  In this work we give an example of exponential separation between quantum and
classical resources in the setting of XOR games assisted with communication.
  Specifically, we show an example of a XOR game for which $O(n)$ bits of two
way classical communication are needed in order to achieve the same value as
can be attained with $\log n$ qubits of one way communication.
  We also find a characterization for the value of a XOR game assisted with a
limited amount of two way communication in terms of tensor norms of normed
spaces.
