There are a lot of websites where it is claimed something akin to this but no explanation on the basis. 

"ECC key size of 256 bits is equivalent to a 3072-bit RSA key and 10,000 times stronger than a 2048-bit RSA key"

**Q:** What is the basis of this claim about the 10K factor? Where does the 10K come in?

I see the comparable key sizes from this [table](https://www.nsa.gov/business/programs/elliptic_curve.shtml) (this is referred everywhere).

Also, a [link](https://casecurity.org/2014/06/10/benefits-of-elliptic-curve-cryptography/) where the claim is made. BTW: This is not the only site that makes this claim.