Data Transmission Method, System and Related Network Device Based on Proxy Mobile (pm) Ipv6

1. A data transmission method based upon a Proxy Mobile Internet Protocol version 6, PMIPv6, comprising: establishing, by a Mobile Access Gateway, MAG, and a Local Mobility Anchor, LMA, a bidirectional tunnel based upon binding of a service flow through interaction of messages after a Mobile Node, MN, initiates the service flow, wherein a downlink Generic Routing Encapsulation, GRE, key and an uplink GRE key are allocated to the service flow and the LMA adds a binding relationship between a service flow identifier of the service flow and address information of the MN during establishment of the bidirectional tunnel; and transmitting, by the MAG and the LMA, a data packet of the service flow initiated by the MN over the bidirectional tunnel according to the service flow identifier, the binding relationship, and the uplink and downlink GRE keys, wherein establishing by the MAG and the LMA the bidirectional tunnel through interaction of messages after the MN initiates the service flow comprises: transmitting, by the MAG, to the LMA a first proxy binding update message instructing to add binding of the service flow upon reception of a first data packet of the service flow initiated by the MN, wherein the first proxy binding update message comprises the service flow identifier generated for the service flow and the downlink GRE key allocated to the service flow; and adding, by the LMA, the binding relationship between the service flow identifier and the address information of the MN according to the received first proxy binding update message and returning to the MAG a first proxy binding acknowledge, ack, message comprising the service flow identifier and the uplink GRE key allocated to the service flow.

2. The method of claim 1 , wherein transmitting by the MAG and the LMA a data packet of the service flow initiated by the MN over the bidirectional tunnel according to the service flow identifier, the binding relationship, and the uplink and downlink GRE keys comprises: encapsulating, by the MAG, an uplink data packet of the service flow from the MN according to the service flow identifier and the uplink GRE key and forwarding the encapsulated uplink data packet to the LMA over the bidirectional tunnel, and de-encapsulating, by the LMN, the encapsulated uplink data packet according to the service flow identifier and the uplink GRE key and forwarding the de-encapsulated uplink data packet to a Correspondent Node, CN; and encapsulating, by the LMA, a downlink data packet of the service flow from the CN according to the service flow identifier and the downlink GRE key and forwarding the encapsulated downlink data packet to the MAG over the bidirectional tunnel, and de-encapsulating, by the MAG, the encapsulated downlink data packet according to the service flow identifier and the downlink GRE key and forwarding the de-encapsulated downlink data packet to the MN.

3. The method of claim 1 , wherein transmitting, by the MAG, to the LMA a second proxy binding update message instructing to delete binding of the service flow upon determining that the MN terminates the service flow, wherein the second proxy binding update message comprises the service flow identifier; and deleting, by the LMA, the locally buffered binding relationship between the service flow identifier and the address information of the MN according to the received second proxy binding update message and returning to the MAG a second proxy binding ack message comprising the service flow identifier.

4. The method of claim 1 , wherein the proxy binding update message further comprises an application level description and/or a transport level description of the service flow.

5. The method of claim 1 , wherein the proxy binding ack message further comprises an application level description and/or a transport level description of the service flow.

6. The method of claim 4 , wherein the application level description comprises a service identifier and/or an application level protocol in use.

7. The method of claim 4 , wherein the transport level description comprises one or any combination of Destination, Internet Protocol, IP Address, Port Range, Flow Label, Security Parameter Index, Protocol Identifier of the protocol above IP, and Type of Service/Traffic class and Mask.

8. The method of claim 5 , wherein the application level description comprises a service identifier and/or an application level protocol in use.

9. The method of claim 5 , wherein the transport level description comprises one or any combination of Destination, Internet Protocol, IP Address, Port Range, Flow Label, Security Parameter Index, Protocol Identifier of the protocol above IP, and Type of Service/Traffic class and Mask.

10. A data transmission system based upon a Proxy Mobile Internet Protocol version 6, PMIPv6, comprising a Mobile Access Gateway, MAG, and a Local Mobility Anchor, LMA, the MAG comprising a first memory storing a first set of instructions instructing a first processor to perform first operations, the LMA comprising a second memory storing a second set of instructions instructing a second processor to perform second operations, wherein: the first and second operations comprise: establishing a bidirectional tunnel based upon binding of a service flow through interaction of messages after a Mobile Node, MN, initiates the service flow, wherein a downlink Generic Routing Encapsulation, GRE, key and an uplink GRE key are allocated to the service flow and the LMA is further configured to add a binding relationship between a service flow identifier of the service flow and address information of the MN during establishment of the bidirectional tunnel; and transmit a data packet of the service flow initiated by the MN over the bidirectional tunnel according to the service flow identifier, the binding relationship and the uplink and downlink GRE keys, wherein: the first operations further comprises transmitting to the LMA a first proxy binding update message instructing to add binding of the service flow upon reception of a first data packet of the service flow initiated by the MN, wherein the first proxy binding update message comprises the service flow identifier generated for the service flow and the downlink GRE key allocated to the service flow; and to receive a first proxy binding acknowledge, ack, message returned from the LMA in response to the first proxy binding update message, wherein the first proxy binding ack message comprises the service flow identifier and the allocated uplink GRE key; and the second operations further comprise adding the binding relationship between the service flow identifier and the address information of the MN according to the received first proxy binding update message and return the first proxy binding ack message to the MAG.

11. The system of claim 10 , wherein: the MAG is first operations further comprise encapsulating an uplink data packet of the service flow from the MN according to the service flow identifier and the uplink GRE key and forward the encapsulated uplink data packet to the LMA over the bidirectional tunnel, and de-capsulating an encapsulated downlink data packet data packet according to the service flow identifier and the downlink GRE key and forward the de-encapsulated downlink data packet to the MN; and the second operations further comprise encapsulating a downlink data packet of the service flow from a Correspondent Node, CN, according to the service flow identifier and the downlink GRE key and forward the encapsulated downlink data packet to the MAG over the bidirectional tunnel, and de-capsulating an encapsulated uplink data packet according to the service flow identifier and the uplink GRE key and forward de-encapsulated uplink data packet to the CN.

12. The system of claim 10 , wherein: the first operations further comprise transmitting to the LMA a second proxy binding update message instructing to delete binding of the service flow upon determining that the MN terminates the service flow, wherein the second proxy binding update message comprises the service flow identifier; and the second operations further comprise deleting the locally buffered binding relationship between the service flow identifier and the address information of the MN according to the received second proxy binding update message and return to the MAG a second proxy binding ack message comprising the service flow identifier.

13. A Mobile Access Gateway, MAG, comprising: a microprocessor; a non-transitory computer readable storage medium with an executable program stored thereon, wherein the program instructs the microprocessor to perform operations comprising: transmitting to a Local Mobility Anchor, LMA, a first proxy binding update message instructing to add binding of a service flow upon reception of a first data packet of the service flow initiated by a Mobile Node, MN, wherein the first proxy binding update message comprises a service flow identifier generated for the service flow and a downlink Generic Routing Encapsulation, GRE, key allocated to the service flow; receiving a first proxy binding acknowledge, ack, message returned from the LMA in response to the first proxy binding update message, wherein the first proxy binding ack message comprises the service flow identifier and an uplink GRE key allocated to the service flow; and transmitting a data packet of the service flow over a bidirectional tunnel established, based upon binding of the service flow, with the LMA, according to the service flow identifier and the uplink and downlink GRE keys.

14. The MAG of claim 13 , wherein the operations further comprise transmitting to the LMA a second proxy binding update message instructing to delete binding of the service flow upon determining that the MN terminates the service flow, wherein the second proxy binding update message comprises the service flow identifier.