  The conjugacy search problem in a group G is the problem of recovering an x
in G from given g in G and h=x^{-1}gx. This problem is in the core of several
recently suggested public key exchange protocols, most notably the one due to
Anshel, Anshel, and Goldfeld, and the one due to Ko, Lee at al.
  In this note, we make two observations that seem to have eluded most people's
attention. The first observation is that solving the conjugacy search problem
is not necessary for an adversary to get the common secret key in the Ko-Lee
protocol. It is sufficient to solve an apparently easier problem of finding x,
y in G such that h=ygx for given g, h in G.
  Another observation is that solving the conjugacy search problem is not
sufficient for an adversary to get the common secret key in the
Anshel-Anshel-Goldfeld protocol.
