# Elliptic Curve Over Extension Field
## Metadata
**Status**:: #x
**Zettel**:: #zettel/literature
**Created**:: [[2024-03-25]]
**Topic**:: [[♯ Cryptography]]
## Synopsis
Elliptic Curve over extension field $F_{p^k}$ uses the non-prime field $\mathrm {GF} (p^k)$ (**see**:: [[Finite Field]]) to define the curve polynomial.
Taking the [[Elliptic Curve|Weierstrass Curve]] as an example
$
y^2 = ax^3 + bx + c
$
If the curve is defined over $\mathrm{GF}(p^k)$, all the variables $x, y$, and coefficients $a, b, c$ are polynomials in $\mathrm{GF}(p^k)$. Since $\mathrm{GF}(p^k)$ is a field, all the operations defined in [[Elliptic Curve]] and [[Elliptic Curve Over Finite Field]] also works for the extension field.
Elliptic Curve Over Extension Field must use [[Extension Field Arithmetic]] for all computations.