The trip code is the communication big data trip card a code is also equivalent to the health code, is by the China Academy of Information and Communication Technology in conjunction with China Telecom, China Mobile, China Unicom three basic telecommunications enterprises to use the data received by the cell phone, through the user's cell phone is located in the location of the base station to obtain, for the country's 1.6 billion cell phone users free of charge to provide query services, cell phone users can be used through the service, to query the I have been to all the previous 14 days of the city information.

One of the basic priorities of epidemic prevention and control is traceability, tracking, that is, traceability, and does not care about the quality of the user or the individual, because one of the premise is that what can come out and circulate must be good, otherwise the relevant organizations or individuals, need to be responsible for this.