Hi,

in order to build composite field of GF((2^2)^2)^2 i need 3 irreducible polynomial as the following

r(z) = z^2 + \lambda z + 1 for GF(2^8)/GF(2^4)
s(y) = y^2 + \{\delta+1\}y + 1 for GF(2^4)/GF(2^2)
t(x) = x^2 + x + 1 for GF(2^2)/GF(2)

how do i determine all the 8 possible value for \lambda?

thanks in advance