MAC Address changeability/reliability

[rolfk]

I'm telling you to go ask where people are likely to know. If they will answer is of course another question.

Rolf Kalbermatter

[battler.]

If you do not know that is ok.  I'm sure someone else may.

The idea of this tread was to start a discussion about peoples experience.  Please don't speak for everybody else if you have NO experience.

I will leave it to NI to tell me where to go, thank you.

[rolfk]

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battler. wrote:

If you do not know that is ok.  I'm sure someone else may.

The idea of this tread was to start a discussion about peoples experience.  Please don't speak for everybody else if you have NO experience.

I will leave it to NI to tell me where to go, thank you.

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Have your way! It seems you are quickly annoying most people here.

Rolf Kalbermatter

[Coq_Rouge]

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battler. wrote:

If you do not know that is ok.  I'm sure someone else may.

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"A fool may ask more questions in an hour than a wise man can answer in seven years" proverb from Swift 1738

[Neil.Pate]

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battler. wrote:

If you do not know that is ok.  I'm sure someone else may.

The idea of this tread was to start a discussion about peoples experience.  Please don't speak for everybody else if you have NO experience.

I will leave it to NI to tell me where to go, thank you.

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That last comment leaves yourself quite open to sarcastic replies 😉

[battler.]

Way too busy to care.

[GerdW]

Hi battler,

also too busy to care for netiquette?

Or to care for good answers to your question? (you asked for specific information and got an answer who might know what you're after...)

Well, it seems like every new thread of yours should get a linked "double post" answer to message#16 of this thread...

[smercurio_fc]

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battler. wrote:
Way too busy to care.

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Ditto.

[memoryleak]

MAC addresses are relatively painless to edit (http://www.irongeek.com/i.php?page=security/changemac).  Most routers even have it built into the first page or so (!very! useful when a CounterStrike server bans your IP because if you change your MAC address and restart your cable modem you often get assigned a new IP from your ISP!  Headshot!).  

So to answer your question, the MAC Addresses are changable by any 11 year old.  (Read: not very reliable)

You might try assigning your client a key (RSA is fairly straightforward http://en.wikipedia.org/wiki/RSA) and having them sending you a message encryped with it.  Barring feats of factorization, you can be pretty certain that you are indeed talking with who you think you are.  (For bonus points and much love, post your RSA VIs here for others to use!)

Hugs,

memoryleak 

[memoryleak]

I made the assumption in my previous post that you wanted to secure an application against being used by anyone other than your customer (by creating a password based on some number unique to their computer).  

If you instead wanted to secure an application against the same customer using it on multiple computers the problem is quite different 🙂  I don't have an answer in this case, but I do have some example solutions that I interact with every day!

1) License checkout.  Every time I want to use xyzSoftware, my computer contacts a local server and requests a license for that software.  I hold that license until I close the program, and there is a limit to the number of licenses that can be checked out at any given time.  For an even more commonplace example, most multiplayer games could be thought of as using a similar mechanism where you are checking out the sole "license" that is associated with your activation code whenever you log in.

2) Physical keys.  See #1 but replace "license server" with "usb stick that allows me to use the program"

If you want to go yet further and only allow a single person to run your software on a specific single computer, the problem gets even MORE difficult.  For instance, I have a 16GB virtual machine that lives on my home network.  I use it for things when I'm at home, and whenever I hit the road I just zap it over to my laptop and can continue right where I left off.  The virtual machine thinks it's still on the same computer.

If you come up with a clever solution to this, I'd be interested in hearing about it 🙂

Hugs,

memoryleak