Correspondence stations are all certified by the state and cannot be faked. You can know whether they are correspondence stations or not.

Correspondence station refers to the teaching point set up by colleges and universities that have the right to carry out adult education. Most of the areas where schools are not resident are prefecture-level cities. As long as the school you apply for has a correspondence station in your local area, you don't have to go to school. Take classes at the correspondence station. The effect is the same, nothing more than providing convenience to many students!