Method and Apparatus for Establishing a Virtual Link, Wireless Lan, and Method for Transmitting Data

Abstract

The embodiments of the present invention provide a method and an apparatus for establishing a virtual link. The method includes the following steps: a virtual link establishment requesting end initiates a virtual link establishment request which contains virtual link negotiation parameters of the requesting end to a requested end through a base link; the requested end receives the virtual link establishment request, parses the request and obtains the virtual link negotiation parameters of the requesting end, and negotiates between the obtained parameters with the virtual link parameters of local end to obtain negotiated virtual link parameters; the requested end determines the virtual link end-point address identifications; the requested end sends a virtual link establishment response which contains the negotiated virtual link parameters and the virtual link end-point address identifications to the requesting end through the base link; the requesting end receives the response, parses the response and obtains the negotiated virtual link parameters and the virtual link end-point address identifications; the identification of the virtual link is accomplished for the requesting end and the requested end.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the 802.11 network architecture in the prior art;

FIG. 2 shows a schematic diagram of STA states;

FIG. 3 shows a schematic diagram of the correspondence between one base link and multiple virtual links according to an embodiment of the present invention;

FIG. 4 shows a schematic diagram of establishing virtual links between an STA and an AP according to an embodiment of the present invention;

FIG. 5 shows a flow chart of virtual link establishment initiated by an STA according to an embodiment of the present invention;

FIG. 6 shows a flow chart of virtual link establishment initiated by AP according to an embodiment of the present invention;

FIG. 7 shows a flow chart of virtual link establishment according to an embodiment of the present invention;

FIG. 8 shows a flow chart of data transmission by using a virtual link apparatus according to an embodiment of the present invention;

FIG. 9 shows a flow chart of virtual link deletion according to an embodiment of the present invention;

FIG. 10 shows a flow chart of virtual link establishment by means of an association request according to an embodiment of the present invention.

Claims

1. A method for establishing a virtual link, comprising: initiating a virtual link establishment request to a requested end by a virtual link establishment requesting end through a base link; the request containing virtual link negotiation parameters of the requesting end;upon receiving the virtual link establishment request, negotiating by the requested end between the parsed out virtual link negotiation parameters of the requesting end and local virtual link parameters of its own to obtain negotiated virtual link parameters;determining the virtual link end-point address identifications by the requested end;sending a virtual link establishment response to the requesting end by the requested end through the base link; the response containing the negotiated virtual link parameters obtained and the virtual link end-point address identifications;upon receiving the response, parsing the response and obtaining the negotiated virtual link parameters and the virtual link end-point address identifications by the requesting end; and accomplishing the identification of the virtual link for the requesting end and the requested end.

2. The method according to claim 1, wherein the virtual link establishment requesting end is a Station (STA), and the requested end is an Access Point (AP).

3. The method according to claim 1, wherein the requested end determines the virtual link end-point address identifications through the following steps: when the virtual link establishment request initiated by the virtual link establishment requesting end to the requested end through the base link carries the virtual link end-point address identification of the requesting end, the requested end assigns the local virtual link end-point address identification of its own after parsing the request and obtaining the virtual link end-point address identification of the requesting end, and thereby obtains the virtual link end-point address identifications; or when the virtual link establishment request initiated by the virtual link establishment requesting end to the requested end through the base link carries the virtual link end-point address identifications of the requesting end and the requested end, the requested end takes the parsed out virtual link end-point address identifications of the requesting end and the requested end as the end-point address identifications of the virtual link; orwhen the virtual link end-point address identification information carried in the virtual link establishment request message initiated by the virtual link establishment requesting end to the requested end through the base link is empty, the requested end assigns the virtual link end-point address identifications for the requesting end and the requested end, and takes the assigned identifications as the end-point address identifications of the virtual link.

4. The method according to claim 1, wherein the virtual link end-point address identifications comprise the end-point addresses of the requesting end and requested end, or, the virtual link end-point address identifications comprise end-point addresses of the base link and port numbers of the requesting end and requested end.

5. The method according to claim 1, wherein the method further comprises: after the requested end sends the virtual link establishment response, assigning a local virtual link number by the requested end for itself; or, when the requesting end receives the virtual link establishment response sent from the requested end, assigning a local virtual link number by the requesting end for itself.

6. The method according to claim 1, wherein the parameters comprise at least virtual link binding information, security parameters, and Quality of Service (QoS) parameters.

7. The method according to claim 1, wherein there is disposed a counter at each end of the virtual link; when the virtual link is established, the counters are increased by 1, and when the virtual link is deleted, the counters are decreased by 1.

8. The method according to claim 1, wherein the method further comprises: sending virtual link establishment capability information by the two ends waiting for virtual link establishment and determining by the two ends whether a virtual link may be established between them.

9. The method according to claim 8, wherein the AP waiting for virtual link establishment sends the virtual link capability information in a Beacon Frame or a Probe Response Frame; the STA receives the virtual link capability information when it scans the channels and thereby determines whether a virtual link may be established between the AP and itself.

10. The method according to claim 8, wherein the method further comprises: sending the virtual link capability information in an association request or the virtual link establishment request by the STA waiting for virtual link establishment; after the AP receives the virtual link capability information, judging by the AP whether a virtual link may be established between the STA and itself.

11. The method according to claim 8, wherein the virtual link establishment capability information comprises whether the two ends waiting for virtual link establishment support multiple Media Access Control (MAC) addresses; or, the virtual link capability information comprises: whether the two ends support virtual link and virtual link end-point address assignation policy.

12. The method according to claim 1, wherein when either end of the virtual link receives a virtual link deletion request, it sends a virtual link deletion message through the virtual link, and releases relevant local resources; when the other end of the virtual link receives the virtual link deletion message, it releases relevant resources.

13. An apparatus for establishing a virtual link which is adapted to establish the virtual link based on a base link and comprises a negotiation module and an end-point address identification setting module; wherein the negotiation module is adapted to create and initiate to the requested end a virtual link establishment request containing virtual link negotiation parameters; to receive and parse a request message from a requesting end, and negotiate between the obtained virtual link negotiation parameters and the local virtual link parameters to obtain negotiated virtual link parameters; and to determine a local virtual link end-point address identification and send a virtual link establishment response message which contains the negotiated virtual link parameters and the virtual link end-point address identifications to the requesting end;the end-point address identification setting module is adapted to parse the received response message to obtain the negotiated virtual link parameters and the virtual link end-point address identifications.

14. A station (STA), comprising an apparatus for establishing a virtual link which is adapted to establish the virtual link based on a base link and comprises a negotiation module and an end-point address identification setting module; wherein the negotiation module is adapted to create and initiate to the requested end a virtual link establishment request containing virtual link negotiation parameters; to receive and parse a request message from a requesting end, and negotiate between the obtained virtual link negotiation parameters and the local virtual link parameters to obtain negotiated virtual link parameters; and to determine a local virtual link end-point address identification and send a virtual link establishment response which contains the negotiated virtual link parameters and the virtual link end-point address identifications to the requesting end;the end-point address identification setting module is adapted to parse the received response to obtain the negotiated virtual link parameters and the virtual link end-point address identifications.

15. An Access Point (AP), comprising an apparatus for establishing a virtual link which is adapted to establish the virtual link based on a base link and comprises a negotiation module and an end-point address identification setting module; wherein the negotiation module is adapted to create and initiate to the requested end a virtual link establishment request containing virtual link negotiation parameters; to receive and parse a request message from a requesting end, and negotiate between the obtained virtual link negotiation parameters and the local virtual link parameters to obtain negotiated virtual link parameters; and to determine a local virtual link end-point address identification and send a virtual link establishment response which contains the negotiated virtual link parameters and the virtual link end-point address identifications to the requesting end;the end-point address identification setting module is adapted to parse the received response to obtain the negotiated virtual link parameters and the virtual link end-point address identifications.

16. A Wireless LAN (WLAN), comprising at least one Basis Service Set (BSS), wherein when the WLAN includes multiple BSSs, the BSSs are connected to each other via a Distribution System (DS); each of the at least one BSS comprises at least one Station (STA) associated with an Access Point (AP); the STA comprises an apparatus for establishing a virtual link, and the AP comprises an apparatus for establishing a virtual link; the apparatus for establishing a virtual link is adapted to establish the virtual link based on a base link, and comprises a negotiation module and an end-point address identification setting module; the negotiation module is adapted to create and initiate to the requested end a virtual link establishment request containing virtual link negotiation parameters; to receive and parse a request message from a requesting end, and negotiate between the obtained virtual link negotiation parameters and the local virtual link parameters to obtain negotiated virtual link parameters; and to determine a local virtual link end-point address identification and send a virtual link establishment response which contains the negotiated virtual link parameters and the virtual link end-point address identifications to the requesting end;the end-point address identification setting module is adapted to parse the received response to obtain the negotiated virtual link parameters and the virtual link end-point address identifications.

17. A method for transmitting data through a Wireless LAN (WLAN), comprising: sending a data message request by a MAC user at a data transmission requesting end to the local MAC layer; the request containing a Media Access Control (MAC) source address and a MAC destination address, a virtual link number, and the data message to be sent;after the MAC layer at the data transmission requesting end receives the request, determining a Transmitter Address (TA) and a Receiver Address (RA), by the MAC layer, according to the virtual link number, and then constructing an address field in MAC data frame header by the MAC layer according to the TA, the RA, the source address and the destination address, and sending the data message by the MAC layer to the MAC layer at the requested end through the virtual link;sending, by the MAC layer at the data transmission requested end, a data message indication carrying the MAC user source address, the MAC user destination address, the virtual link number, and the received data message to the local MAC user at the requested end.

18. The method according to claim 17, wherein as specified in 802.11 protocol and according to the security mechanism corresponding to the virtual link, the data message is segmented and encrypted to construct one or a series of MAC protocol data messages, and sent to the data transmission requested end; the requested end decrypts the received one or a series of data messages and reconstructs the one or a series of segmented data messages.

19. The method according to claim 18, further comprising: after sending the data message, sending a data message state indication by the MAC layer at the transmission data requesting end to the local MAC user; the indication containing the state, the source address, and the destination address of the data message sent through the virtual link, as well as the virtual link number.