A data transmission method, comprising: receiving (101, 301) a create or update message of a PDP context or a bearer sent by a sending end, wherein the create or update message carries a quality of service parameter; and characterized by: determining (102, 302), according to the quality of service parameter, whether a user plane tunnel of a bearer corresponding to the PDP context or a user plane tunnel of the bearer can be encapsulated through a UDP-Lite protocol, and returning, to the sending end, a response message carrying determination result information, so that when the determination result information indicates that encapsulation can be performed through the UPD-Lite protocol, the sending end encapsulates the user plane tunnel of the bearer corresponding to the PDP context or the user plane tunnel of the bearer will be encapsulated through the UDP-Lite protocol by the sending end; wherein the determining, according to the quality of service parameter, whether the user plane tunnel of the bearer corresponding to the PDP context or the user plane tunnel of the bearer can be encapsulated through the UDP-Lite protocol, comprises: acquiring a first threshold and a second threshold; and determining, whether a code error resilience in the quality of service parameter is greater than the first threshold and whether a packet loss tolerance in the quality of service parameter is greater than the second threshold, and if both yes, determining that the user plane tunnel of the bearer corresponding to the PDP context or the user plane tunnel of the bearer can be encapsulated through the UDP-Lite protocol. receiving (101, 301) a create or update message of a PDP context or a bearer sent by a sending end, wherein the create or update message carries a quality of service parameter; and characterized by: determining (102, 302), according to the quality of service parameter, whether a user plane tunnel of a bearer corresponding to the PDP context or a user plane tunnel of the bearer can be encapsulated through a UDP-Lite protocol, and returning, to the sending end, a response message carrying determination result information, so that when the determination result information indicates that encapsulation can be performed through the UPD-Lite protocol, the sending end encapsulates the user plane tunnel of the bearer corresponding to the PDP context or the user plane tunnel of the bearer will be encapsulated through the UDP-Lite protocol by the sending end; wherein the determining, according to the quality of service parameter, whether the user plane tunnel of the bearer corresponding to the PDP context or the user plane tunnel of the bearer can be encapsulated through the UDP-Lite protocol, comprises: acquiring a first threshold and a second threshold; and determining, whether a code error resilience in the quality of service parameter is greater than the first threshold and whether a packet loss tolerance in the quality of service parameter is greater than the second threshold, and if both yes, determining that the user plane tunnel of the bearer corresponding to the PDP context or the user plane tunnel of the bearer can be encapsulated through the UDP-Lite protocol. acquiring a first threshold and a second threshold; and determining, whether a code error resilience in the quality of service parameter is greater than the first threshold and whether a packet loss tolerance in the quality of service parameter is greater than the second threshold, and if both yes, determining that the user plane tunnel of the bearer corresponding to the PDP context or the user plane tunnel of the bearer can be encapsulated through the UDP-Lite protocol.