To obtain a mechanism which give advantages to both a seller who desires prepayment and a purchaser who desires postpayment after article reception confirmation, when an article is sold and purchased through a network.

This is a network deposit, and a purchaser makes a deposit of money for purchasing an article temporarily at a specific institution and pays the money from the specific institution after receiving and confirming the article. Consequently, a risk that the purchaser has upon purchase of the article is reduced, and the risk in settlement by sending the article that the seller has is reduced, since the purchaser makes the deposits of the money at the specific institution.