How do mobile cards package idle traffic and send short messages?

"Play at will" 10 yuan leisure time package: 10 yuan/month, including 1.5GB of leisure time traffic in the province, used from 23: 00 to 7: 00 the next day (non-leisure time internet traffic, excess leisure time traffic and internet traffic outside the province are charged according to your original package traffic tariff standard). The monthly capping fee is 500 yuan, and the capping flow is 15GB. If it exceeds 15GB, you need to turn this function on again. You can directly reply to the message "66", which will be opened in the same month and take effect immediately. "Play at will" 5 yuan leisure time package: 5 yuan/month, including 500MB of leisure time traffic in the province, which can be used from 23: 00 to 7: 00 the next day (non-leisure time internet traffic, excess leisure time traffic and internet traffic outside the province are charged according to your original package traffic tariff standard). The monthly capping fee is 500 yuan, and the capping flow is 15GB. If it exceeds 15GB, you need to turn this function back on. You can directly reply to the message "66", which will be opened in the same month and take effect immediately.