# US 9,438,384 B2 · Providing multiple retransmission policies for a single data stream by mapping differentiated services code point (DSCP) bit fields to media access control protocol data unit (MPDU) bit fields > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,384 B2 - Document ID: US9438384B2 - Status: Granted - Kind: B2 - Application number: 13/043,202 - Filed: 2011-03-08 - Published: 2012-09-13 - Granted: 2016-09-06 - Earliest claimed: 2011-03-08 - Assignees: QUALCOMM Incorporated - Applicants: Maarten Menzo Wentink - Inventors: Maarten Menzo Wentink - Web page: https://patentgrep.com/patent/US9438384B2 ## CPC - H04L 1/1877: {for semi-reliable protocols, e.g. for less sensitive applications like streaming video (buffer level management for video bitstream control arrangements H04N21/44004)} - H04L 1/1825: Adaptation of specific ARQ protocol parameters according to transmission conditions - H04L 1/1887: {Scheduling and prioritising arrangements} - H04L 1/1896: {ARQ related signaling} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract One feature provides for a method operational at an access point in communication with a destination station where the access point receives a stream of data including at least one media access control protocol data unit (MPDU) having a Differentiated Services Code Point (DSCP) field value, provides a retransmission policy to the MPDU based on the DSCP field value, and transmits the MPDU to the destination station via a wireless local area network. The stream of data may include a stream of video data having a layered modulation scheme, where the DSCP field value identifies at least one layer of the layered modulation scheme. The access point may use deep packet inspection to retrieve the DSCP value from the MPDU. In this fashion, multiple retransmission policies may be provided for a single data stream by mapping DSCP field values to MPDU bit fields, such as the Traffic Identifier field. ## Claims ### Claim 1 A method operational at an access point in communication with a destination station, the method comprising: receiving a stream of data including at least one media access control protocol data unit (MPDU) having a Differentiated Services Code Point (DSCP) field value, wherein the stream of data has a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme; providing a retransmission policy to the MPDU based on the DSCP field value by replacing a first Traffic Identifier (TID) field value with a second TID field value, wherein the retransmission policy identifies a maximum number of retransmissions of the MPDU to the destination station; and transmitting the MPDU to the destination station via a wireless local area network (WLAN). ### Claim 2 (depends on 1) The method of claim 1, wherein the stream of data includes a stream of video data having a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme. ### Claim 3 (depends on 1) The method of claim 1, wherein the maximum number of retransmissions varies based on the second TID field value. ### Claim 4 (depends on 1) The method of claim 1, further comprising: performing deep packet inspection to retrieve the DSCP field value of the MPDU and provide the retransmission policy to the MPDU. ### Claim 5 (depends on 1) The method of claim 1, further comprising: prioritizing the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value based on an IP Precedence portion of the DSCP field value of the MPDU. ### Claim 6 (depends on 1) The method of claim 1, further comprising: providing the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU. ### Claim 7 (depends on 1) The method of claim 1, further comprising: determining that the DSCP field value of the MPDU is a Class Selector Code Point value; interpreting the Class Selector Code Point value as a User Priority value; prioritizing the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and providing the retransmission policy to the MPDU based on an IP Precedence portion of the DSCP field value of the MPDU. ### Claim 8 (depends on 1) The method of claim 1, further comprising: determining that the DSCP field value of the MPDU is a Non-class Selector Code Point value; prioritizing the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value selected based on the Non-class Selector Code Point value; and providing the retransmission policy to the MPDU based on the Non-class Selector Code Point value. ### Claim 9 (depends on 1) The method of claim 1, further comprising: determining that the DSCP field value of the MPDU is a Non-class Selector Code Point value; interpreting an IP Precedence portion of the DSCP field value as a User Priority value; prioritizing the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and providing the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU. ### Claim 10 (depends on 1) The method of claim 1, wherein the MPDU includes the first TID field value, and wherein the second TID field value is based on the DSCP field value. ### Claim 11 (depends on 10) The method of claim 10, wherein the second TID value determines the retransmission policy of the MPDU. ### Claim 12 (depends on 11) The method of claim 11, wherein the second TID field value has a value between eight (8) and fifteen (15) when Hybrid Coordination Function Controlled Channel Access (HCCA) is disabled between the access point and the destination station. ### Claim 13 (depends on 1) The method of claim 1, wherein the DSCP field value is associated with a Network Layer and the MPDU is associated with a Data Link Layer. ### Claim 14 (depends on 1) The method of claim 1, wherein the DSCP field value is defined in a payload portion of the MPDU. ### Claim 15 (depends on 1) The method of claim 1, wherein providing the retransmission policy to the MPDU based on the DSCP field value is defined on a per MPDU basis. ### Claim 16 An access point in communication with a destination station, the access point comprising: a wireless communication interface operative to communicate with a wireless local area network (WLAN); and a processing circuit coupled to the wireless communication interface and adapted to: receive a stream of data including at least one media access control protocol data unit (MPDU) having a Differentiated Services Code Point (DSCP) field value, wherein the stream of data has a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme; provide a retransmission policy to the MPDU based on the DSCP field value by replacing a first Traffic Identifier (TID) field value with a second TID field value, wherein the retransmission policy identifies a maximum number of retransmissions of the MPDU to the destination station; and transmit the MPDU to the destination station via the WLAN. ### Claim 17 (depends on 16) The access point of claim 16, wherein the stream of data includes a stream of video data having a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme. ### Claim 18 (depends on 16) The access point of claim 16, wherein the processing circuit is further adapted to: perform deep packet inspection to retrieve the DSCP field value of the MPDU and provide the retransmission policy to the MPDU. ### Claim 19 (depends on 16) The access point of claim 16, wherein the processing circuit is further adapted to: prioritize the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value based on an IP Precedence portion of the DSCP field value of the MPDU; and provide the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU. ### Claim 20 (depends on 16) The access point of claim 16, wherein the processing circuit is further adapted to: determine that the DSCP field value of the MPDU is a Class Selector Code Point value; interpret the Class Selector Code Point value as a User Priority value; prioritize the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and provide the retransmission policy to the MPDU based on an IP Precedence portion of the DSCP field value of the MPDU. ### Claim 21 (depends on 16) The access point of claim 16, wherein the processing circuit is further adapted to: determine that the DSCP field value of the MPDU is a Non-class Selector Code Point value; prioritize the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value selected based on the Non-class Selector Code Point value; and provide the retransmission policy to the MPDU based on the Non-class Selector Code Point value. ### Claim 22 (depends on 16) The access point of claim 16, wherein the processing circuit is further adapted to: determine that the DSCP field value of the MPDU is a Non-class Selector Code Point value; interpret an IP Precedence portion of the DSCP field value as a User Priority value; prioritize the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and provide the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU. ### Claim 23 An access point in communication with a destination station, the access point comprising: means for receiving a stream of data including at least one media access control protocol data unit (MPDU) having a Differentiated Services Code Point (DSCP) field value, wherein the stream of data has a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme; means for providing a retransmission policy to the MPDU based on the DSCP field value by replacing a first Traffic Identifier (TID) field value with a second TID field value, wherein the retransmission policy identifies a maximum number of retransmissions of the MPDU to the destination station; and means for transmitting the MPDU to the destination station via a wireless local area network (WLAN). ### Claim 24 (depends on 23) The access point of claim 23, wherein the stream of data includes a stream of video data having a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme. ### Claim 25 (depends on 23) The access point of claim 23, further comprising: means for performing deep packet inspection to retrieve the DSCP field value of the MPDU and provide the retransmission policy to the MPDU. ### Claim 26 (depends on 23) The access point of claim 23, further comprising: means for prioritizing the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value based on an IP Precedence portion of the DSCP field value of the MPDU; and means for providing the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU. ### Claim 27 (depends on 23) The access point of claim 23, further comprising: means for determining that the DSCP field value of the MPDU is a Class Selector Code Point value; means for interpreting the Class Selector Code Point value as a User Priority value; means for prioritizing the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and means for providing the retransmission policy to the MPDU based on an IP Precedence portion of the DSCP field value of the MPDU. ### Claim 28 (depends on 23) The access point of claim 23, further comprising: means for determining that the DSCP field value of the MPDU is a Non-class Selector Code Point value; means for prioritizing the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value selected based on the Non-class Selector Code Point value; and means for providing the retransmission policy to the MPDU based on the Non-class Selector Code Point value. ### Claim 29 (depends on 23) The access point of claim 23, further comprising: means for determining that the DSCP field value of the MPDU is a Non-class Selector Code Point value; means for interpreting an IP Precedence portion of the DSCP field value as a User Priority value; means for prioritizing the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and means for providing the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU. ### Claim 30 A non-transitory processor-readable medium having one or more instructions operational at an access point in communication with a destination station, which when executed by at least one processor causes the processor to: receive a stream of data including at least one media access control protocol data unit (MPDU) having a Differentiated Services Code Point (DSCP) field value, wherein the stream of data has a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme; provide a retransmission policy to the MPDU based on the DSCP field value by replacing a first Traffic Identifier (TID) field value with a second TID field value, wherein the retransmission policy identifies a maximum number of retransmissions of the MPDU to the destination station; and transmit the MPDU to the destination station via a wireless local area network (WLAN). ### Claim 31 (depends on 30) The non-transitory processor-readable medium of claim 30, wherein the stream of data includes a stream of video data having a layered modulation scheme, the DSCP field value of the MPDU identifying at least one layer of the layered modulation scheme. ### Claim 32 (depends on 30) The non-transitory processor-readable medium of claim 30, having further instructions which when executed by the processor causes the processor to: perform deep packet inspection to retrieve the DSCP field value of the MPDU and provide the retransmission policy to the MPDU. ### Claim 33 (depends on 30) The non-transitory processor-readable medium of claim 30, having further instructions which when executed by the processor causes the processor to: prioritize the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value based on an IP Precedence portion of the DSCP field value of the MPDU; and provide the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU. ### Claim 34 (depends on 30) The non-transitory processor-readable medium of claim 30, having further instructions which when executed by the processor causes the processor to: determine that the DSCP field value of the MPDU is a Class Selector Code Point value; interpret the Class Selector Code Point value as a User Priority value; prioritize the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and provide the retransmission policy to the MPDU based on an IP Precedence portion of the DSCP field value of the MPDU. ### Claim 35 (depends on 30) The non-transitory processor-readable medium of claim 30, having further instructions which when executed by the processor causes the processor to: determine that the DSCP field value of the MPDU is a Non-class Selector Code Point value; prioritize the transmission of the MPDU to the destination station according to an Access Category value, the Access Category value selected based on the Non-class Selector Code Point value; and provide the retransmission policy to the MPDU based on the Non-class Selector Code Point value. ### Claim 36 (depends on 30) The non-transitory processor-readable medium of claim 30, having further instructions which when executed by the processor causes the processor to: determine that the DSCP field value of the MPDU is a Non-class Selector Code Point value; interpret an IP Precedence portion of the DSCP field value as a User Priority value; prioritize the transmission of the MPDU to the destination station according to an Access Category associated with the User Priority value; and provide the retransmission policy to the MPDU based on a Non-IP Precedence portion of the DSCP field value of the MPDU.