A method and system for deep integration of on-board UPF and user plane of 5G base stations

Abstract

The present invention discloses a method and system for deep integration of the on-satellite UPF and the user plane of a 5G base station, including: deeply integrating the 5G base station module with the core network user plane network element UPF and receiving data packets, where both the 5G base station module and the UPF are on the satellite; when the data packet is an on-satellite local service, the deeply integrated 5G base station module and UPF forward the data packet through an inter-satellite link; when the data packet is a non-on-satellite local service, the deeply integrated 5G base station module and UPF forward the data packet to the ground UPF through a feeder link. By deeply integrating the base station and the UPF, the present invention cancels the N3 interface between the base station and the UPF, and there is no need to frequently perform GTP-U packet encapsulation, decapsulation, unpacking, and repackaging operations for the user's uplink and downlink data packets, effectively reducing the computing power overhead of the satellite platform, reducing the packet processing delay, and effectively reducing the routing and switching backplane bandwidth of the satellite platform.

Description

Technical Field

[0001] The present invention relates to the field of inter-satellite routing and forwarding, and particularly to a method and system for deep integration of on-satellite UPF and the user plane of 5G base stations. Background Art

[0002] With the development of low Earth orbit (LEO) satellite communication technology, the technical capabilities of satellite communication have been enhanced, and the use cases and services of satellite communication have been enriched. Discussions and attempts on the integration of satellites and terrestrial mobile communications have never stopped. With the increasing maturity of 5G technology, standardization organizations including 3GPP and ITU have started to study the standardization issues of satellite-terrestrial integration. 3GPP has carried out research on the NTN satellite mobile communication system based on 5G technology in Releases 15 and 16, plans to release the first satellite communication standard adopting the 5G terrestrial cellular system standard specification in Release 17, and plans to initiate research and standardization on on-satellite regeneration technology in Release 18. ITU has proposed four application scenarios for satellite-terrestrial 5G integration, supporting research on key issues such as intelligent routing, dynamic cache management for consistent quality of service, network function virtualization (NFV) / software-defined network (SDN). In June 2017, 16 organizations including BT established the Sat5G Alliance in ETSI to study satellite and terrestrial 5G integration technology. In countries where 6G research has started earlier, such as China, South Korea, the European Union, and Japan, the future 6G support for an integrated space-ground network is taken as the core technical goal.

[0003] According to the ITU protocol description, a fixed, mobile, and satellite integrated network architecture will be formed in the future. In the satellite-based integrated network framework, all or part of the functions of the access network and the core network will be transplanted to on-satellite processing. Combining the future vision of the integrated space-ground communication network by the Future Mobile Forum, in the overall architecture concept, LEO satellites will play more roles in access and edge core networks. The core network is distributed and consists of an edge core network deployed at non-terrestrial network nodes and a cloud core network deployed at terrestrial nodes. The edge core network and the cloud core network achieve edge-cloud collaboration through computing power scheduling.

[0004] Due to the limited resources of satellite nodes, after the UPF is deployed on the satellite, it will inevitably increase the resource consumption of the board, especially the user plane, which puts higher requirements on the computing power and data packet forwarding ability of the satellite. The N3 interface is the interface between the NG RAN and the UPF, and uses the GTP-U protocol to tunnel user data between the NG RAN and the UPF. The N3 interface uses the GTP-U / UDP / IP protocol stack. In the existing technology, when the base station side, the UPF side, and the satellite platform side process uplink and downlink data, each data packet needs to be encapsulated or decapsulated, which consumes a large amount of platform computing power resources. And considering that the 5G base station and the UPF are independent network elements, they will be deployed on different payloads, resulting in a significant increase in the routing and switching backplane bandwidth for a large number of data packet forwards on the data plane. In terms of data acceleration, the 5G base station and the UPF need to install and run two sets of data plane acceleration kits, which also incur a large overhead on the satellite platform's memory and power consumption. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for deep integration of the user plane of an on-satellite UPF and a 5G base station to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a method and system for deep integration of the user plane of an on-satellite UPF and a 5G base station, including:

[0008] Deeply integrate the 5G base station module with the core network user plane network element UPF and receive data packets, where both the 5G base station module and the UPF are deployed on the satellite;

[0009] When the data packet is an on-satellite local service, the deeply integrated 5G base station module and the UPF forward the data packet through the inter-satellite link;

[0010] When the data packet is a non-on-satellite local service, the deeply integrated 5G base station module and the UPF forward the data packet to the ground UPF through the feeder link.

[0011] Optionally, during the process of deeply integrating the 5G base station module and the UPF, it includes:

[0012] The 5G base station module and the UPF perform protocol stack integration.

[0013] Optionally, during the process of the 5G base station and the UPF performing protocol stack integration, it includes:

[0014] The 5G base station includes a 5G base station user plane protocol stack and a 5G base station control plane protocol stack;

[0015] Fuse the user plane protocol stack of the 5G base station and the UPF.

[0016] Optionally, the deployment method of the fused 5G base station module and the UPF on the satellite includes: integrated deployment on the same board or independent board deployment;

[0017] The 5G base station module and the UPF are deployed using container virtualization.

[0018] Optionally, during the process of fusing the user plane protocol stack of the 5G base station module and the UPF, it includes:

[0019] The user plane protocol stack of the 5G base station module includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, GTP-U layer, UDP layer, IP layer, L2 layer, and L1 layer;

[0020] The UPF user plane protocol stack of the UPF includes: GTP-U layer, UDP layer, IP layer, L2 layer, and L1 layer;

[0021] The fused user plane protocol stack includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, IP layer, L2 layer, and L1 layer.

[0022] Optionally, when the data packet is an on-satellite local service, during the process of forwarding the data packet through the inter-satellite link by the deeply fused 5G base station module and the UPF, it includes:

[0023] Based on the data packet detection rules configured by the SMF, the deeply fused 5G base station module and the UPF detect the received data packet;

[0024] Detect the user data packet in the data packet and classify the data packet based on the detection result, and send the data packet to the inter-satellite link through the interface for forwarding, where the interface is the N6 interface.

[0025] Optionally, when the data packet is a non-on-satellite local service, during the process of forwarding the data packet to the ground UPF through the feeder link by the deeply fused 5G base station module and the UPF, it includes:

[0026] Based on the data packet detection rules configured by the SMF, the deeply fused 5G base station module and the UPF transmit the data packet through the N9 interface to the feeder link, and then forward it to the ground UPF through the feeder link.

[0027] A system for deep integration of the on-satellite UPF and the user plane of the 5G base station includes:

[0028] A deep fusion module for deeply fusing the 5G base station module on the satellite and the user plane network element UPF, and receiving data packets;

[0029] An on-satellite transmission module for forwarding the data packets through an inter-satellite link when the data packets are on-satellite local services for the 5G base station module and the UPF after deep fusion;

[0030] An on-satellite and ground transmission module for forwarding the data packets to the ground UPF through a feeder link when the data packets are non-on-satellite local services for the 5G base station module and the UPF after deep fusion.

[0031] Optionally, the 5G base station module includes a 5G base station board card module and a 5G base station protocol stack module, where,

[0032] The 5G base station board card module includes a common platform software and a bottom-layer dependency library;

[0033] The 5G base station protocol stack module includes a 5G base station user plane protocol stack and a 5G base station control plane protocol stack.

[0034] Optionally, the deployment method of the 5G base station module and the UPF on the satellite after being fused by the deep fusion module includes: integrated deployment on the same board card or independent board card deployment.

[0035] Optionally, the deep fusion module includes a board card deployment fusion module and a protocol stack fusion module, where,

[0036] The board card deployment fusion module is used for performing board card deployment fusion on the distributed unit DU and the UPF that has undergone container virtualization deployment;

[0037] The protocol stack fusion module is used for fusing the 5G base station user plane protocol stack and the UPF user plane protocol stack.

[0038] Optionally, the 5G base station user plane protocol stack includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, GTP-U layer, UDP layer, IP layer, L2 layer and L1 layer;

[0039] The UPF user plane protocol stack of the UPF includes: GTP-U layer, UDP layer, IP layer, L2 layer and L1 layer;

[0040] The fused user plane protocol stack includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, IP layer, L2 layer and L1 layer.

[0041] Optionally, the on-satellite transmission module includes an N6 interface and a configuration information module, where,

[0042] The N6 interface is used to send data packets to the inter-satellite link;

[0043] The configuration information module is used to detect and classify data packets.

[0044] Optionally, the space-ground transmission module includes an N9 interface and the configuration information module, where

[0045] The N9 interface is used to transmit data packets to the feeder link;

[0046] The configuration information module is used to detect and classify data packets.

[0047] The present invention discloses the following technical effects:

[0048] By deeply integrating the base station with the UPF, canceling the N3 interface between the base station and the UPF, the GTP-U packet encapsulation and decapsulation operations for the user's uplink and downlink data packets are not required frequently, effectively reducing the computing power overhead of the satellite platform, reducing the packet processing delay, and effectively reducing the routing and switching backplane bandwidth of the satellite platform; for the same board deployment method, the data plane acceleration suite can be reused, reducing the memory and power consumption overhead of the satellite platform; by deeply integrating the base station with the UPF, the satellite user data packet shunting is realized, the user data stream is offloaded locally, reducing the transmission delay, alleviating the transmission pressure of the space-ground feeder link, and improving the network data processing efficiency; by deeply integrating the base station with the UPF and modifying based on the 3GPP protocol, except for canceling the N3 interface, the functions of the base station and the UPF are not changed, and other interface protocols are not changed. Description of the Drawings

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0050] Figure 1 It is a schematic diagram of the main functions of the base station in the embodiments of the present invention;

[0051] Figure 2 It is a schematic diagram of the main functions of the core network UPF in the embodiments of the present invention;

[0052] Figure 3 It is a schematic diagram of the base station processing data packet flow in the embodiments of the present invention;

[0053] Figure 4 It is a schematic diagram of the UPF on-satellite network architecture in the embodiments of the present invention;

[0054] Figure 5 Schematic diagram of satellite independent board deployment in an embodiment of the present invention;

[0055] Figure 6 Schematic diagram of container virtualization deployment with UPF and base station baseband on the same board in an embodiment of the present invention;

[0056] Figure 7 Schematic diagram of deep integration deployment of base station and UPF in an embodiment of the present invention;

[0057] Figure 8 Schematic diagram of the user plane protocol stack before deep integration of base station and UPF in an embodiment of the present invention;

[0058] Figure 9 Schematic diagram of the user plane protocol stack after deep integration of base station and UPF in an embodiment of the present invention;

[0059] Figure 10 Schematic diagram of the N9 interface protocol after deep integration of base station and UPF in an embodiment of the present invention;

[0060] Figure 11 Schematic diagram of the data packet processing process before deep integration of base station and UPF in an embodiment of the present invention;

[0061] Figure 12 Schematic diagram of the data packet processing process before deep integration of base station and UPF in an embodiment of the present invention. Detailed implementation manners

[0062] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0063] As Figure 1 shown, the main functions of the 5G base station are as follows:

[0064] Inter-cell radio resource management, bearer control, connected-state mobility control, radio access control, measurement configuration and preparation, dynamic resource allocation (scheduling);

[0065] As Figure 2 shown, the user plane function (UPF) is the core network function responsible for all user plane processing, and its main functions are as follows:

[0066] Data packet routing and forwarding, mobility anchor point, QoS flow mapping, data transmission service.

[0067] In addition, it also includes data packet marking, data packet buffering, traffic usage reports, etc. It may also be the anchor point of a PDU session, supporting branch points to support multi-homed PDU sessions.

[0068] The schematic diagram of the process for the base station to process data packets is as Figure 3 shown.

[0069] The network architecture of the present invention:

[0070] With the improvement of future satellite platform capabilities, future satellite-terrestrial integration will mainly be based on the network architecture of 5G Non-terrestrial Network (NTN). After the UPF network element of the core network is deployed on the satellite, its network architecture will be as Figure 4 shown. Among them, the satellite terminal is connected to the satellite access network through the user link. The satellite access network adopts a CU and DU separation architecture, including a Centralized Unit (CU) and a Distributed Unit (DU). Information transmission and exchange are carried out between different satellites through inter-satellite links. The satellite transmits satellite information to the gateway station through the feeder link, and the gateway station defines a dedicated interface to connect to the terrestrial core network to achieve interconnection with the terrestrial network.

[0071] Design of the deployment method of satellite platform boards:

[0072] After the UPF is deployed on the satellite, there are two possible deployment scenarios as follows:

[0073] a) Stand-alone board deployment

[0074] The UPF is deployed in the form of a stand-alone board, centrally responsible for the data processing and forwarding functions of multiple channels. The stand-alone board deployment scenario is as Figure 5 shown.

[0075] b) Co-board container virtualization deployment of UPF and base station baseband

[0076] The UPF adopts the container virtualization deployment method and can be deployed in a co-board fusion manner with the base station baseband. The co-board deployment scenario diagram is as Figure 6 shown.

[0077] When the user plane of the base station is deeply integrated with the UPF, the reference for its deployment method is as Figure 7 shown. At this time, both the UPF and the base station are deployed on the same board. For the access network CU and DU separation architecture, it is considered to deploy the UPF and DU on the same board.

[0078] The protocol stack architecture of the 5G base station is:

[0079] The 5G network architecture protocol stack is divided into two planes: the user plane and the control plane. The user plane (UP) protocol stack is the protocol cluster used for user data transmission, and the control plane (CP) protocol stack is the protocol cluster used for the transmission of system control signaling.

[0080] The deep integration of the base station and UPF proposed in the present invention mainly focuses on the user plane. Among them:

[0081] User plane protocol stack before the deep integration of the base station and UPF:

[0082] As Figure 8 shown, the user plane protocol stack of the core network UPF network element from top to bottom is: GTP-U layer, UDP layer, IP layer, L2 layer, and L1 layer. The user plane protocol of the 5G base station from top to bottom is: SDAP layer, PDCP layer, RLC layer, MAC layer, and PHY layer. In order to forward user plane data with the UPF through the N3 interface, the UPF protocol stack is also required at the same time.

[0083] User plane protocol stack after the deep integration of the base station and UPF:

[0084] As Figure 9 shown, after the deep integration of the 5G base station and UPF, from the perspective of the user plane protocol stack, it only needs to be aligned with the terminal protocol stack, and there is no need to perform GTP-U packet encapsulation and decapsulation operations on the data packet when transmitting data between the base station and the UPF. Instead, after the SDAP processes the data packet received from the terminal, it is directly handed over to the UPF for processing.

[0085] Regarding the N3 interface in the prior art:

[0086] The method for deep integration of the 5G base station and UPF proposed in the present invention shows that when transmitting uplink and downlink data packets between the base station and the UPF, there is no need to perform GTP-U packet encapsulation and decapsulation operations on the data packets. That is, the N3 interface between the base station and the UPF can be directly cancelled. Figure 8 and Figure 9

[0087] The N6 interface used for on-orbit transmission:

[0088] From Figure 8 and Figure 9 it can be seen that after the deep integration of the 5G base station and UPF, for the N6 interface, the processing process of uplink and downlink data packets is not affected. The UPF can detect the incoming user data traffic and classify the traffic according to the data packet detection rules configured by the SMF for the data packets received by the SDAP, and then forward them to the routing exchange.

[0089] The N9 interface used for space-ground transmission: ​

[0090] The N9 interface is the interface between UPFs. From Figure 10 It can be seen that for UPFs between satellite constellations, it can be equivalent to directly forwarding data packets through the N6 interface. For terrestrial UPFs, data packets need to be forwarded through the N9 interface. Comparing before and after the integration of the base station and the core network, there is no modification to the 5G core network protocol stack.

[0091] The data packet processing flow in this embodiment includes:

[0092] Data packet forwarding flow before deep integration of the base station and UPF:

[0093] As Figure 11 shown, the data packet processing flow before deep integration of the base station and UPF is as follows: Data packets from the terminal are processed by PHY / MAC / RLC / PDCP / SDAP and then forwarded to the UPF through the N3 interface. The UPF distributes the data packets to the local network through inter-satellite routing (N6 interface) according to the configuration information, or forwards them to the terrestrial UPF through the N9 interface.

[0094] Data packet forwarding flow after deep integration of the base station and UPF:

[0095] As Figure 12 shown, using the method of deep integration of the base station and UPF proposed in the present invention, the data packet processing flow is as follows: Data packets from the terminal are processed by PHY / MAC / RLC / PDCP / SDAP and then directly handed over to the UPF for processing. The UPF distributes the data packets to the local network through inter-satellite routing (N6 interface) according to the configuration information, or forwards them to the terrestrial UPF through the N9 interface.

[0096] In terms of the user plane, the present invention deeply integrates the on-satellite base station and UPF, and cancels the N3 interface between the base station and UPF. The base station can directly hand over the data packets of the SDAP protocol entity to the UPF for processing without performing GTP-U packet encapsulation and decapsulation operations, effectively reducing the computing power overhead;

[0097] Removing the N3 interface message forwarding between the base station and UPF avoids multiple memory copies, reduces the packet processing delay, and reduces the satellite platform routing and switching backplane bandwidth.

[0098] When forwarding data, the data plane acceleration suite can be reused (shared), and there is no need to deploy two sets of services for the base station payload and UPF payload respectively on the satellite platform, reducing the memory and power consumption overhead of the satellite platform.

[0099] Logically equivalent to the base station separation solution. That is, based on the traffic splitting technology, the satellite user data stream is locally offloaded, reducing the transmission delay and alleviating the transmission pressure of the space-ground feeder link, thereby improving the network data processing efficiency.

[0100] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A method for deep integration of the on - satellite UPF and the user plane of the 5G base station, characterized in that, it includes the following steps: Deeply integrate the 5G base station module with the user plane network element UPF of the core network and receive data packets, where both the 5G base station module and the UPF are deployed on the satellite; When the data packet is an on - satellite local service, the deeply integrated 5G base station module and UPF forward the data packet through the inter - satellite link; When the data packet is a non - on - satellite local service, the deeply integrated 5G base station module and UPF forward the data packet to the ground UPF through the feeder link; During the process of deeply integrating the 5G base station module and the UPF, it includes: The 5G base station module and the UPF perform protocol stack integration; During the process of the 5G base station and the UPF performing protocol stack integration, it includes: The 5G base station includes a 5G base station user plane protocol stack and a 5G base station control plane protocol stack; Integrate the 5G base station user plane protocol stack and the UPF; The deployment method of the deeply integrated 5G base station module and UPF on the satellite includes: integrated deployment on the same board or independent board deployment; The 5G base station module and the UPF are deployed using container virtualization; During the process of integrating the 5G base station module user plane protocol stack and the UPF, it includes: The 5G base station module user plane protocol stack includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, GTP - U layer, UDP layer, IP layer, L2 layer, and L1 layer; The UPF user plane protocol stack of the UPF includes: GTP - U layer, UDP layer, IP layer, L2 layer, and L1 layer; The integrated user plane protocol stack includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, IP layer, L2 layer, and L1 layer.

2. The method according to claim 1, characterized in that, When the data packet is an on - satellite local service, during the process of the deeply integrated 5G base station module and UPF forwarding the data packet through the inter - satellite link, it includes: Based on the data packet detection rules configured by the SMF, the deeply integrated 5G base station module and UPF detect the received data packet; Detect the user data packet in the data packet and classify the data packet based on the detection result, and send the data packet to the inter - satellite link for forwarding through the interface, where the interface is the N6 interface.

3. The method according to claim 1, characterized in that, When the data packet is a non - on - satellite local service, during the process of the deeply integrated 5G base station module and UPF forwarding the data packet to the ground UPF through the feeder link, it includes: Based on the data packet detection rules configured by the SMF, the deeply integrated 5G base station module and UPF transmit the data packet to the feeder link through the N9 interface, and then forward it to the ground UPF through the feeder link.

4. A system for deep integration of the on - satellite UPF and the user plane of the 5G base station, characterized in that, it includes: The deep fusion module is used to deeply fuse the 5G base station module on the satellite and the user plane network element UPF, and receive data packets; The on-satellite transmission module is used to forward the data packets through the inter-satellite link when the data packets are on-satellite local services between the 5G base station module after deep fusion and the UPF; The satellite-ground transmission module is used to forward the data packets to the ground UPF through the feeder link when the data packets are non-on-satellite local services between the 5G base station module after deep fusion and the UPF; The 5G base station module includes a 5G base station board module and a 5G base station protocol stack module, where, The 5G base station board module includes a common platform software and a bottom-layer dependency library; The 5G base station protocol stack module includes a 5G base station user plane protocol stack and a 5G base station control plane protocol stack; The deployment method of the 5G base station module and the UPF on the satellite after being fused by the deep fusion module includes: integrated deployment on the same board or independent board deployment; The deep fusion module includes a board deployment fusion module and a protocol stack fusion module, where, The board deployment fusion module is used to perform board deployment fusion on the distributed unit DU and the UPF that has undergone container virtualization deployment; The protocol stack fusion module is used to fuse the 5G base station user plane protocol stack and the UPF user plane protocol stack; The 5G base station user plane protocol stack includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, GTP-U layer, UDP layer, IP layer, L2 layer, and L1 layer; The UPF user plane protocol stack of the UPF includes: GTP-U layer, UDP layer, IP layer, L2 layer, and L1 layer; The fused user plane protocol stack includes: SDAP layer, PDCP layer, RLC layer, MAC layer, PHY layer, IP layer, L2 layer, and L1 layer.

5. The system according to claim 4, characterized in that, The on-satellite transmission module includes an N6 interface and a configuration information module, where, The N6 interface is used to send data packets to the inter-satellite link; The configuration information module is used to detect and classify data packets.

6. The system according to claim 4, characterized in that, The satellite-ground transmission module includes an N9 interface and a configuration information module, where, The N9 interface is used to transmit data packets to the feeder link; The configuration information module is used to detect and classify data packets.

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