Joke Collection Website - Public benefit messages - What letter should I send a short message to check GPRS traffic?

What letter should I send a short message to check GPRS traffic?

Send the short message "CXLL" to "100 10"

This is Unicom

Sending the short message "CXGPRS" to "10086" is mobile.

Send a text message from "108" to "1000 1". This is for telecommunications.

You can also call the customer service of each communication operator.

hope this helps