CN115915482A

CN115915482A - Session establishment method and device

Info

Publication number: CN115915482A
Application number: CN202111204709.XA
Authority: CN
Inventors: 李丽丝; 许丽香; 麻晓宁
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2021-08-03
Filing date: 2021-10-15
Publication date: 2023-04-04

Abstract

The invention relates to a session establishment method and equipment. According to an aspect of the present invention, a method performed by a second node in a wireless communication system is disclosed, the method comprising: receiving a message for bearer establishment request from a first node; and sending a message for bearing establishment feedback to the first node.

Description

Session establishment method and device

Technical Field

The present application relates to the field of wireless communication technologies, and in particular, to a session establishment method and device.

Background

In order to meet the increasing demand for wireless data communication services since the deployment of 4G communication systems, efforts have been made to develop improved 5G or quasi-5G communication systems. Therefore, the 5G or quasi-5G communication system is also referred to as a "super 4G network" or a "post-LTE system".

Wireless communication is one of the most successful innovations in modern history. Recently, the number of subscribers of wireless communication services exceeds 50 billion, and is still rapidly increasing. Due to the increasing popularity of smart phones and other mobile data devices (e.g., tablet computers, notebook computers, netbooks, e-book readers, and machine type devices) among consumers and businesses, the demand for wireless data services is growing rapidly. To meet the high growth of mobile data services and support new applications and deployments, it is important to improve radio interface efficiency and coverage.

Disclosure of Invention

According to an aspect of the present application, there is provided a method performed by a second node in a wireless communication system, the method comprising: receiving a message for bearer establishment request from a first node; and sending a message for bearing establishment feedback to the first node.

Optionally, if the second node determines that the requested bearer establishment fails, the message for bearer establishment feedback includes information indicating a backoff time.

Optionally, if the second node determines that the requested bearer can not be established temporarily, the message for bearer establishment feedback includes information indicating that suspension is requested.

Optionally, the information for indicating that the request is pending further comprises at least one of a pending indication and a pending time.

Optionally, if the requested bearer is for supporting Session and Service Continuity (SSC), the message for bearer setup request includes information related to the old PDU Session.

Optionally, the information related to the old PDU session comprises at least one of:

information indicating an SSC pattern;

information indicating an old PDU session ID and/or an old QoS flow identification; and

time information indicating the remaining lifetime of the old PDU session.

According to another aspect of the present application, there is provided a method performed by a first node in a wireless communication system, the method comprising: sending a message for bearing a building request to a second node; a message for bearer establishment feedback is received from the second node.

Optionally, if the second node determines that the requested bearer establishment fails, the message for bearer establishment feedback includes information indicating a back-off time;

optionally, if the second node determines that the requested bearer can not be established temporarily, the message for bearer establishment feedback comprises information indicating that the request is pending.

Optionally, the information for indicating that the request is suspended further includes at least one of a suspension indication and a suspension time.

According to another aspect of the present application, there is provided a method performed by a second node in a wireless communication system, the method comprising: receiving a message from a first node indicating that there are multiple bearer establishment requests to send simultaneously; based on the message, resources for establishing a plurality of bearers are prepared.

Optionally, the message for indicating that there are multiple bearer establishment requests to be sent simultaneously includes at least one of the following information: requested bearer quality of service, qoS, requirements; the number of requested bearers; requested bearer availability time; requested capacity requirements.

Optionally, the method further comprises: sending a feedback message to the first node; the feedback message comprises information indicating a resource preparation result and/or information related to a transmission policy of a plurality of bearer establishment requests.

Optionally, the information indicating the resource preparation result and/or the related information of the sending policy of the multiple bearer establishment requests includes at least one of the following information: a resource preparation success indication; a resource preparation failure indication; the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time.

According to another aspect of the present application, there is provided a method performed by a first node in a wireless communication system, the method comprising: sending a message to a second node for indicating that a plurality of bearer establishment requests are sent at the same time; and simultaneously sending a plurality of request messages for bearer establishment to the second node.

Optionally, the method further comprises: receiving a feedback message from a first node; the feedback message comprises information indicating resource preparation results and/or information related to a transmission policy for multiple bearer establishment requests.

Optionally, the information indicating a resource preparation result and/or related information of a sending policy for multiple bearer establishment requests includes at least one of the following information: a resource preparation success indication; a resource preparation failure indication; the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time.

According to another aspect of the present application, there is provided a method performed by a first node in a wireless communication system, the method comprising: -receiving from the second node related information indicating preemption restrictions, -the first node sending a message for a bearer establishment request considering said related information indicating preemption restrictions.

Optionally, the related information for indicating preemption limitation includes related information for indicating a number of bearer preemption processes that can be supported on the second node.

Optionally, sending the message for the bearer establishment request based on the relevant information indicating the preemption limitation further includes: the first node considers the relevant information for indicating the preemption limitation and decides the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time; and sending the message for the bearer establishment request based on the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time.

According to another aspect of the present application, there is provided a method performed by a second node in a wireless communication system, the method comprising: sending relevant information for indicating preemption restrictions to the first node, and receiving a message for bearer establishment request from the first node.

Optionally, the related information for indicating the preemption restriction includes related information for indicating a number of bearer preemption processes that can be supported at the second node.

Optionally, the first node considers the relevant information for indicating preemption limitation, and sending the message for bearer establishment request further includes: the first node considers the relevant information for indicating the preemption restriction and decides the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time; and sending the message for the bearer establishment request based on the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time.

According to yet another aspect of the present application, there is provided a first node in a wireless communication system, comprising: a transceiver to transmit/receive signals to/from other network entities; and a controller controlling overall operation of the first node, wherein the first node is configured to perform the method described above as being performed by the first node.

According to yet another aspect of the application, there is provided a second node in a wireless communication system, comprising: a transceiver to transmit/receive signals to/from other network entities; and a controller controlling overall operation of the second node, wherein the second node is configured to perform the method described above as being performed by the second node.

Drawings

The foregoing and additional aspects and advantages of the present application will become more apparent and readily appreciated from the following description, taken in conjunction with the accompanying drawings, wherein:

fig. 1 is an exemplary system architecture for System Architecture Evolution (SAE).

Fig. 2 is an exemplary system architecture according to various embodiments of the invention.

Fig. 3A illustrates a method of session establishment and control according to an exemplary embodiment of the invention.

Fig. 3B illustrates a method of session establishment and control according to another exemplary embodiment of the present invention.

Fig. 4A illustrates a method of session establishment and control according to another exemplary embodiment of the present invention.

Fig. 4B illustrates a method of session establishment and control according to another exemplary embodiment of the present invention.

Fig. 4C illustrates a method of session establishment and control according to another exemplary embodiment of the present invention.

Fig. 5 shows a method of session establishment and control according to a further exemplary embodiment of the present invention.

Fig. 6 illustrates a method of session establishment and control according to still another exemplary embodiment of the present invention.

Fig. 7 shows a block diagram of a first node according to an exemplary embodiment of the invention.

Fig. 8 shows a block diagram of a second node according to an exemplary embodiment of the invention.

Detailed Description

Figures 1 through 8, discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the invention may be implemented in any suitably arranged system or device.

Fig. 1 is an exemplary system architecture 100 for System Architecture Evolution (SAE). A User Equipment (UE) 101 is a terminal device for receiving data. An evolved universal terrestrial radio access network (E-UTRAN) 102 is a radio access network that includes macro base stations (eNodeB/NodeB) that provide access to a radio network interface for UEs. Mobility Management Entity (MME) 103 is responsible for managing mobility context, session context, and security information for the UE. Serving Gateway (SGW) 104 mainly provides the functions of the user plane, and MME 103 and SGW 104 may be in the same physical entity. A packet data network gateway (PGW) 105 is responsible for charging, lawful interception, etc., and may also be in the same physical entity as the SGW 104. A Policy and Charging Rules Function (PCRF) 106 provides quality of service (QoS) policy and charging criteria. The general packet radio service support node (SGSN) 108 is a network node device in the Universal Mobile Telecommunications System (UMTS) that provides routing for the transmission of data. The Home Subscriber Server (HSS) 109 is the home subsystem of the UE and is responsible for protecting user information including the current location of the user equipment, the address of the serving node, user security information, the packet data context of the user equipment, etc.

Fig. 2 is an exemplary system architecture 200 in accordance with various embodiments of the invention. Other embodiments of the system architecture 200 can be used without departing from the scope of the present invention.

A User Equipment (UE) 201 is a terminal device for receiving data. The next generation radio access network (NG-RAN) 202 is a radio access network comprising base stations (gbb or eNB connected to the 5G core network 5GC, also called NG-gbb) providing access to radio network interfaces for UEs. An access control and mobility management function (AMF) 203 is responsible for managing the mobility context of the UE, and security information. A user plane function entity (UPF) 204 mainly provides functions of the user plane. The session management function entity SMF205 is responsible for session management. The Data Network (DN) 206 contains services such as the operator, access to the internet, and services for third parties.

With the development of wireless technology, in the 5G architecture, the functional modules originally located on the same base station are separated. Some functional modules are closer and closer to users, and other modules are pool-assembled and virtualized for centralized deployment. That is, the base station may be divided into two parts, one of which is a Central Unit (CU) and the other of which is a Distribution Unit (DU). The DU is closer to the user, and the CU is far away from the antenna, so that multi-antenna connection can be supported, and the network performance is improved. One CU may connect multiple DUs and the functions on the CU may be virtualized. CU and DU are connected via an F1 interface, which is also called fronthaul interface or fronthaul connection. The functions of RRC (Radio Resource Control), PDCP (Packet Data Convergence Protocol) are implemented on the CU, and the functions of RLC (Radio Link Control), MAC (Media Access Control), and physical layer are implemented on the DU.

Mission Critical (MC) communication platform and MC services have been a key priority item of 3GPP in recent years and are expected to develop in the future by receiving more demands from different departments of the global Critical communication industry. Mission-critical related functions have been staged as driven by 3GPP release plans, each release comprising a complete set of standards for equipment suppliers and operators to implement and deploy in stages according to market demand.

The MC service relies on successfully establishing a dedicated bearer with QoS required by media, when an operator actually deploys a mission-critical system, it is found that a problem may occur when establishing a dedicated bearer for a group call on a base station with a high load, when the resource of the base station is insufficient, a bearer corresponding to the MC service may preempt the resource of other bearers, but because the base station has a bearer preemption rate limit (for example, within a certain time, the bearer preemption cannot exceed a certain number, for example, 30 per minute), a request exceeding the limit fails, but for the MC server, it is unknown that the reason for the failure is that the MC server and a core network initiated by the bearer establishment request do not have a good mechanism to avoid the failure due to the preemption limit of the base station, or in this case, the success rate of bearer establishment is increased to ensure the successful establishment of the MC service.

The embodiment of the invention provides a plurality of methods, and the establishment of the MC service under the limitation of the base station is optimized to improve the success rate of the establishment and ensure that the service is smoothly carried out.

Exemplary embodiments of the present invention are further described below with reference to the accompanying drawings.

The text and drawings are provided as examples only to assist in understanding the invention. They should not be construed as limiting the scope of the invention in any way. While certain embodiments and examples have been provided, it will be apparent to those skilled in the art, based on the disclosure herein, that changes can be made in the embodiments and examples shown without departing from the scope of the invention.

Fig. 3 illustrates a method of session establishment according to an exemplary embodiment of the present invention. It should be understood that fig. 3 omits a detailed description of steps not relevant to the present invention. The method of fig. 3 comprises the steps of:

step 301, the first node sends a message for bearer establishment request to the second node. According to one embodiment, the requested bearer is used for MC traffic, e.g., the bearer may be a dedicated bearer used in MC group calls (group calls). The first node is a core network node, or a CU (Central Unit) or a CU-CP (Central Unit-Control Plane) in a base station, the core network node may be an Access and Mobility Management Function (AMF) or a Session Management Function (SMF) or a Mobility Management Entity (MME), and the second node may be a DU (Distributed Unit) or a CU-UP (Central Unit-User Plane) in a base station, or a Central Unit-User Plane. According to one embodiment, in the case that the first node is a core network node and the second node is a base station, the message for carrying the establishment request may be a PDU (Packet Data Unit or Protocol Data Unit) session resource establishment request message or a PDU session resource modification request message. According to another embodiment, the message for bearer establishment request may be a UE context establishment request message or a UE context modification request message in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station. According to another embodiment, the message for the bearer establishment request may be a bearer context establishment request or a bearer context modification request in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station. It should be appreciated that the above embodiments are merely examples, and the first node, the second node, and the message for the bearer establishment request are not limited thereto.

And the second node receives the message for the bearer establishment request.

Step 302, the second node sends a message for bearer establishment feedback to the first node.

If the second node determines that the bearer establishment requested in step 301 fails, for example, the requested bearer is used for MC service and the base station has preemption restrictions, the message for bearer establishment feedback includes information indicating a backoff time (backoff time) to notify the first node of the time for reattempting to initiate the bearer establishment request, so as to improve the success rate of the next bearer establishment request. And the first node receives the message for the bearer establishment feedback and the information contained in the message, and resends the message for the bearer establishment request to the second node by considering the information for indicating the back-off time. According to one embodiment, in case the first node is a core network node and the second node is a base station, the message for bearer establishment feedback may be a PDU session resource establishment feedback message or a PDU session resource modification feedback message. According to another embodiment, in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station, the message for bearer establishment feedback may be a UE context establishment failure message or a UE context establishment feedback message or a UE context modification failure message. According to another embodiment, in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station, the message for bearer establishment feedback may be a bearer establishment failure message or a bearer establishment feedback message or a bearer modification failure message or a bearer modification feedback message. It should be understood that the above embodiments are merely examples, and the first node, the second node, and the message for bearer establishment feedback are not limited thereto.

If the second node determines that the bearer requested in step 301 is temporarily not able to be established, but considering that the request for the bearer is MC traffic, the second node may establish the requested bearer in the near future, and the message for bearer establishment feedback includes information indicating that the request is suspended to inform the first node that the request in step 301 is temporarily suspended, and the second node may process the request later. And after receiving the message for bearing the bearer establishment feedback and the information contained in the message, the first node continues to wait for the feedback of the second node. According to one embodiment, in case the first node is a core network node and the second node is a base station, the message for bearer establishment feedback may be a PDU session resource establishment feedback message or a PDU session resource modification feedback message. According to another embodiment, in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station, the message for bearer establishment feedback may be a UE context establishment failure message or a UE context establishment feedback message or a UE context modification failure message. According to another embodiment, the message for bearer establishment feedback may be a bearer establishment failure message or a bearer establishment feedback message or a bearer modification failure message or a bearer modification feedback message in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station. The message for bearer establishment feedback may also be a message sent by the other second node to the first node to indicate that the request is pending. It should be understood that the above embodiments are merely examples, and the first node, the second node, and the message for bearer establishment feedback are not limited thereto.

In the present invention, the establishment of the Bearer can be realized by the establishment of a UE context, or the establishment of a PDU session or the establishment of an E-RAB (Evolved Universal Terrestrial Radio Access Network-Radio Access Bearer), and the establishment of the Bearer can also refer to the establishment of a PDU session, the establishment of a QoS stream, the establishment of a DRB, the establishment of an E-RAB or the establishment of a logical channel, which refers to the establishment of a logical data transmission channel capable of providing different services with specific QoS. In the present invention, a bearer may also refer to a PDU session, a QoS flow, a DRB, or a logical channel.

According to the method provided by the exemplary embodiment of the application, the establishment success rate of the MC service can be improved and the key task can be ensured to be smoothly and immediately carried out under the condition that a plurality of bearing establishment requests related to the key task service exist simultaneously and the base station has high load and/or the base station has preemption limitation.

Fig. 3B illustrates a method of session establishment according to another exemplary embodiment of the present invention. It should be understood that fig. 3B omits detailed descriptions of steps not relevant to the present invention. The method of FIG. 3B includes the steps of:

in step 311, the first node sends a message for bearer establishment request to the second node. According to one embodiment, the requested bearer is used for MC traffic, e.g., the bearer may be a dedicated bearer used in MC group calls (group calls). According to another embodiment, the requested bearer is used to support Session and Service Continuity (SSC), such as SSC mode 3, i.e., a new PDU Session, i.e., the requested PDU Session, in which the requested bearer is located, will replace an old PDU Session. The first node is a core network node, or a CU or CU-CP in a base station, the core network node may be an AMF or an SMF or an MME, and the second node may be a base station, or a DU or CU-UP in a base station. According to one embodiment, in case the first node is a core network node and the second node is a base station, the message for bearer establishment request may be a PDU session resource establishment request message or a PDU session resource modification request message. According to another embodiment, the message for bearer establishment request may be a UE context establishment request message or a UE context modification request message in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station. According to another embodiment, the message for the bearer establishment request may be a bearer context establishment request or a bearer context modification request in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station. According to another embodiment, in case the first node is a source base station in a handover procedure and the second node is a target base station in a handover procedure, the message for bearer establishment request may be a handover request message. According to another embodiment, in case that the first node is a base station that last serves the UE when the UE enters an INACTIVE (INACTIVE) state, and the second node is a base station that the UE newly accesses from the INACTIVE state to an ACTIVE (ACTIVE) state, the message for the bearer establishment request may be an acquire UE context feedback message. It should be appreciated that the above embodiments are merely examples and that the first node, the second node, and the message for the bearer establishment request are not limited thereto.

The message may include information related to the old PDU session if the requested bearer is for supporting the SSC. For example, the information related to the old PDU session may be information related to the old PDU session in the SSC pattern 3. In the present invention, the old PDU session related information may also be referred to as old bearer related information, which are the same in meaning. In the present invention, the requested bearer may also be referred to as a requested PDU session, which are synonymous.

And the second node receives the message for the bearer establishment request. The second node takes into account the information related to the old PDU session when performing admission control (admission control) and/or rate control on the PDU session and/or QoS flow requested to be established. In one embodiment, the admission control performed by the second node is network-Slice admission control, i.e. the second node ensures that the sum of GFBR (Guaranteed Flow Bit Rate, GFBR) values of allowed GBR QoS flows does not exceed the UE-Slice Maximum Bit Rate, UE-Slice-MBR (MBR). In one embodiment, the rate control performed by the second node is network slice rate control, i.e. the second node reserves and/or allocates network slice resources for establishing a successful GBR QoS flow. It should be appreciated that the above embodiments are merely examples and the types of admission control and/or rate control are not limited thereto.

And if the message for bearing the establishment request comprises the information related to the old PDU conversation, the second node takes the information into consideration for admission control. According to one embodiment, if the message for bearer establishment request includes information related to the old PDU session, when the second node performs admission control, the second node performs admission control on a Guaranteed Bit Rate (GBR) QoS flow in the requested PDU session in consideration of the information related to the old PDU session, for example, the second node performs admission control by jointly considering a GBR QoS flow in the new PDU session and a GBR QoS flow in the old PDU session corresponding thereto, that is, the second node may halve a GFBR value of the GBR QoS flow in the new PDU session. According to another embodiment, if the message for bearer establishment request includes information related to the old PDU session, the second node directly grants the new PDU session request without admission control to the GBR QoS flow in the new PDU session, taking into account that the GBR QoS flow in the channel PDU session is to replace the QoS flow in the old PDU session. It should be understood that the above embodiments are only examples, and the specific implementation method for performing admission control in consideration of information related to old PDU sessions is not limited thereto.

And if the message for bearing the establishment request comprises the information related to the old PDU session, the second node performs rate control on the new PDU session by considering the information. According to one embodiment, the second node may reserve and/or allocate resources for the GBR QoS flows in the new PDU session and the GBR QoS flows in the old PDU session corresponding thereto in a certain proportion, for example 50% each, i.e. resources corresponding to 50% GFBR are reserved for each QoS flow, and ensure that the sum of their reserved resources is greater than or equal to GFBR, which is the GFBR requested by one of the QoS flows. It should be understood that the above embodiments are only examples, and the specific implementation method for rate control considering the information related to the old PDU session is not limited thereto.

Step 312, the second node sends a message for bearer establishment feedback to the first node.

If the second node determines that the bearer establishment requested in step 311 fails, for example, the requested bearer is used for MC traffic and the base station has preemption restrictions or the requested bearer fails to be admitted due to network slice admission control, the message for bearer establishment feedback includes information indicating a backoff time (backoff time) to notify the first node of the time for reattempting to initiate the bearer establishment request, so as to improve the success rate of the next bearer establishment request. The backoff time may be a value predicted or calculated by the second node. And the first node receives the message for the bearer establishment feedback and the information contained in the message, and resends the message for the bearer establishment request to the second node by considering the information for indicating the back-off time. According to one embodiment, in case the first node is a core network node and the second node is a base station, the message for bearer establishment feedback may be a PDU session resource establishment feedback message or a PDU session resource modification feedback message. According to another embodiment, in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station, the message for bearer establishment feedback may be a UE context establishment failure message or a UE context establishment feedback message or a UE context modification failure message. According to another embodiment, in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station, the message for bearer establishment feedback may be a bearer establishment failure message or a bearer establishment feedback message or a bearer modification failure message or a bearer modification feedback message. According to another embodiment, in case the first node is a source base station in a handover procedure and the second node is a target base station in a handover procedure, the message for bearer establishment feedback may be a handover request acknowledgement or a handover failure message. It should be appreciated that the above embodiments are merely examples, and the first node, the second node, and the message for bearer establishment feedback are not limited thereto.

If the second node determines that the bearer requested in step 311 could not be established temporarily, but considering that the request for said bearer is MC traffic or that the PDU session in which the request for said bearer is located is to replace an old PDU session, the second node may establish said requested bearer in the near future, said message for bearer establishment feedback comprising information indicating that the request is pending to inform the first node that the request in step 301 is pending temporarily, which the second node will process later. And after receiving the message for bearing the bearer establishment feedback and the information contained in the message, the first node continues to wait for the feedback of the second node. According to one embodiment, in case the first node is a core network node and the second node is a base station, the message for bearer establishment feedback may be a PDU session resource establishment feedback message or a PDU session resource modification feedback message. According to another embodiment, in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station, the message for bearer establishment feedback may be a UE context establishment failure message or a UE context establishment feedback message or a UE context modification failure message. According to another embodiment, in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station, the message for bearer establishment feedback may be a bearer establishment failure message or a bearer establishment feedback message or a bearer modification failure message or a bearer modification feedback message. The message for bearer establishment feedback may also be a message sent by the other second node to the first node to indicate that the request is pending. It should be appreciated that the above embodiments are merely examples, and the first node, the second node, and the message for bearer establishment feedback are not limited thereto.

In the present invention, the establishment of the Bearer can be realized by UE context establishment, PDU session establishment, or E-RAB (Evolved Universal Terrestrial Radio Access Network-Radio Access Bearer), and the establishment of the Bearer can also refer to the establishment of QoS streams, the establishment of DRBs, or the establishment of E-RAB, which refers to the establishment of logical data transmission channels capable of providing different services with specific QoS.

According to the method provided by the exemplary embodiment of the application, the node of the radio access network can also know the relationship between the newly established PDU session and the old PDU session, even when the remaining radio resources or network slice resources are insufficient or limited, the continuity of the session and the service is ensured, the success rate of establishing the session or the bearer is improved, the resources are more effectively used, and the user experience is improved.

Fig. 4A illustrates a method of session establishment and control according to another exemplary embodiment of the present invention. It should be understood that fig. 4A omits a detailed description of steps not relevant to the present invention. The method of FIG. 4A includes the steps of:

step 4a01, a first node sends a first message to a second node, where the first node is a core network node, the core network node may be an AMF or an SMF, and the second node may be a base station. The first message is a message for QoS flow setup, such as for MC traffic, and may be a PDU session resource setup request message or a PDU session resource modification request message sent by AMF/SMF to the gNB, which are only examples and are not limiting.

The second node receives the message.

And 4A02, the second node sends a second message to the first node. The second message may be a PDU session resource establishment feedback message or a PDU session resource modification feedback message or a message for indicating suspension of a PDU session request, where the message may include a PDU session resource establishment feedback transmission IE (Information Element), a PDU session resource establishment unsuccessful transmission IE, and/or a PDU session resource suspension transmission IE.

For each successfully established PDU session resource, if there is a failed QoS flow list, the PDU session resource establishment feedback transmission IE shall include the failed QoS flow list and a cause value of the failed establishment of each failed QoS flow. If the cause value is a cause related to pre-preemption limitation (pre-preemption limit), a Backoff time (Backoff time) for informing the first node of the time when the QoS flow establishment request can be re-initiated is included in the PDU session resource establishment feedback transmission IE to increase the success rate of the re-request.

For each PDU session resource failed to be established, a cause value of the failed establishment should be included in the PDU session resource establishment unsuccessful transmission IE, and if the cause value is a cause related to pre-preemption limitation (pre-preemption), a Backoff time (Backoff time) should be included in the PDU session resource establishment unsuccessful transmission IE, and the Backoff time is used to notify the first node of the time when the PDU session request can be reinitiated, so as to improve the success rate of the re-request.

For each requested PDU session resource or requested QoS flow resource in each requested PDU session resource, if the request is pending, the PDU session resource setup feedback transmission IE or the PDU session resource pending transmission IE will include information indicating that the request is pending, which may be at least one of:

-a Pending indication (Pending indication) indicating to the first node that the request for PDU session resources or QoS flow resources in PDU session resources is Pending, such that the first node is continuing to wait for the result of the request;

-a Pending time (Pending time) indicating the time at which the first node's request for a PDU session resource or a QoS flow resource in a PDU session resource is Pending, so that the first node considers that the request is re-initiated after said time.

According to the method provided by the exemplary embodiment of the application, the establishment success rate of the MC service can be improved and the key task can be ensured to be smoothly and immediately performed under the condition that a plurality of bearer establishment requests related to the key task service exist at the same time and the base station has high load and/or the base station has preemption limitation.

Fig. 4B illustrates a method of session establishment and control according to yet another exemplary embodiment of the present invention. It should be understood that fig. 4B omits detailed descriptions of steps that are not relevant to the present invention. The method of FIG. 4B includes the steps of:

step 4B01, a first node sends a first message to a second node, where the first node is a core network node, the core network node may be an MME, and the second node may be a base station. The first message may be an E-RAB establishment request message or an E-RAB modification request message sent by the MME to the eNB, the E-RAB being for MC traffic.

The second node receives the message.

And 4B02, the second node sends a second message to the first node.

When the first node is an MME and the second node is an eNB, the second message may be an E-RAB establishment feedback message or an E-RAB modification feedback message or a message indicating suspension of the E-RAB request.

The eNB shall report the results of all requested E-RABs to the MME in an E-RAB establishment feedback message or an E-RAB modification feedback message.

If there is an E-RAB that cannot be established, the list of E-RABs that cannot be established must be included in the E-RAB failure establishment list IE. The cause value for failure should also be included in the IE. If the cause value is a cause related to pre-preemption limitation (pre-preemption limit), a Backoff time (Backoff time) should be included in the IE to inform the first node of the time when the E-RAB establishment request can be reinitiated to improve the success rate of the re-request.

If the E-RAB request is temporarily suspended, the E-RAB failure to establish list IE or the E-RAB establishment list IE or the E-RAB request suspension list will include information indicating that the request is suspended, which may be at least one of the following information:

-a pending indication (pending indication) indicating that the first node's E-RAB request is pending, so that the first node is continuing to wait for the result of the request;

-a suspension time (pending time) indicating the time at which the request of the first node E-RAB is suspended, so that the first node considers that the request is re-initiated after said time.

According to the method provided by the exemplary embodiment of the application, under the condition that a plurality of bearing establishment requests related to the key task service exist simultaneously and the base station has high load and/or the base station has preemption limitation, the establishment success rate of the MC service is improved, the key task can be smoothly and timely carried out, and the safety of lives and properties is ensured.

Fig. 4C illustrates a method of session establishment and control according to another exemplary embodiment of the present invention. It should be understood that fig. 4C omits a detailed description of steps not relevant to the present invention. The method of FIG. 4C includes the steps of:

and 4C01, the first node sends the first message to the second node. The first message is for requesting PDU session establishment or modification. The first node is a core network node, or a CU or CU-CP in a base station, the core network node may be an AMF or an SMF or an MME, and the second node may be a base station, or a DU or CU-UP in a base station. According to one embodiment, in case the first node is a core network node and the second node is a base station, the message for bearer establishment request may be a PDU session resource establishment request message or a PDU session resource modification request message. According to another embodiment, the message for bearer establishment request may be a UE context establishment request message or a UE context modification request message in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station. According to another embodiment, the message for the bearer establishment request may be a bearer context establishment request or a bearer context modification request in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station. According to another embodiment, in case the first node is a source base station in a handover procedure and the second node is a target base station in a handover procedure, the message for bearer establishment request may be a handover request message. According to another embodiment, in case that the first node is a base station that last serves the UE when the UE enters an INACTIVE (INACTIVE) state, and the second node is a base station that the UE newly accesses from the INACTIVE state to an ACTIVE (ACTIVE) state, the message for the bearer establishment request may be an acquire UE context feedback message. It should be understood that the above embodiments are merely examples, and the first node, the second node, and the first message are not limited thereto.

According to one embodiment, the requested PDU session is for supporting SSC, e.g., the requested PDU session may be a new PDU in SSC mode 3, the new PDU session corresponds to an old PDU session, and after the new PDU session is established, the UE may move traffic on the old PDU session to the new PDU session, which is released after a period of time. The first message comprises a PDU session list requesting to be established, each PDU session requesting to be established comprises information related to an old PDU session, and the second node considers the information related to the old PDU session to carry out admission control on GBR QoS flow in the requested PDU session and/or carry out rate control on the QoS flow which is successfully established. The information related to the old PDU session may include at least one of:

-information indicating the SSC pattern (e.g. SSC pattern 3 indication) indicating that the requested PDU session is a PDU session for supporting SSC pattern 3. The second node takes into account said information indicating the SSC pattern when performing admission control and/or rate control of GBR QoS flows in a requested PDU session. In one embodiment, the second node grants the admission of the request for the GBR QoS flow in the requested PDU session, when admission control is performed by the second node, taking into account that the requested PDU session is about to replace an old PDU session, irrespective of whether the second node's existing load plus the GFBR value of the GBR QoS flow in the requested PDU session exceeds the UE-Slice-MBR, if the message for requesting the PDU session includes information indicating the SSC pattern. It should be appreciated that the above examples are merely examples, and that how the second node uses the information indicating the SSC pattern in admission control or rate control is not limited thereto;

-information indicating the old PDU session ID and/or old QoS flow identification (e.g. old PDU session ID and/or old QoS flow identification), indicating the old PDU session associated with the requested PDU session or the QoS flow in the requested PDU session, i.e. the old PDU session the requested PDU session is about to replace, and/or the QoS flow in the old PDU session the requested PDU session is about to replace. The second node takes into account said old PDU session ID and/or old QoS flow identification information for indicating the old PDU session ID and/or the old QoS flow identification information when performing admission control and/or rate control on the GBR QoS flow in the requested PDU session. In one embodiment, the second node grants admission to the requested PDU session if the message requesting the PDU session includes information indicating an old PDU session ID and/or an old QoS flow identification when performing admission control, taking into account that the requested PDU session is about to replace the old PDU session, regardless of whether the second node's existing load plus the GFBR value of the GBR QoS flow in the requested PDU session exceeds the UE-Slice-MBR. In another embodiment, the second node considers whether the existing load plus a certain percentage (e.g., 50%) of the GFBR value of the GBR QoS flow in the requested PDU session exceeds the UE-Slice-MBR when performing admission control on the GBR QoS flow in the requested PDU session, considering that the requested PDU session is about to replace the old PDU session if the message for requesting the PDU session includes information indicating the old PDU session ID and/or the old QoS flow identification when performing admission control, so that after successful admission, the GBR QoS flow of the new PDU session can only be reserved or allocated resources corresponding to the certain percentage of GFBR, while the remaining percentage of resources corresponding to GFBR will be allocated to the GBR QoS flow in the old PDU session corresponding to the GBR QoS flow in the new PDU session. It should be appreciated that the above examples are merely examples and that how the second node uses information indicating the old PDU session ID and/or the old QoS flow identification at admission control or rate control is not limited thereto.

Time information (e.g. lifetime value) indicating the remaining lifetime of the old PDU session, indicating the remaining lifetime value of the old PDU session associated with the requested PDU session, at the end of which the old PDU session is to be released. The second node takes into account the remaining lifetime value of the old PDU session when performing admission control and/or rate control of GBR QoS flows in the requested PDU session. In one embodiment, for example, the remaining lifetime value is less than a particular threshold, the second node agrees to admit the GBR QoS flow in the requested PDU session regardless of whether the second node's existing load plus the GFBR value of the GBR QoS flow exceeds the UE-Slice-MBR. It should be appreciated that the above examples are merely examples and that the second node is not limited to how to use the time information of the remaining lifetime in admission control.

The second node receives the first message. The second node takes into account one or more of the above-mentioned information relating to the old PDU session, controls the GBR QoS flow in the requested PDU session and/or rate controls the QoS flow.

The admission control by the second node is in one embodiment network-Slice admission control, i.e. the second node ensures that the sum of GFBR values of allowed GBR QoS flows does not exceed the UE-Slice maximum bit rate UE-Slice-MBR. In one embodiment, the rate control performed by the second node is network slice rate control, that is, the second node reserves and/or allocates network slice resources for establishing a successful GBR QoS flow. It should be understood that the above embodiments are merely examples, and the types of admission control and rate control are not limited thereto.

And 4C02, the second node sends a second message to the first node. The second message is for feeding back the first message. The second message may include information for feeding back whether the PDU session setup is successful and/or whether the QoS flow setup in the PDU session is successful. According to one embodiment, in case the first node is a core network node and the second node is a base station, the second message may be a PDU session resource establishment feedback message or a PDU session resource modification feedback message or a PDU session resource establishment failure message or a PDU session resource modification failure message. According to another embodiment, in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station, the message for bearer establishment feedback may be a UE context establishment failure message or a UE context establishment feedback message or a UE context modification failure message. According to another embodiment, in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station, the message for bearer establishment feedback may be a bearer establishment failure message or a bearer establishment feedback message or a bearer modification failure message or a bearer modification feedback message. According to another embodiment, in case the first node is a source base station in a handover procedure and the second node is a target base station in a handover procedure, the message for bearer establishment feedback may be a handover request acknowledgement or a handover failure message. It should be understood that the above embodiments are merely examples, and the first node, the second node, and the second message are not limited thereto.

If in step 4C01 the QoS flow admission in the requested PDU session fails, the information included in the second message has the following conditions:

in case 1, for each PDU session resource that is successfully established, if there is a list of QoS flows that have failed to be established, the second message includes the list of QoS flows that have failed to be established and a cause value of the failed establishment of each QoS flow that has failed to be established. If the cause value is a cause related to pre-preemption restriction (pre-preemption limit) or a cause related to network slice admission control failure in the SSC mode 3, a Backoff time (Backoff time) should be included in the second message, which can be a Backoff time predicted by the second node or calculated by the second node. The backoff time may be one for all failed QoS flows or for each failed QoS flow. The backoff time is used for informing the first node of the time when the QoS flow establishment request can be reinitiated, so that the success rate of the re-request is improved.

In case 2, for each PDU session resource failed to be established, a cause value of the failed establishment should be included in the second message, and if the cause value is a cause related to pre-preemption limitation (pre-preemption limitation) or a cause related to network slice admission control failure in the SSC mode 3, a Backoff time (Backoff time) should be included in the second message, and the Backoff time may be a Backoff time predicted by the second node or calculated by the second node. The backoff time may be one for all failed QoS flows or for each requested failed QoS flow. The back-off time is used for informing the first node of the time when the PDU session request can be reinitiated so as to improve the success rate of the reinitiation request.

In case 3, for each requested PDU session resource or requested QoS flow resource in each requested PDU session resource, if the request is temporarily suspended, the second message will include information indicating that the request is temporarily suspended, which may be at least one of the following information:

-a Pending indication (Pending indication) indicating to the first node that the request for said PDU session resources or QoS flow resources in PDU session resources is Pending, such that the first node is continuing to wait for the result of the request;

Fig. 5 shows a method of session establishment and control according to a further exemplary embodiment of the present invention. It should be understood that fig. 5 omits detailed descriptions of steps that are not relevant to the present invention. The method of FIG. 5 includes the steps of:

in step 501, a first node sends a third message to a second node, where the first node is a core network node, or a CU or CU-CP in a base station, the core network node may be an AMF, or an SMF, or an MME, and the second node may be a base station, or a DU or CU-UP in a base station. According to one embodiment, the core network node as the first node may send a third message to the base station as the second node; according to another embodiment, a CU or CU-CP in the base station as the first node may send a third message to the DU in the base station; as another example, a CU-CP in a base station as a first node may send a third message to a CU-UP in a base station as a second node. It should be understood that the above embodiments are merely examples, and the first node and the second node are not limited thereto. The third message is a message for indicating that there are multiple bearer establishment requests to be sent at the same time, and includes related information for indicating that there are multiple bearer establishment requests to be sent at the same time. According to one embodiment, the third message is related to MC traffic, for example, when the MC server is to send a group call, multiple dedicated bearers need to be established at the same time, which is only an example and not a limitation. The third message is sent prior to the plurality of dedicated bearer establishment requests.

The related information for indicating that there are multiple bearer establishment requests to send at the same time may include at least one of the following information:

-requested bearer QoS requirements indicating QoS requirements of an upcoming requested bearer for the second node to prepare resources according to the QoS requirements;

-the requested number of bearers, indicating the number of bearers to be requested, is the number of bearers for the same QoS requirement, so that the second node prepares resources according to the number of bearers and the corresponding QoS requirement;

-requested bearer availability time indicating an upcoming setup time for a bearer, said information being taken into account for reasonable preemption and allocation of resources if the second node is overloaded;

-a requested capacity requirement for indicating capacity information required for the plurality of bearers to be established in order for the second node to prepare resources in advance.

The second node receives the third message.

Step 502, the second node considers the relevant information in the third message for indicating that there are multiple bearer establishment requests to be sent at the same time, and reserves resources for the multiple bearer establishment requests in advance, and if the available resources are not enough, the second node may preempt the resources of other bearers through a pre-preemption function in advance. When the second node prepares the requested resource, the second node sends a fourth message to the first node, where the fourth message is a feedback message of the third message, and the fourth message may include information indicating a result of the resource preparation and/or information related to a sending policy of the multiple bearer establishment requests. The fourth message may be a necessary message or an optional message, that is, if the fourth message is not sent, the first node may consider that the second node is ready for the resource to be requested next, and if the fourth message is sent, the first node may determine how many messages for bearer establishment requests are sent to the second node, considering information indicating a resource preparation result and/or related information of a sending policy of multiple bearer establishment requests in the fourth message, so as to avoid a case of request failure, thereby improving a success rate of multiple bearer establishment requests at the same time.

The information indicating the resource preparation result and/or the related information of the sending policy of the multiple bearer establishment requests may include at least one of the following information:

-a resource preparation success indication for indicating that all requested resources are successfully prepared to inform the first node that multiple requests for bearer establishment can be initiated at any time;

-a resource preparation failure indication for indicating that the requested resource is not successfully prepared to inform the first node that it may fail if multiple requests for bearer establishment are initiated simultaneously;

-information about a transmission policy of a plurality of bearer establishment requests for instructing the first node that the plurality of bearer establishment requests may be transmitted in consideration of the information about the transmission policy when initiating the plurality of bearer establishment requests, which may include: the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time may be, for example, how many bearer establishment requests may be sent at most at the same time each time, and/or how many time intervals of each request are, so as to ensure the success rate of each request.

Step 503, if the first node receives the result information for indicating resource preparation and/or the related information of the sending policy of multiple bearer establishment requests in step 502, the first node sends multiple messages for bearer establishment requests to the second node in consideration of the information.

If the first node does not receive the information in step 502, the first node may consider that the second node is ready for resources, the first node sends multiple messages for bearer establishment request to the second node at the same time, and the second node establishes multiple bearers using the ready resources. The bearer requested to be established is the bearer information indicated in step 501 above.

Therefore, the second node can prepare in advance to establish the resources of the plurality of bearers according to the upcoming plurality of bearer establishment requests, so that request failure caused by resource limitation is avoided, and the success rate of the bearer establishment requests is improved.

According to the method provided by the exemplary embodiment of the application, under the condition that a plurality of load establishing requests related to the key task service exist at the same time and the base station has high load and/or the base station has preemption limitation, the success rate of establishing the key task service is improved, the key task can be smoothly and immediately performed, and the safety of lives and properties is ensured.

Fig. 6 illustrates a method of session establishment and control according to still another exemplary embodiment of the present invention. It should be understood that fig. 6 omits detailed descriptions of steps that are not relevant to the present invention. The method of fig. 6 comprises the steps of:

step 601, the second node sends relevant information for indicating preemption restrictions to the first node, and optionally, the relevant information for indicating preemption restrictions is included in the message for interface establishment or configuration update or the message for load status indication. The first node is a core network node, or a CU or CU-CP in a base station, the core network node may be an AMF or an SMF or an MME, and the second node may be a base station, or a DU or CU-UP in a base station. According to one embodiment, in case the first node is a core network node and the second node is a base station, the message for interface establishment or configuration update is a NG establishment request or a RAN configuration update or a S1 establishment request or an eNB configuration update message. According to another embodiment, the message for interface establishment or configuration update is a F1 interface establishment request or a GNB DU configuration update message, in case the first node is a CU or CU-CP in the base station and the second node is a DU in the base station. According to another embodiment, the message for interface establishment or configuration update is an E1 interface establishment request or GNB CU-UP configuration update message in case the first node is a CU-CP in the base station and the second node is a CU-UP in the base station. It should be understood that the above embodiments are merely examples, and the first node, the second node, and the message for interface establishment or configuration update are not limited thereto.

The message for interface establishment or configuration update includes relevant information for indicating preemption restrictions. The relevant information for indicating preemption restrictions includes information for indicating the number of bearer preemption procedures that can be supported at the second node, for example, 30 preemption procedures per minute, which is exemplary and not limiting.

Step 602, the first node receives the message and the information. When a first node has multiple bearer establishment requests to be initiated simultaneously (e.g., multiple bearer establishment requests for MC traffic), the first node considers relevant information indicating preemption restriction, decides how to send multiple messages for bearer establishment requests to a second node, for example, decides time to send bearer establishment requests and/or number of bearer establishment requests sent each time, and further, for example, the first node may decide to send multiple messages for bearer establishment requests in groups and decides the number of requests sent each group and interval time between two groups of requests sent each time by considering the information, which is only an example and not a limitation. By considering the bearer establishment request sent by the information, the condition of request failure can be avoided, so that the success rate of a plurality of bearer establishment requests for the MC service is improved, and the smooth operation of the MC service is ensured.

According to the method provided by the exemplary embodiment of the application, the establishment success rate of the mission critical service can be improved and the mission critical service can be smoothly and immediately performed under the conditions that a plurality of bearer establishment requests related to the mission critical service exist at the same time and the base station has high load and/or the base station has preemption limitation.

Various exemplary embodiments of the present invention have been described above based on fig. 3 to 6, but it should be understood that features, functions, steps, operations, or any combination thereof described in any one embodiment of the present invention may be replaced by or combined with features, functions, steps, operations, or any combination thereof described in other embodiments.

Fig. 7 shows a block diagram of a first node according to an exemplary embodiment of the present invention.

Referring to fig. 7, a first node 700 may include a controller 701 and a transceiver 706. According to an embodiment of the present invention, the controller 701 may be defined as a circuit application specific integrated circuit or at least one processor. The controller 701 may control the overall operation of the first node and control the first node to implement the various methods set forth in the present invention.

The transceiver 706 may transmit/receive signals to/from other network entities (such as, but not limited to, a second node) over a wired or wireless link. For example, the transceiver 706 may transmit signals to and receive signals from the second node.

It should be understood that not all of the components shown are necessary. The first node 700 may be implemented with more or fewer components than those shown in fig. 7. According to one embodiment, the controller 701 and the transceiver 706 may be implemented as a single chip. According to another embodiment, the controller 701 and the transceiver 706 may be implemented as separate chips, respectively.

The first node may be a core network node, which may be an AMF or an SMF or an MME, or a CU or CU-CP in a base station.

Fig. 8 shows a block diagram of a second node according to an exemplary embodiment of the present invention.

Referring to fig. 8, a second node 800 may include a controller 801 and a transceiver 806. According to an embodiment of the invention, the controller 801 may be defined as a circuit application specific integrated circuit or at least one processor. The controller 801 may control the overall operation of the second node and control the second node to implement the various methods set forth in the present invention.

The transceiver 806 may transmit/receive signals to/from other network entities (such as but not limited to a first node) over a wired or wireless link. For example, transceiver 806 may transmit signals to and receive signals from a first node.

It should be understood that not all of the components shown are necessary. The second node 800 may be implemented with more or fewer components than those shown in fig. 8. According to one embodiment, the controller 801 and the transceiver 806 may be implemented as a single chip. According to another embodiment, the controller 801 and the transceiver 806 may be implemented as separate chips, respectively.

The second node may be a base station or a DU or CU-UP in a base station.

Those of skill in the art would understand that the various illustrative logical blocks, modules, circuits, and steps described in this application may be implemented as hardware, software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The various illustrative logical blocks, modules, and circuits described herein may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The steps of a method or algorithm described in this application may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

In one or more exemplary designs, the functions may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

The examples of the present application are only for the purpose of easy description and to help comprehensive understanding of the present application, and are not intended to limit the scope of the present application. Therefore, it should be understood that all modifications and changes or forms of modifications and changes derived from the technical idea of the present application other than the embodiments disclosed herein fall within the scope of the present application.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the scope of the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A method performed by a second node in a wireless communication system, the method comprising:

receiving a message for bearer establishment request from a first node;

and sending a message for bearing the establishment feedback to the first node.

2. The method of claim 1, wherein the message for bearer establishment feedback comprises information indicating a backoff time if the second node determines that the requested bearer establishment failed.

3. The method of claim 1, wherein the message for bearer establishment feedback comprises information indicating that a suspension is requested if the second node determines that the requested bearer is temporarily unable to be established.

4. The method of claim 3, wherein the information indicating that the request is pending further comprises at least one of a pending indication and a pending time.

5. A method performed by a first node in a wireless communication system, the method comprising:

sending a message for bearing a building request to a second node;

a message for bearer establishment feedback is received from the second node.

6. The method of claim 5, wherein the message for bearer establishment feedback comprises information indicating a backoff time if the second node determines that the requested bearer establishment failed;

7. the method of claim 5, wherein the message for bearer establishment feedback comprises information indicating a request to suspend if the second node determines that the requested bearer cannot be established temporarily.

8. A method performed by a second node in a wireless communication system, the method comprising:

receiving a message from a first node indicating that there are multiple bearer establishment requests to send simultaneously;

based on the message, resources for establishing a plurality of bearers are prepared.

9. The method of claim 8, wherein the message indicating that there are multiple bearer establishment requests to send simultaneously comprises at least one of:

requested bearer quality of service, qoS, requirements;

the number of requested bearers;

requested bearer availability time;

requested capacity requirements.

10. The method of claim 8, further comprising: sending a feedback message to the first node;

the feedback message comprises information indicating resource preparation results and/or information related to a transmission policy of a plurality of bearer establishment requests.

11. The method of claim 10, wherein,

the information for indicating the resource preparation result and/or the related information of the sending strategy of the plurality of bearer establishment requests comprises at least one of the following information:

a resource preparation success indication;

a resource preparation failure indication;

the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time.

12. A method performed by a first node in a wireless communication system, the method comprising:

receiving from the second node relevant information indicating preemption restrictions,

the first node sends a message for a bearer establishment request taking into account said relevant information for indicating preemption restrictions.

13. The method of claim 12, wherein the relevant information for indicating preemption restrictions comprises relevant information for indicating a number of bearer preemption procedures that can be supported at the second node.

14. The method of claim 12, wherein sending a message for a bearer setup request based on the relevant information indicating preemption restrictions further comprises:

the first node considers the relevant information for indicating the preemption limitation and decides the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time;

and sending the message for the bearer establishment request based on the time for sending the bearer establishment request and/or the number of the bearer establishment requests sent each time.

15. A method performed by a second node in a wireless communication system, the method comprising:

sending to the first node relevant information indicating preemption restrictions,

a message for a bearer establishment request is received from a first node.