We have explored the magnetosphere described by a numerical solution for an axisymmetric rotating field satisfying the force-free and ideal MHD conditions everywhere. The electric current distribution is determined by the requirement of continuity and smoothness of the flux function across the light cylinder. The overall magnetic field structure is obtained using the numerical result. We also checked the drift velocity of a charged particle, which is caused by the resultant electric and magnetic fields. It is found that the velocity exceeds the light speed beyond a few times the size of the light cylinder. This fact suggests the breakdown of some underlying assumptions.