A method for operating an Internet of Things device after completion of a binding process with a user equipment, the method comprising: receiving, by user equipment, an operation instruction for an Internet of Things device initiated by a user to operate the Internet of Things device; receiving, by the user equipment, a random number from the Internet of Things device, wherein the random number is generated by and stored in the Internet of Things device; identifying, by the user equipment, a biometric feature of the user; verifying, by the user equipment, an identity of the user based on the biometric feature; signing, by the user equipment if the identity of the user is verified successfully, the operation instruction by using a first user key of the user; transmitting, by the user equipment, both the random number and the signed operation instruction to the Internet of Things device; verifying, by the Internet of Things device, a signature for the signed operation instruction by using a second user key of the user, wherein the second user key and the first user key constitute a key pair; comparing, by the Internet of Things device after the signature is verified successfully, a random number received from the user equipment with the random number generated by the Internet of Things device; executing, by the Internet of Things device, the operation instruction only when the random number received by the Internet of Things device from the user equipment and the random number generated by the Internet of Things device are consistent and if the signature is verified successfully; and invalidating, by the Internet of Things device, the random number after the operation instruction is executed, thereby ensuring that the operation instruction is executed only once. receiving, by user equipment, an operation instruction for an Internet of Things device initiated by a user to operate the Internet of Things device; receiving, by the user equipment, a random number from the Internet of Things device, wherein the random number is generated by and stored in the Internet of Things device; identifying, by the user equipment, a biometric feature of the user; verifying, by the user equipment, an identity of the user based on the biometric feature; signing, by the user equipment if the identity of the user is verified successfully, the operation instruction by using a first user key of the user; transmitting, by the user equipment, both the random number and the signed operation instruction to the Internet of Things device; verifying, by the Internet of Things device, a signature for the signed operation instruction by using a second user key of the user, wherein the second user key and the first user key constitute a key pair; comparing, by the Internet of Things device after the signature is verified successfully, a random number received from the user equipment with the random number generated by the Internet of Things device; executing, by the Internet of Things device, the operation instruction only when the random number received by the Internet of Things device from the user equipment and the random number generated by the Internet of Things device are consistent and if the signature is verified successfully; and invalidating, by the Internet of Things device, the random number after the operation instruction is executed, thereby ensuring that the operation instruction is executed only once.