What is the origin or history of the concept of 'Buddha Sasana"?

There is some information here at wikipedia I am curious to know if that came from Buddha himself or mentioned in any suttas. The 'sasana' concepts restricts appearence of solitary buddhas or Prateyakabuddhas or paccekabuddhas (as described in Isigili Sutta and Rhinocerous Sutta) without a Sangha. Any thoughts...