We present a straightforward model of cosmic-ray propagation in the Galaxy that can account for the observed cosmic-ray positrons entirely as secondary products of cosmic-ray nucleons interacting with the interstellar medium .
In addition to accounting for the observed energy dependence of the ratio of positrons to total electrons , this model can accommodate both the observed energy dependence of secondary to primary nuclei , like Boron/Carbon , and the observed bounds on the anisotropy of cosmic rays .
This model also predicts the energy dependence of the positron fraction at energies higher than have been measured to date , with the ratio rising to \sim 0.7 at very high energies .
We briefly point out the differences between this model and the model currently in wide use that does not account for the observed positrons as secondaries and so prompts the interpretation of the observations as evidence for alternate origins of positrons .