A method includes determining, by an NFCC of a first NFC device, whether the NFCC is responsible for determining a maximum length value of data packets transmitted in subsequent communication. The method further includes sending a first request comprising a first length value to a second NFC device when the NFCC is responsible for determining the maximum length value. The first request further includes a first DID. The method further includes receiving a first response that is returned by the second NFC device for the first request and that comprises a second DID. The method further includes using the first length value as the maximum length value of the data packets transmitted in the subsequent communication when the first DID is the same as the second DID.