They're completely unconnected. Ease of use might have something to do with it, but ease of development is entirely unrelated. VOIP apps ARE easy to develop. Encrypted voice apps ARE easy to develop (once you've converted the analog audio to digital audio you can apply any encryption algorithm you like with whatever key-exchange protocol you like). Getting a large userbase on a given standard is one part luck, two parts MBA-bullshit--as I said, entirely unrelated.
Reverse engineering is an absolute necessity for compatibility, and compatibility is often an absolute necessity for success. Being the best product often isn't enough.
This is my signature. There are many like it, but this one is mine.
Emerson was the first one to popularize the myth that if one were to "Build a better mousetrap, and the world will beat a path to your door", and yes for the pedants out there I realize this is a misquotation of what Emerson really said, but the juice of it is a maxim that many individuals use to understand the process of innovation. Unfortunately, when observed through the lens of history, the maxim does not hold water.
The truth about innovation is that it occurs when the right mix of entities are brought together in a way that has never been done before to create a distinct advantage in the market. To illustrate this point, look at what Henry Ford did with the Model-T and how he altered the landscape of factories throughout the world. He didn't invent new technologies, he took technologies being utilized in other industries and adapted them for his needs. Thereby allowing for a streamlined factory where metal came in one end, and completed cars came out the other end. There are many entities involved in innovation and I've merely down a fly-over of what Henry Ford did, but I think it helps to illustrate the point that I was making at the beginning ... Being the best product is never enough.
Ease of use might have something to do with it, but ease of development is entirely unrelated.
Thank you for so succinctly summing up the single greatest problem with Linux and most other open source software.
Ease of use *IS* part of development. It's just as much a requirement as any other technical aspect.
Also, like most nerds, you have vastly underestimated the difficulty in developing an application. It's easy to whiteboard a simple voice chat app, and *fairly* simple to create some sort of intercom-type chat program. But once you start adding things like central directories, low-latency variable bandwidth calling over the internet, and the like, you end up with difficulty even coming up with a reasonable whiteboard outline, and the actual implementation becomes quite difficult. By no means impossible, but it's not something you'll bang out over a weekend and be on par with something like Skype.
As awful as Skype may be, just because you understand the idea behind how it works doesn't mean it's easy to duplicate. This is a classic nerd mistake.
The third zipfile contains no less than 443,000 lines of code (not counting a number of duplicates under _old), including ports to Virtual C++, Borland C and Gcc under Unix, different versions of the protocol parser, and so on. The few bits I've looked at are written competently and with confidence, there's none of the "this byte is 42 in all messages, I don't know why" that you'd expect in reverse-engineered code.
It's either a leak of Skype's code, or a decompilation; it's certainly not a reimplementation. --jch
Reverse engineering in itself is no easy task, and once you have the protocol reverse engineered you still need to build a program to use it. 1 guy did this where it takes a multibillion dollar company to screw up the technology (skype has been steadily getting worse in terms of quality, reliability, and usability).
An example of how it works well is mIRC - one guy built it, others expanded on it, there's various flavours from stand alone programs to browser plugins, to website integration and it's been free and is to this day one of the best chat room programs available.
None of that would have been possible had he patented/enforced copyright on it.
I just needed to get this out of my system.