Information Query Method, Device, and System

An information query method, comprising:

• acquiring, by a second device, a data-excluded information query request frame sent by a first device and comprising first control information and a first hash value, wherein the first hash value is a hash value generated after first information is computed by using a first hash function, wherein the data-excluded information query request frame does not comprise a target address, and wherein the first control information comprises at least first indication information used for indicating a type of the data-excluded information query request frame;
• sending, by the second device, a data-excluded information query response frame when the second device has second information corresponding to the first hash value, wherein the data-excluded information query response frame comprises second control information, a second hash value, and an address of the second device, so that the first device sends a data-contained information query request frame to the second device when the first device determines that a third hash value is consistent with the second hash value, wherein the third hash value is a hash value generated after the first device computes the first information by using a second hash function, wherein the data-contained information query request frame comprises the address of the second device and an address of the first device, wherein the second hash value is a hash value generated after the second device computes the second information by using the second hash function, wherein the data-excluded information query response frame does not comprise a target address, and wherein the second control information comprises at least second indication information used for indicating the type of the data-excluded information query request frame;
• and
• responding, by the second device, to the data-contained information query request frame when receiving the data-contained information query request frame.

A communications device, comprising:

• a transmitter configured to send a data-excluded information query request frame, wherein the data-excluded information query request frame comprises first control information and a first hash value, wherein the first hash value is a hash value generated after first information is computed by using a first hash function, wherein the data-excluded information query request frame does not comprise a target address, and wherein the first control information comprises at least first indication information used for indicating a type of the data-excluded information query request frame;
• a receiver configured to receive a data-excluded information query response frame sent by a second device, wherein the data-excluded information query response frame comprises second control information, a second hash value, and an address of the second device, wherein the second hash value is a hash value generated after the second device computes second information by using a second hash function, wherein the data-excluded information query response frame does not comprise a target address, and wherein the second control information comprises at least second indication information used for indicating the type of the data-excluded information query request frame;
• and
• a processor separately coupled with the transmitter and the receiver, wherein the processor is configured to:
• parse the data-excluded information query response frame received by the receiver, to obtain the second hash value;
• and
• determine whether a third hash value is consistent with the second hash value, wherein the third hash value is a hash value generated after the first information is computed by using the second hash function,
• wherein the transmitter is further configured to send a data-contained information query request frame to the second device when the processor determines that the third hash value is consistent with the second hash value, and
• wherein the data-contained information query request frame comprises the address of the second device and an address of the communications device, so that the second device responds to the data-contained information query request frame when receiving the data-contained information query request frame.

A communications device, comprising:

• a receiver, configured to acquire a data-excluded information query request frame sent by a first device and comprising first control information and a first hash value, wherein the first hash value is a hash value generated after first information is computed by using a first hash function, wherein the data-excluded information query request frame does not comprise a target address, and wherein the first control information comprises at least first indication information used for indicating a type of the data-excluded information query request frame;
• a processor coupled to the receiver, wherein the processor is configured to:
• parse the data-excluded information query request frame received by the receiver, to obtain the first hash value;
• and
• determine whether the communications device has second information corresponding to the first hash value;
• and
• a transmitter coupled to the processor and configured to send a data-excluded information query response frame when the processor determines that the communications device has the second information corresponding to the first hash value, wherein the data-excluded information query response frame comprises second control information, a second hash value, and an address of the communications device, so that the first device sends a data-contained information query request frame to the communications device when the first device determines that a third hash value is consistent with the second hash value, wherein the third hash value is a hash value generated after the first device computes the first information by using the second hash function, wherein the data-contained information query request frame comprises the address of the communications device and an address of the first device, wherein the second hash value is a hash value generated after the processor computes the second information by using the second hash function, wherein the data-excluded information query response frame does not comprise a target address, and wherein the second control information comprises at least second indication information used for indicating the type of the data-excluded information query request frame, and
• wherein the processor is further configured to respond to the data-contained information query request frame when the data-contained information query request frame is received.