Of course, this information could be sent over a standard telephone line as well, but giving every vending machine a fixed telephone connection for one call a day is expensive on account of the fixed monthly charge.

• 当然，这些信息也可以通过电话来发送，但是，给每台贩卖机安装固定电话，并且每天只打一次电话，这样带来的费用是非常高的，因为每个月都有固定的月租费。