Mitchell Institute for Fundamental Physics & Astronomy
College Station, Texas 77843
We construct families of conformal boundary states for the bosonic model with target space T^2/(Z_2)^2. We use such D-branes to obtain conformal defects which glue together c=1 CFTs with the target space S^1/Z_2. We identify what it means for a conformal defect to be topological when twisted degrees of freedom appear in the theory.