EC ElGamal
point=f(x, y)
G - point (public)
d - integer (private)
Q=dG - point (public)
x - integer [secret integer] (public)
M=f(x, y) - point [coordinate calculation] (public)
C=xG - point [secret point] (public)
E=xQ+M - point [point addition] (public)
(C, E) - message [(xG, xdG+M)] (public)
D=d*C - point [point multiplication] (private)
M=E−D - point [((xdG+M)-dxG)] (private)
only works from public key to private key

EC DH
- each side generates a secret integer k and multiplies with point G
- each side sends their point multiplication result to the other
- each side multiplies their secret integer with the exchanged point