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As the topic says, since when can ECC cryptography be freely used?

Isn't it widely used because of patents? There is no alternative to it on embedded devices and smart cards.

Just to mention: I am not from the USA. I'm a simple user who wants ECC to be wide supported.

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A lot depends on how ECC is used. Most patents cover specific aspects which many implementations don't use at all. – CodesInChaos Feb 27 '13 at 14:35
My impression is that as long as you use a software implementation of a prime curve without point compression, you're probably not violating any patents. (As usual IANAL applies) – CodesInChaos Feb 27 '13 at 15:14

Let me preface this by saying that I am not a lawyer and if you are planning on using ECC in a system you sell, you should hire a lawyer.

There are a number of ECC related patents. However "in all of these cases, it is the implementation technique that is patented, not the prime or representation, and there are alternative, compatible implementation techniques that are not covered by the patents" (src). That said, the patents last 20 years, the implementation techniques that are patented might be freely usable (I say might because I believe there are other legal mechanisms to protect IP) 20 years after the patent was applied for. A very quick survey showed that many of the patents on the Wikipedia page were applied for in the late 80's to late 90's. Thus, by 2020 the currently existing patents should expire.

ECC can presumably be used without infringing on the patents. So, the patents themselves are not necessarily inhibiting widespread use. There are some who would argue that the real reason ECC isn't widely used is due to it's age and the fact that RSA came first. Age lends credibility (the longer it has been around w/o a break the more the community trusts it).

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Removed some comments from a previous version of the answer – mikeazo Feb 27 '13 at 15:04
I'd like to add that it's probable that RSA is also more used due to it's comparative simplicity. You can do an example encryption with small constants on your graphical calculator. Elliptic curve encryption requires some more serious math. – orlp Sep 13 '13 at 17:38

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