System and method of unacknowledged network layer service access point identifier (NSAPI) recovery in sub-network dependent convergence protocol (SNDCP) communication

1. A method, comprising:

receiving a reset exchange identification (XID) command at a Logical Link Control (LLC) of a mobile station (MS);

resetting all LLC XID parameters to their default values;

discarding all requests that are pending from a layer-3 communication layer to a plurality of logical link entities (LLEs);

receiving a logical link reset indication (LL-RESET-indication) from the LLC at a Sub-Network Dependent Convergence Protocol (SNDCP) layer; and

upon receipt of the LL-RESET-indication, the performing the following acts at the SNDCP:

resetting all SNDCP XID parameters to their default values;

for every network service access point identifier (NSAPI) using unacknowledged peer-to-peer LLC operation, setting a sequence number of the next network packet data unit (N-PDU) to be sent by the SNDCP to zero;

if the NSAPI is using unacknowledged peer-to-peer LLC operation, then:

transmitting outstanding SNDCP-to-LLC requests to the LLC.

2. The method of claim 1 , comprising the further acts of:

before receiving the XID command:

performing a GSM task;

suspending GPRS service; and

buffering the one or more SNDCP-to-LLC requests in the LLC.

3. The method of claim 2 , comprising the further acts of:

performing a routing area network update, thereby resulting in the reset XID command being received by the LLC after the buffering by the LLC of the one or more SNDCP-to-LLC requests.

4. The method of claim 2 , wherein the act of performing a GSM task comprises performing a MS location area update, the method further comprising the act of:

performing a GPRS task by the MS after suspending the GPRS service.

5. The method of claim 2 , wherein the GPRS task comprises sending an electronic mail (e-mail) message.

6. The method of claim 1 , wherein the SNDCP-to-LLC requests include logical link unit data requests.

7. The method of claim 1 , wherein the SNDCP-to-LLC requests comprise logical link XID requests.

8. A method of resetting Sub-Network Dependent Convergence Protocol (SNDCP) reset exchange identification (XID) parameters, initializing SNDCP unacknowledged Network Service Access Point Identifier (NSAPI) network packet data unit (N-PDU) numbers, and recovering outstanding unacknowledged NSAPI requests, comprising the acts of:

receiving, from a Logical Link Control (LLC) layer, a logical link reset indication (LL-RESET-indication) at the SNDCP;

upon receipt of the LL-RESET-indication, the performing the following acts at the SNDCP:

resetting all SNDCP XID parameters to their default values;

for every network service access point identifier (NSAPI) using unacknowledged peer-to-peer LLC operation, setting a sequence number of the next N-PDU to be sent by the SNOOP to zero; and

if the NSAPI is using unacknowledged peer-to-peer LLC operation: transmitting outstanding SNDCP-to-LLC requests to the LLC.

9. A method of layer-2 recovery comprising the acts of:

identifying a layer-2 reset condition in layer-3;

after identifying the layer-2 reset condition, identifying outstanding layer-3 to layer-2 requests for unacknowledged layer-2 communication; and

resending outstanding layer-3 to layer-2 requests from layer-3 to layer-2;

upon identifying the reset condition in layer-3;

setting unacknowledged layer-2 communication sequence numbers to zero in layer-3; and

entering a recovery state in layer-3 for acknowledged layer-2 communications.

10. A mobile station, comprising:

a receiver;

a transmitter;

an antenna coupled to the receiver and the transmitter;

one or more processors including:

a layer-2 module which interfaces with the receiver and the transmitter;

a layer-3 module which interfaces with the layer-2 module;

the layer-3 module being operative to facilitate data communication for the mobile station by sending a plurality of requests to a queue of the layer-2 module, each request being a type that is acknowledged by the layer-2 module but unacknowledged by a destination node; and

the layer-3 module being further operative to resend one or more requests that are unacknowledged by the layer-2 module in response to a reset indication;

the layer-3 module being further operative to set, in response to the reset indication at the layer-3 module, a packet data unit (PDU number to zero for use in resending the one or more requests.

11. The mobile station of claim 10 , wherein the requests comprise unacknowledged Network Layer Service Access Point Identifier (NSAPI) requests.

12. The mobile station of claim 10 , further comprising:

the layer-2 module comprising a Logical Link Control (LLC) layer; and the layer-3 module comprising a recovering Sub-Network Dependent Convergence Protocol (SNDCP) layer.

13. A method of communicating data comprising:

facilitating data communication by sending a plurality of requests from a layer-3 module to a queue of a layer-2 module, each request being a type that is acknowledged by the layer-2 module but unacknowledged by a destination node; and

in response to a reset indication, resending one or more requests that are unacknowledged by the layer-2 module;

in response to the reset indication at the layer-3 module, setting a packet data unit (PDU number to zero for use in resending the one or more requests.

14. The method of claim 13 , wherein the requests comprise unacknowledged Network Layer Service Access Point Identifier (NSAPI) requests.

15. The method of claim 13 , wherein the layer-2 module comprises a Logical Link Control (LLC) layer and the layer-3 module comprises a recovering Sub-Network Dependent Convergence Protocol (SNDCP) layer.