Complex sentence: Brastel Telecom ブラステル株式会社 or more commonly known as Brastel, is a Japanese telecommunications company based in Tokyo; they distribute international prepaid calling cards within Japan and Asia via convenience stores.
Split into simpler sentences: Brastel Telecom ブラステル株式会社 most commonly known as Brastel, is a Japanese telecommunications company based in Tokyo. They distribute international prepaid calling cards within Japan and Asia via convenience stores.