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The target users would be portable/embedded devices or resource limited code (i.e. javascript). The idea being that the devices could poll the service for validated primes and use them for encryption functions.

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Wolfram Alpha? – schroeder Dec 14 '11 at 2:10
up vote 3 down vote accepted

Probably not. If I need large prime numbers, I will want to pull them from a trusted source using a secure method. To do that, I'll either need pre-shared keys or I'll have to use something like SSL. If I'm using SSL, I'm probably consuming a fair bit of CPU...

A chicken and egg problem at the very least, and trust issues after that.

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I don't know of anyone who pulls the prime from a trusted online source via SSL or some other secured remote connection. That's unnecessary complexity. All the implementations I've seen either hardcode the prime, or generate a random prime themselves as part of the key generation process. – D.W. Dec 14 '11 at 3:26
@D.W.... which is exactly why I'm saying that this service likely isn't useful. – Jeff Ferland Dec 14 '11 at 4:20

No. Not useful at all. The systems that need large primes usually have the prime hardcoded into the program. This is because we need to know that the prime was generated by a trustworthy source.

Polling an online service would open up an undesirable and unnecessary security dependency: if the online service feeds you a bad prime, then the security of your system would get broken. And it's unnecessary; in almost every case, a better solution is to hardcode the prime in your program (or, in the rare case where that is not sufficient, generate your own prime; that's not something you need to do frequently).

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