Response to an Amendment
This office action is a response to a communication made on 12/10/2025.
Claims 1-27 are canceled.
Claims 28-42 are pending for this application.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 09/04/2025 and 03/31/2026 were filed before the mailing date of the final action on 05/14/2026. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Response to Arguments
Applicant: Applicant arguments, see remarks on page 7-10, filed 12/10/2025, applicant argues that, “Johansson does not explicitly teach the limitation of receiving from the second network node an assistance information protocol data unit (PDU) comprising an indication of a proportion of packets within a downlink user plane flow over the downlink connection that are to be marked with a congestion indicator” recited in claims 28, 33, 38 and 41.
Examiner: Applicant's arguments filed 12/10/2025 have been fully considered but they are not persuasive. Examiner respectfully disagrees.
Johansson teaches receiving from the second network node an assistance information protocol data unit (PDU) comprising an indication of a proportion of packets within a downlink user plane flow over the downlink connection that are to be marked with a congestion indicator because Fig. 2, teaches the Flow Control (FC) specified over the F1-U interface between the DU and CU-UP also will be supported by the IAB node towards the CU-UP in the IAB-donor. This flow control could help support varying throughput towards between the IAB node and UE over a radio interface, Fig. 9, page-5, II. 25-30, page-6, II. 5-8, teaches F1-U protocol data as protocol data unit… receive report, from second radio network node, wherein report comprises information that congestion has been detected in first radio network node… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount (i.e. proportion of packets) of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream [i.e. although the report is being prepared by the second network node, the marking a proportion of packets within a downlink user plane is being performed at the first node itself], page-11, II. 32-35, page-6, II. 1-8, teaches the second radio network node 132 receives the marked packet and reports back to the central network node 12 using e.g. a report, such as a FC report (i.e. assistance information protocol data unit (PDU). The report may include information about one or more packet has exceeded the threshold of delay, indicate a volume of received data packets (bytes) with said indication of threshold exceeded, which node has marked the packets, that resource availability (resource blocks) is becoming scarce at the first radio network node 131, in case of several congested radio network nodes on an end-to-end path, an indication of the first radio network node 131 that experiences the delay on the path or a list of nodes experiencing the delay on the end-to-end path. Thus the report may give information about the congestion level in the form of how often a target delay has been exceeded, counted either in number of marked packets or as a volume of received packets (bytes) that was marked.
Applicant: Applicant arguments, see remarks on page 10-11, filed 12/10/2025, applicant argues that, “Johansson does not explicitly teach the limitation of “the indication of the proportion of packets that are to be marked explicitly states the proportion of packets that are to be marked” recited ion claims 30 and 40.
Examiner: Applicant's arguments filed 12/10/2025 have been fully considered but they are not persuasive. Examiner respectfully disagrees.
Johansson teaches the indication of the proportion of packets that are to be marked explicitly states the proportion of packets that are to be marked because Fig. 2, Fig. 9, page-5, II. 25-30, page-6, II. 5-8, teaches F1-U protocol data as protocol data unit… receive report, from second radio network node, wherein report comprises information that congestion has been detected in first radio network node… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag (i.e. explicit indication), in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount (i.e. proportion of packets) of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream.
Applicant: Applicant arguments, see remarks on page 11, filed 12/10/2025, applicant argues that, “Johansson does not explicitly teach the limitation of “wherein the first network node comprises a centralized unit of a base station and the second network node comprises a distributed unit of the base station” recited in claims 32 and 37.
Examiner: Applicant's arguments filed 12/10/2025 have been fully considered but they are not persuasive. Examiner respectfully disagrees.
Johansson teaches wherein the first network node comprises a centralized unit of a base station and the second network node comprises a distributed unit of the base station because see Fig. 2-3, page-2, II. 30, teaches gNB-Central Unit (CU) as centralized unit in first network node, and gNB-Distributed Unit (DU) as distributed unit in second network node, page-23, II. 1, teaches sending a flow control report e.g. to a central unit (CU).
Applicant: Applicant arguments, see remarks on page 11, filed 12/10/2025, applicant argues that, “Johansson does not explicitly teaches the limitation of “wherein the indication of a proportion of packets within the downlink user plane flow over the downlink connection that are to be marked with a congestion indicator also indicates a probability with which the first network node is to mark packets of the downlink user plane flow with the congestion indicator” recited in claim 35.
Examiner: Applicant's arguments filed 12/10/2025 have been fully considered but they are not persuasive. Examiner respectfully disagrees.
Johansson teaches wherein the indication of a proportion of packets within the downlink user plane flow over the downlink connection that are to be marked with a congestion indicator also indicates a probability with which the first network node is to mark packets of the downlink user plane flow with the congestion indicator because Fig. 9, page-5, II. 25-30, page-6, II. 5-8, and page-12, II. 24-35, teaches receive report, from second radio network node, wherein report comprises information that congestion has been detected in first radio network node… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream… the marked data packet would travel all the way to its destination IAB node, which may then feed this information to the IAB-donor CU, indicating on which flow(s) the congestion has occurred or is likely (i.e. probability) to occur… setting a threshold significantly lower than a typical queuing delay experienced at congestion seems plausible. Namely, setting a low threshold implies keeping the buffer fill rate at a low level, thus enabling reducing the probability of sudden congestion.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 28, 30-38, and 40-42 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Johansson et al. (WO 2020/159416), hereinafter “Johansson”. Johansson cited in applicant IDS filed 03/19/2024. An English translation has been added with this application.
With respect to claim 28, Johansson discloses a method performed by a first network node for downlink congestion control in a radio network (Fig. 6, step 601, teaches detect congestion over a link, page-5, II. 20-24, teaches a method performed by a first radio network node, such as a relay node also denoted as IAB node, for handling data packets or handling communication in a wireless communications network, wherein the wireless communications network comprises the first radio network node and a second radio network node relaying data packets between a central network node and a UE), the first network node handling one or more first layers of a protocol stack, wherein the one or more first layers comprise a packet data convergence protocol (PDCP) layer (page-4, II. 1-4, teaches Transport Network Layer (TNL) in order to allow FC of user data packets transferred from the node hosting the NR Packet Data Convergence Protocol (PDCP) as protocol stack, e.g. CU-UP in the case of CU-DU split, to the corresponding node, i.e. the DU), and, for a downlink connection between the radio network and a wireless device (page-1, II. 22, teaches the radio network node communicates over a downlink (DL) to the UE, page-5, II.25-27, teaches the first radio network node detects congestion over a link towards the second radio network node e.g. a data packet experiences a delay above a threshold), the first network node being communicatively coupled to a second network node handling one or more second layers of the protocol stack for the downlink connection (page-3, II. 33-35, page-5, II. 20-24, teaches RLC means Radio Link Control protocol, MAC means Medium Access Control, and PHY means physical layer as second layers of the protocol stack….a method performed by a first radio network node, such as a relay node also denoted as IAB node, for handling data packets or handling communication in a wireless communications network, wherein the wireless communications network comprises the first radio network node and a second radio network node relaying data packets between a central network node and a UE), wherein the one or more second layers are lower than the one or more first layers (see Fig. 2, page-4, II. 1-4, and page-3, II. 33-35, teaches PDCP is located in the CU-UP, while RLC and lower layer functionality MAC and PHY layers are located in the DU) the method comprising:
receiving from the second network node an assistance information protocol data unit (PDU) comprising an indication of a proportion of packets within a downlink user plane flow over the downlink connection that are to be marked with a congestion indicator (Fig. 2, teaches the Flow Control (FC) specified over the F1-U interface between the DU and CU-UP also will be supported by the IAB node towards the CU-UP in the IAB-donor. This flow control could help support varying throughput towards between the IAB node and UE over a radio interface, Fig. 9, page-5, II. 25-30, page-6, II. 5-8, teaches F1-U protocol data as protocol data unit… receive report, from second radio network node, wherein report comprises information that congestion has been detected in first radio network node… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream [i.e. although the report is being prepared by the second network node, the marking a proportion of packets within a downlink user plane is being performed at the first node itself], page-11, II. 32-35, page-6, II. 1-8, teaches the second radio network node 132 receives the marked packet and reports back to the central network node 12 using e.g. a report, such as a FC report (i.e. assistance information protocol data unit (PDU). The report may include information about one or more packet has exceeded the threshold of delay, indicate a volume of received data packets (bytes) with said indication of threshold exceeded, which node has marked the packets, that resource availability (resource blocks) is becoming scarce at the first radio network node 131, in case of several congested radio network nodes on an end-to-end path, an indication of the first radio network node 131 that experiences the delay on the path or a list of nodes experiencing the delay on the end-to-end path. Thus the report may give information about the congestion level in the form of how often a target delay has been exceeded, counted either in number of marked packets or as a volume of received packets (bytes) that was marked), wherein the proportion is based on a delay experienced by packets of the downlink user plane flow sent by the second network node to the wireless device (page-5, II. 25-30, page-6, II. 5-8, page 12, II. 2-9, teaches the first radio network node detects congestion over a link towards the second radio network node e.g. a data packet experiences a delay above a threshold. Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet and transmits the data packet towards the second radio network node…the report may include more detailed information that quantifies the amount (i.e. proportion) of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream… in case of several congested radio network nodes on an end-to-end path, an indication of the first radio network node 131 that experiences the delay on the path or a list of nodes experiencing the delay on the end-to-end path. Thus, the report may give information about the congestion level in the form of how often a target delay has been exceeded, counted either in number of marked packets or as a volume of received packets (bytes) that was marked);
marking the proportion of packets with the congestion indicator (See Fig. 6-10, page-5, II. 25-30, page-6, II. 2-4, teaches the first radio network node detects congestion over a link towards the second radio network node e.g. a data packet experiences a delay above a threshold. Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet and transmits the data packet towards the second radio network node… the second radio network node receives one or more data packets with marking indicating congestion at the first radio network node.); and
transmitting packets for the downlink user plane flow to the second network node for onward transmission to the wireless device (See Fig. 6-10, page-5, II. 25-30, teaches the first radio network node detects congestion over a link towards the second radio network node e.g. a data packet experiences a delay above a threshold. Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet and transmits the data packet towards the second radio network node).
For claim 38, it is an apparatus claim corresponding to the method of claim 28. Therefore claim 38 is rejected under the same ground as claim 28.
With respect to claim 33, Johansson discloses a method performed by a second network node for downlink congestion control in a radio network (page-6, II. 34-35 and page-7, II. 1-3, page-10, II. 28-29, page-11, II. 25-27, teaches providing a second radio network node, such as a relay node also denoted as IAB node, for handling data packets or handling communication in a wireless communications network, wherein the wireless communications network comprises a first radio network node and the second radio network node relaying data packets between a central network node and a UE… The second radio network node 132 may be an IAB node e.g. a radio remote unit (RRU)… indicate to the central network node 12 such as a IAB-donor CU which data flows are responsible for the congestion, in order for the network node to take the right actions.), the second network node handling one or more second layers of a protocol stack for a downlink connection between a radio network and a wireless device (see Fig. 6-10, page-3, II. 22-23, teaches the DU function of IAB nodes is identical to the function of a gNB-DU [thus, clearly second network node may also be a gNB -Distributed Unit (DU) node, which implements one or more second layers of the protocol stack for the downlink connection], the second network node being communicatively coupled to a first network node handling one or more first layers of the protocol stack for the downlink connection (page-4, II. 1-4, page-10, II. 28-29, teaches Transport Network Layer (TNL) in order to allow FC of user data packets transferred from the node hosting the NR Packet Data Convergence Protocol (PDCP) as protocol stack, e.g. CU-UP in the case of CU-DU split, to the corresponding node, i.e. the DU… The second radio network node 132 may be an IAB node e.g. a radio remote unit (RRU)), wherein the one or more first layers comprise a packet data convergence protocol (PDCP) layer (page-4, II. 1-4, teaches Transport Network Layer (TNL) in order to allow FC of user data packets transferred from the node hosting the NR Packet Data Convergence Protocol (PDCP) as protocol stack), and wherein the one or more second layers are lower than the one or more first layers (see Fig. 2, page-4, II. 1-4, and page-3, II. 33-35, teaches PDCP is located in the CU-UP, while RLC and lower layer functionality MAC and PHY layers are located in the DU), the method comprising:
receiving, from the first network node, packets for a downlink user plane flow over the downlink connection, for onward transmission to the wireless device (Fig. 6-10, page-7, II. 4-7, teaches receive data packet carrying marking from first radio network node indicating that congestion is detected in first radio network node…receive a data packet carrying a marking, from a first radio network node. The second radio network node is further configured to transmit a report, to the central network node, wherein the report comprises information that congestion has been detected in the first radio network node.); and
sending, to the first network node an assistance information protocol data unit (PDU) comprising an indication of a proportion of packets within the downlink user plane flow over the downlink connection that are to be marked with a congestion indicator (Fig. 2, page-12, II. 18-19, page-5, II. 25-30, page-6, II. 5-8, teaches F1-U protocol data as protocol data unit… transmit a command controlling rate or reducing a flow related to the first radio network node 131… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream [i.e. although the report is being prepared by the second network node, the marking a proportion of packets within a downlink user plane is being performed at the first node itself], wherein the proportion is based on a delay experienced by packets of the downlink user plane flow sent by the second network node to the wireless device (page-5, II. 25-30, page-6, II. 5-8, page 12, II. 2-9, teaches the first radio network node detects congestion over a link towards the second radio network node e.g. a data packet experiences a delay above a threshold. Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet and transmits the data packet towards the second radio network node…the report may include more detailed information that quantifies the amount (i.e. proportion) of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream… in case of several congested radio network nodes on an end-to-end path, an indication of the first radio network node 131 that experiences the delay on the path or a list of nodes experiencing the delay on the end-to-end path. Thus, the report may give information about the congestion level in the form of how often a target delay has been exceeded, counted either in number of marked packets or as a volume of received packets (bytes) that was marked).
For claim 41, it is an apparatus claim corresponding to the method of claim 33. Therefore claim 41 is rejected under the same ground as claim 33.
With respect to claims 30 and 40, Johansson discloses the method of claim 28, wherein the indication of the proportion of packets that are to be marked explicitly states the proportion of packets that are to be marked (Johansson, Fig. 2, Fig. 9, page-5, II. 25-30, page-6, II. 5-8, teaches F1-U protocol data as protocol data unit… receive report, from second radio network node, wherein report comprises information that congestion has been detected in first radio network node… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag (i.e. explicit indication), in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount (i.e. proportion of packets) of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream).
With respect to claims 31 and 36, Johansson discloses the method of claim 28, wherein the one or more second layers comprise one or more of: a radio link control (RLC) layer; a medium access control (MAC) layer; and a physical (PHY) layer (Johansson, see Fig. 2, page-3, II. 33-35, teaches RLC means Radio Link Control protocol, MAC means Medium Access Control, and PHY means physical layer are second layers).
With respect to claims 32 and 37, Johansson discloses the method of claim 28, wherein the first network node comprises a centralized unit of a base station and the second network node comprises a distributed unit of the base station (Johansson, See Fig. 2-3, page-2, II. 30, teaches gNB-Central Unit (CU) as centralized unit in first network node, and gNB-Distributed Unit (DU) as distributed unit in second network node).
With respect to claims 34 and 42, Johansson discloses the method of claim 33, wherein the indication of a proportion of packets within the downlink user plane flow over the downlink connection that are to be marked with a congestion indicator, is an explicit indication (Johansson, Fig. 2, Fig. 9, page-5, II. 25-30, page-6, II. 5-8, teaches F1-U protocol data as protocol data unit… receive report, from second radio network node, wherein report comprises information that congestion has been detected in first radio network node… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag (i.e. explicit indication), in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream).
With respect to claim 35, Johansson discloses the method of claim 33, wherein the indication of a proportion of packets within the downlink user plane flow over the downlink connection that are to be marked with a congestion indicator also indicates a probability with which the first network node is to mark packets of the downlink user plane flow with the congestion indicator (Johansson, Fig. 9, page-5, II. 25-30, page-6, II. 5-8, and page-12, II. 24-35, teaches receive report, from second radio network node, wherein report comprises information that congestion has been detected in first radio network node… Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet, the report may include more detailed information that quantifies the amount of congestion, such as e.g. the number of marked bytes during the period between two reports. By comparing the number of marked bytes with the number of bytes sent downstream… the marked data packet would travel all the way to its destination IAB node, which may then feed this information to the IAB-donor CU, indicating on which flow(s) the congestion has occurred or is likely (i.e. probability) to occur… setting a threshold significantly lower than a typical queuing delay experienced at congestion seems plausible. Namely, setting a low threshold implies keeping the buffer fill rate at a low level, thus enabling reducing the probability of sudden congestion).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 29 and 39 is/are rejected under 35 U.S.C. 103 as being unpatentable over Johansson et al. (WO 2020/159416), hereinafter “Johansson” in view of Lundqvist et al. (US 2017/0187641), hereinafter “Lundqvist”. Lundqvist cited in applicant IDS filed 03/19/2024.
With respect to claims 29 and 39, Johansson discloses the method of claim 28, Johansson See Fig. 6-10, page-5, II. 25-30, page-6, II. 2-4, teaches the first radio network node detects congestion over a link towards the second radio network node e.g. a data packet experiences a delay above a threshold. Upon detection of the congestion the first radio network node adds a marking e.g. sets a flag, in a header such as an adaptation layer header in a data packet and transmits the data packet towards the second radio network node… the second radio network node receives one or more data packets with marking indicating congestion at the first radio network node. However, Johansson remain silent on wherein the marking the proportion of packets with the congestion indicator is performed by setting Explicit Congestion Notification (ECN) bits in the IP header of the packets.
Lundqvist discloses wherein the marking the proportion of packets with the congestion indicator is performed by setting Explicit Congestion Notification (ECN) bits in the IP header of the packets (¶0145, teaches The AQM applies rules to mark data packets with Congestion Experienced (CE), which is part of the Explicit Congestion Notification (ECN) bits in the IP header, ¶0169, teaches one explicit congestion marking, e.g. ECN marking, will be applied according to a function of the congestion level of the shared communication resources of all the plurality of queues (first marking), but not as a function of each separate queue (second marking or dropping of data packets).
Therefore, it would be obvious to one of ordinary skill in the art before the effective filing date of the invention to modify Johansson’s marking e.g. sets a flag, in a header with Explicit Congestion Notification (ECN) bits in the IP header of the packets of Lundqvist, in order to enable endpoints to respond intelligently without dropping packets and degrading performance (Lundqvist, ¶0096).
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to GOLAM MAHMUD whose telephone number is (571)270-0385. The examiner can normally be reached Mon-Fri 8.00-5.00pm.
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/GOLAM MAHMUD/ Examiner, Art Unit 2458/UMAR CHEEMA/Supervisory Patent Examiner, Art Unit 2458
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