Finite 2-arc-transitive abelian Cayley graphs

Let ΓΓ be a finite 2-arc-transitive Cayley graph of an abelian group. It is shown that either ΓΓ is explicitly known, or ΓΓ may be represented as a normal or bi-normal Cayley graph of an abelian or a meta-abelian 2-group. In particular, one of three cases occurs: Γ=Kn,n−nK2 where nn is even but is not a 2-power, ΓΓ has 2-power number of vertices, or ΓΓ is a circulant.