  We study the transition between parallel and intersecting branes on a torus.
Spontaneous symmetry breaking of nonabelian gauge symmetry is understood as
brane separation, and a more general intermediate deformation is discussed. We
argue that there exists supersymmetry preserving transition and we can always
have parallel branes as a final state. The transition is interpreted due to
dynamics of the F- and D-string junctions and their generalization to (F, D$p$)
bound states. The gauge group and coupling unification is achieved, also as a
result of supersymmetry. From the tadpole cancelation condition, we naturally
have some class of intersecting brane models as broken phases of Type I theory
with SO(32) gauge group.
