Entropy of bosonic open string and boundary conditions

The entropy of the states associated to the solutions of the equations of motion of the bosonic open string with combinations of Neumann and Dirichlet boundary conditions is given. Also, the entropy of the string in the states |Ai〉=αi−1|0〉 and |φa〉=αa−1|0〉 that describe the massless fields on the world-volume of the Dp-brane is computed.