US-12621709-B2 - Systems and methods for explicit congestion notification in a radio access network

Abstract

A device may include a processor configured to monitor a data flow, associated with a user equipment (UE) device, in a Radio Access Network (RAN). The processor may be further configured to detect a congestion condition for the monitored data flow associated with the UE device; generate an Explicit Congestion Notification (ECN) in response to detecting the congestion condition; and mark packets associated with the data flow with the generated ECN.

Inventors

• Jin Yang
• Wei David Huang
• Gerardo S. Libunao

Assignees

• VERIZON PATENT AND LICENSING INC.

Dates

Publication Date

20260505

Application Date

20230906

Claims (20)

1. 1 . A method comprising: monitoring, by a device, a data flow associated with a user equipment (UE) device in a Radio Access Network (RAN); detecting, by the device, a congestion condition for the monitored data flow associated with the UE device; generating, by the device, an Explicit Congestion Notification (ECN) in response to detecting the congestion condition; and marking, by the device, packets associated with the data flow with the generated ECN, wherein the marking includes marking packets travelling in an opposite direction to packets travelling a direction for which the congestion condition is detected.
2. 2 . The method of claim 1 , wherein the device includes a Centralized Unit (CU) in the RAN, and wherein detecting the congestion condition for the monitored data flow associated with the UE device includes: receiving a congestion notification for the monitored data flow from a Distributed Unit (DU) in the RAN via an F1 interface.
3. 3 . The method of claim 2 , wherein the congestion notification includes an indication that a signal strength or quality parameter value for wireless signals, for the monitored data flow associated with the UE device, is below a signal strength or quality threshold.
4. 4 . The method of claim 3 , wherein the signal strength or quality parameter value includes a Channel Quality Indicator (CQI) value.
5. 5 . The method of claim 3 , wherein the congestion notification further includes an indication that the signal strength or quality parameter value has been below the signal strength or quality threshold for at least a threshold length of time.
6. 6 . The method of claim 2 , wherein the congestion notification includes an indication that a loading parameter value for a base station associated with the UE device is above a loading threshold.
7. 7 . The method of claim 6 , wherein the loading parameter value includes a Physical Resource Block (PRB) utilization rate value.
8. 8 . The method of claim 2 , further comprising: receiving another notification, from the DU via the F1 interface, wherein the other notification indicates that the congestion condition has ceased to exist for at least a threshold length of time; and ceasing to mark packets associated with the data flow with the generated ECN.
9. 9 . The method of claim 1 , wherein marking the packets associated with the data flow with the generated ECN includes: marking packet headers with the generated ECN using Packet Data Convergence Protocol (PDCP).
10. 10 . The method of claim 1 , wherein detecting the congestion condition for the monitored data flow associated with the UE device includes: determining that a buffer level associated with the monitored data flow has exceeded a buffer threshold.
11. 11 . A device comprising: a processor configured to: monitor a data flow, associated with a user equipment (UE) device, in a Radio Access Network (RAN); detect a congestion condition for the monitored data flow associated with the UE device; generate an Explicit Congestion Notification (ECN) in response to detecting the congestion condition; and mark packets associated with the data flow with the generated ECN, wherein the processor configured to mark the packets is configured to mark packets travelling in an opposite direction to packets travelling a direction for which the congestion condition is detected.
12. 12 . The device of claim 11 , wherein the device includes a Centralized Unit (CU) in the RAN, and wherein, when detecting the congestion condition for the monitored data flow associated with the UE device, the processor is further configured to: receive a congestion notification for the monitored data flow from a Distributed Unit (DU) in the RAN via an F1 interface.
13. 13 . The device of claim 12 , wherein the congestion notification includes an indication that a signal strength or quality parameter value for wireless signals, for the monitored data flow associated with the UE device, has been below a signal strength or quality threshold for at least a threshold length of time.
14. 14 . The device of claim 12 , wherein the congestion notification includes an indication that a loading parameter value for a base station associated with the UE device is above a loading threshold.
15. 15 . The device of claim 12 , wherein the processor is further configured to: receive another notification, from the DU via the F1 interface, wherein the other notification indicates that the congestion condition has ceased to exist for at least a threshold length of time; and cease to mark packets associated with the data flow with the generated ECN.
16. 16 . The device of claim 11 , wherein, when marking the packets associated with the data flow with the generated ECN, the processor is further configured to: mark packet headers with the generated ECN using Packet Data Convergence Protocol (PDCP).
17. 17 . The device of claim 11 , wherein, when detecting the congestion condition for the monitored data flow associated with the UE device, the processor is further configured to: determine that a buffer level associated with the monitored data flow has exceeded a buffer threshold.
18. 18 . A system comprising: a Centralized Unit (CU) in a Radio Access Network (RAN) configured to: monitor a data flow, associated with a user equipment (UE) device, in the RAN; detect a congestion condition for the monitored data flow associated with the UE device; generate an Explicit Congestion Notification (ECN) in response to detecting the congestion condition; and mark packets associated with the data flow with the generated ECN, wherein the processor configured to mark the packets is configured to mark packets travelling in an opposite direction to packets travelling a direction for which the congestion condition is detected; and a Distributed Unit (DU) in the RAN configured to: send a congestion notification for the monitored data flow to the CU via an F1 interface, wherein the CU is configured to detect the congestion condition for the monitored data flow associated with the UE device based on the congestion notification.
19. 19 . The system of claim 18 , wherein the congestion notification includes an indication that a signal strength or quality parameter value for wireless signals, for the monitored data flow associated with the UE device, has been below a signal strength or quality threshold for at least a threshold length of time.
20. 20 . The system of claim 18 , wherein the congestion notification includes an indication that a loading parameter value for a base station associated with the UE device is above a loading threshold.

Description

BACKGROUND INFORMATION To satisfy the needs and demands of users of mobile communication devices, providers of wireless communication services continue to improve and expand their networks. One aspect of such improvements includes the development of wireless access networks and options to utilize such wireless access networks. A provider may operate a wireless access network that manages a large number of user devices using different types of services under varying conditions. Managing different types of services under varying conditions poses various challenges. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an environment according to an implementation described herein; FIG. 2 illustrates exemplary components of a Radio Access Network (RAN) according to an implementation described herein; FIG. 3 illustrates exemplary components of device that may be included in a component of an environment according to an implementation described herein; FIG. 4 illustrates exemplary components of a Distributed Unit and a Centralized Unit according to an implementation described herein; FIG. 5 illustrates exemplary components of a sessions database according to an implementation described herein; FIG. 6 illustrates a flowchart for performing Explicit Congestion Notification (ECN) marking in a RAN according to an implementation described herein; and FIGS. 7A and 7B illustrate exemplary signal flows according to an implementation described herein. DETAILED DESCRIPTION OF EMBODIMENTS The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. A cellular wireless network enables user equipment (UE) devices to connect to networks via a Radio Access Network (RAN) and a core network in order to communicate with other devices connected to the RAN, communicate with devices in other networks, access applications or services hosted by a provider in the core network, and/or make use of other types of communication services. For example, a UE device may use enhanced Mobile Broadband (eMBB) services for Voice over Internet Protocol (VoIP) telephone calls and/or data sessions for accessing Internet websites, use massive Internet of Things (IoT) communication as an IoT device, use Ultra-Reliable Low Latency Communication (URLLC) for mission critical low latency communication, etc. Each type of communication service may be associated with a different set of requirements. In order to establish a communication session, a UE device may establish a Protocol Data Unit (PDU) session in the core network via the RAN. The UE device may then establish one or more data flows in the PDU session. Each data flow may be associated with a Quality of Service (QoS) and/or other types of service requirements. Conditions associated with a data flow in a wireless network may vary. For example, a UE device may move from an area with good signal coverage to an area with poor signal coverage, resulting in a decrease in signal strength and/or signal quality. As another example, a base station may experience an increase in traffic load, resulting in an increase in signal latency. Changes in the conditions associated with a data flow in a wireless network may result in a congestion condition. A congestion condition may prevent the service requirements associated with the data flow to be satisfied. A UE device may provide a congestion notification using an Over-The-Top (OTT) notification. For example, an application running on the UE device may detect a decrease in throughput or an increase in a packet drop rate and/or packet error rate, and, in response, send a notification to an application server associated with the application that the application is experiencing a congestion condition. However, an OTT notification may be too slow to enable the application server to adjust to a congestion condition in an efficient manner. For example, the conditions of a wireless connection may be subject to high variability and an OTT notification may be received by the application server after the conditions have already changed, resulting in slow adaptation of the data rate for the data flow by the application server. Thus, OTT congestion notifications may be too slow for applications that may benefit from a rapid rate adaptation, such as live video applications, extended reality (XR) applications, etc. A more efficient congestion notification mechanism includes the use of an Explicit Congestion Notification (ECN). Traditionally, Transmission Control Protocol (TCP) and/or Internet Protocol (IP) networks signal congestion by dropping packets. ECN enables congestion notification without dropping packets. An ECN, implemented as part of a Low Latency, Low Loss, and Scalable Throughput (L4S) Internet service, corresponds to setting a field, in a packet header, which indicates a congestion condition is present. Therefore, if the ECN field (or ECN bits in a particular field of a