  The paper proposes an alternative proof that Omega, an oracle that outputs a
process identifier and guarantees that eventually the same correct process
identifier is output at all correct processes, provides minimal information
about failures for solving consensus in read-write shared-memory systems: every
oracle that gives enough failure information to solve consensus can be used to
implement Omega.
  Unlike the original proof by Chandra, Hadzilacos and Toueg (CHT), the proof
presented in this paper builds upon the very fact that 2-process wait-free
consensus is impossible. Also, since the oracle that is used to implement can
solve consensus, the implementation is allowed to directly access consensus
objects. As a result, the proposed proof is shorter and conceptually simpler
than the original one.
