ภูมิภาค Then we find the distance of all ONUs with the users. According to minimum distance from the user, we identify the primary ONU of all the users. After identifying the primary ONUs, we try to minimize the average distance between the ONU and the user. The Greedy Algorithm is a heuristic, which performs local optimization of an individual ONU after the identification of premium users for that ONU, but this solution is not globally optimal.