Finite 2-arc-transitive abelian Cayley graphs

Let Γ be a finite 2-arc-transitive Cayley graph of an abelian group. It is shown that either Γ is explicitly known, or Γ 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: View the MathML source where n is even but is not a 2-power, Γ has 2-power number of vertices, or Γ is a circulant.