  Multireader shared registers are basic objects used as communication medium
in asynchronous concurrent computation. We propose a surprisingly simple and
natural scheme to obtain several wait-free constructions of bounded 1-writer
multireader registers from atomic 1-writer 1-reader registers, that is easier
to prove correct than any previous construction. Our main construction is the
first symmetric pure timestamp one that is optimal with respect to the
worst-case local use of control bits; the other one is optimal with respect to
global use of control bits; both are optimal in time.
