CN112243300B

CN112243300B - Connection establishment method and device

Info

Publication number: CN112243300B
Application number: CN201910656193.9A
Authority: CN
Inventors: 韦安妮; 金晨光
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2019-07-19
Filing date: 2019-07-19
Publication date: 2022-11-08
Anticipated expiration: 2039-07-19
Also published as: CN112243300A

Abstract

The invention provides a connection establishment method and device, and belongs to the technical field of wireless communication. The connection establishment method is applied to a terminal, the terminal is positioned in the coverage range of a first communication mode network and/or a second communication mode network, and the method comprises the following steps: establishing a first session with a first communication mode network side device; acquiring indication information of the first communication mode network side equipment, wherein the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and second communication mode network side equipment before the first session is interrupted; and before the first session is interrupted, establishing a transmission layer path between the first session and the network side equipment in the second communication mode. By the technical scheme of the invention, the problem of service interruption caused by incapability of maintaining the IP address in a simple and independent core network configuration scene can be solved.

Description

Connection establishment method and device

Technical Field

The present invention relates to the field of wireless communications technologies, and in particular, to a connection establishment method and apparatus.

Background

In some scenarios, in order to simplify configuration, two independent core networks (4G core network and 5G core network) are respectively deployed in a core network, and there is no interface intercommunication between the two networks, and the two networks independently carry 4G and 5G services.

In the Data transmission process, if the terminal moves from a 5G coverage area to a 4G coverage area, the terminal provides 5G PS Data connection at the 5G, the quality of a 5G wireless signal is deteriorated, a New Radio (NR) link is released, a bottom layer reports interruption of a 5G Protocol Data Unit (PDU) Session (Session) to an upper layer, the upper layer of the terminal senses the interruption of the 5G PDU Session, the upper layer determines to start the 4G Session through self-capability and current other wireless connection states, and the upper layer of the terminal starts to rebuild the service of a previously interrupted application layer on the newly-built 4G Session. If the terminal moves from the 4G coverage area to the 5G coverage area, the quality of 4G wireless signals is deteriorated, a Long Term Evolution (LTE) link is released, a bottom layer reports 4G Session interruption to an upper layer, after the upper layer of the terminal senses the 4G Session interruption, the upper layer determines to start the 5G PDU Session through self-capability and current other wireless connection states, and the terminal application initiates reestablishment of the service of the previously interrupted application layer on the 5G PDU Session established by the upper layer. In the process, because of simple independent core network configuration, the IP address of the session cannot be maintained, and the session is re-initiated in another network again by the application layer after one network is interrupted. The problems caused by the reestablishment after the session is interrupted are as follows:

1. the session is interrupted, and the application layer has no session recovery mechanism, so that the user experience is directly influenced;

2. the session is interrupted, and the application layer has a session recovery mechanism, but the user experience is directly reduced due to the time delay introduced by the new establishment of a Transmission Control Protocol (TCP) link of a new network and the reduction of throughput caused by the slow start of the TCP.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a connection establishment method and apparatus, which can solve the problem of service interruption caused by an incapability of maintaining an IP address in a simple and independent core network configuration scenario.

To solve the above technical problem, embodiments of the present invention provide the following technical solutions:

the embodiment of the invention provides a connection establishment method, which is applied to a terminal, wherein the terminal is positioned in the coverage range of a first communication mode network and/or a second communication mode network, and the method comprises the following steps:

establishing a first session with a first communication mode network side device;

acquiring indication information of the first communication mode network side equipment, wherein the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and second communication mode network side equipment before the first session is interrupted;

and before the first session is interrupted, establishing a transmission layer path between the first session and the network side equipment in the second communication mode.

Optionally, the indication information indicates that the first communication mode network and the second communication mode network are networked independently and do not interface with each other.

Optionally, the obtaining the indication information of the first communication mode network side device includes:

and acquiring the indication information in the process of establishing the first session or attaching the first communication mode network.

Optionally, the establishing a first session with a network side device in a first communication mode, where the obtaining the indication information in the process of establishing the first session includes:

sending a session establishment request to the first communication mode network side equipment;

and receiving a session establishment request response of the first communication mode network side equipment, wherein the session establishment request response carries the indication information.

Optionally, the obtaining the indication information in the process of attaching to the first communication mode network includes:

sending an attachment request to the first communication mode network side equipment;

and receiving an attach request response of the first communication mode network side equipment, wherein the attach request response carries the indication information.

Optionally, before the first session is established with the network-side device in the first communication mode, the method further includes:

sending a session establishment request to the first communication mode network side equipment, wherein the session establishment request indicates that a session mode is SSC1;

receiving a session establishment rejection request of the first communication mode network side equipment, wherein the session establishment rejection request carries a cause value or a session mode SSC3;

and sending a session establishment request again to the first communication mode network side equipment, wherein the session establishment request indicates that the session mode is SSC3.

Optionally, the first session is an SSC3 session.

Optionally, before sending the session establishment request to the first communication mode network side device, the method further includes:

detecting that the signal strength of the first communication mode network is greater than the signal strength of the second communication mode network.

Optionally, the establishing a transport layer path with a second communication mode network side device before the first session is interrupted includes:

detecting signal strengths of the first communication mode network and the second communication mode network;

when the signal intensity of the second communication mode network is greater than a first threshold value, establishing a second session with the second communication mode network side equipment, and establishing a transmission layer path between the second communication mode network side equipment and the second communication mode network side equipment;

releasing the first session when the signal strength of the first communication mode network is less than a second threshold, the second threshold being less than the first threshold.

Optionally, the establishing a transport layer path between the network side device and the second communication mode includes:

when a transmission layer supports multi-path transmission, establishing a new transmission sub-flow between the second communication mode network side equipment and the second communication mode network side equipment;

and when the transport layer does not support multipath transmission, establishing a new TCP connection between the second communication mode network side equipment and the second communication mode network side equipment.

The embodiment of the invention also provides a connection establishment method, which is applied to network side equipment in a first communication mode and/or a second communication mode, and the method comprises the following steps:

and sending indication information to a terminal in a coverage range, wherein the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and the second communication mode network side equipment before the first session between the terminal and the first communication mode network side equipment is interrupted.

Optionally, the sending the indication information to the terminal in the coverage includes:

and sending the indication information to the terminal in a session establishment process between the terminal and the network side equipment or an attachment process of the terminal.

Optionally, sending the indication information to the terminal in a session establishment procedure between the terminal and the network side device includes:

receiving a session establishment request of the terminal;

and sending a session establishment request response to the terminal, wherein the session establishment request response carries the indication information.

Optionally, sending the indication information to the terminal in the attach process of the terminal includes:

receiving an attachment request of the terminal;

and sending an attachment request response to the terminal, wherein the attachment request response carries the indication information.

Optionally, the method further comprises:

receiving a session establishment request of the terminal, wherein the session establishment request indicates that a session mode is SSC1;

sending a session establishment rejection request to the terminal, wherein the session establishment rejection request carries a cause value or a session mode SSC3;

and receiving a session establishment request sent again by the terminal, wherein the session establishment request indicates that the session mode is SSC3.

The embodiment of the invention also provides a connection establishing device, which is applied to a terminal, wherein the terminal is positioned in the coverage range of a first communication mode network and/or a second communication mode network, the device comprises a processor and a transceiver,

the processor is used for establishing a first session with a first communication mode network side device;

the transceiver is configured to acquire indication information of the first communication mode network side device, where the indication information is used to indicate that the terminal establishes a transport layer path with a second communication mode network side device before the first session is interrupted;

the processor is further configured to establish a transport layer path with a second communication mode network side device before the first session is interrupted.

Optionally, the transceiver is specifically configured to acquire the indication information in the first session establishment procedure or in the first communication mode network attachment procedure.

Optionally, the transceiver is specifically configured to send a session establishment request to the first communication mode network side device; and receiving a session establishment request response of the first communication mode network side equipment, wherein the session establishment request response carries the indication information.

Optionally, the transceiver is specifically configured to send an attach request to the first communication mode network side device; and receiving an attach request response of the first communication mode network side equipment, wherein the attach request response carries the indication information.

Optionally, the transceiver is further configured to send a session establishment request to the first communication mode network side device, where the session establishment request indicates that a session mode is SSC1; receiving a session establishment rejection request of the first communication mode network side equipment, wherein the session establishment rejection request carries a cause value or a session mode SSC3; and sending a session establishment request again to the first communication mode network side equipment, wherein the session establishment request indicates that the session mode is SSC3.

Optionally, the first session is an SSC3 session.

Optionally, before the transceiver sends a session establishment request to the first communication mode network side device, the processor detects that the signal strength of the first communication mode network is greater than the signal strength of the second communication mode network.

Optionally, the processor is specifically configured to detect signal strengths of the first communication mode network and the second communication mode network; when the signal intensity of the second communication mode network is greater than a first threshold value, establishing a second session with the second communication mode network side equipment, and establishing a transmission layer path between the second communication mode network side equipment and the second communication mode network side equipment; releasing the first session when the signal strength of the first communication mode network is less than a second threshold, the second threshold being less than the first threshold.

Optionally, the processor is specifically configured to establish a new transport sub-stream with the network side device in the second communication mode when a transport layer supports multipath transmission; and when the transport layer does not support multipath transmission, establishing a new TCP connection between the second communication mode network side equipment and the second communication mode network side equipment.

The embodiment of the invention also provides a connection establishing device, which is applied to network side equipment in a first communication mode and/or a second communication mode, the device comprises a processor and a transceiver,

the transceiver is used for sending indication information to a terminal in a coverage range, and the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and a second communication mode network side device before a first session between the terminal and the first communication mode network side device is interrupted.

Optionally, the transceiver is specifically configured to send the indication information to the terminal in a session establishment procedure between the terminal and the network side device or in an attach procedure of the terminal.

Optionally, the transceiver is specifically configured to receive a session establishment request of the terminal; and sending a session establishment request response to the terminal, wherein the session establishment request response carries the indication information.

Optionally, the transceiver is specifically configured to receive an attach request of the terminal; and sending an attachment request response to the terminal, wherein the attachment request response carries the indication information.

Optionally, the transceiver is further configured to receive a session establishment request of the terminal, where the session establishment request indicates that a session mode is SSC1; sending a session establishment rejection request to the terminal, wherein the session establishment rejection request carries a cause value or a session mode SSC3; and receiving a session establishment request sent again by the terminal, wherein the session establishment request indicates that the session mode is SSC3.

An embodiment of the present invention further provides a communication device, including: memory, a processor and a computer program stored on the memory and executable on the processor, which computer program, when executed by the processor, carries out the steps of the connection establishment method as described above.

An embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps in the connection establishment method described above are implemented.

The embodiment of the invention has the following beneficial effects:

in the scheme, the network side indicates the terminal to establish a bottom layer dual-channel for the service in advance before the single network session is interrupted, and the establishment of the transmission layer multi-channel is triggered, so that the service experience without reconnection delay of the service without interruption due to IP change can be provided for the terminal, and the problem of service interruption caused by incapability of maintaining an IP address under a simple and independent core network configuration scene is solved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

FIG. 1 is a schematic diagram of a protocol stack of TCP;

FIG. 2 is a diagram of a protocol stack of MPTCP;

FIG. 3 is a schematic diagram of MPTCP dual paths;

FIG. 4 is a schematic diagram of a QUIC dual path;

FIG. 5 is a diagram of an interworking architecture with an N26 interface;

FIG. 6 is an interworking architecture diagram without the N26 interface;

FIG. 7 is a diagram of a standalone networking mode in a simple configuration;

fig. 8 is a flowchart illustrating a connection establishment method applied to a terminal according to an embodiment of the present invention;

fig. 9 is a flowchart illustrating a connection establishment method applied to a network-side device according to an embodiment of the present invention;

fig. 10 is a schematic diagram illustrating a terminal moving process according to an embodiment of the present invention;

fig. 11 is a schematic diagram illustrating a network side sending an indication message of simplifying configuration of independent networking according to an embodiment of the present invention;

FIG. 12 is a schematic diagram of a dual path setup according to an embodiment of the present invention;

fig. 13 is a schematic diagram of session mode negotiation between a terminal and a network side according to an embodiment of the present invention;

FIG. 14 is a schematic diagram illustrating the establishment of dual paths according to one embodiment of the present invention;

fig. 15 is a schematic diagram of a moving process of a third terminal according to an embodiment of the present invention;

fig. 16 and fig. 17 are schematic diagrams illustrating establishment of three dual channels according to an embodiment of the present invention;

fig. 18 is a schematic diagram of a four-terminal moving process according to an embodiment of the present invention;

fig. 19 and fig. 20 are schematic diagrams of establishing four dual channels according to an embodiment of the present invention;

fig. 21 is a block diagram showing a configuration of a connection establishing apparatus applied to a terminal according to an embodiment of the present invention;

fig. 22 is a block diagram of a connection establishing apparatus applied to a network side device according to an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages to be solved by the embodiments of the present invention clearer, the following detailed description is made with reference to the accompanying drawings and specific embodiments.

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be implemented in sequences other than those illustrated or described herein. Moreover, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. In the description and in the claims "and/or" means at least one of the connected objects.

The techniques described herein are not limited to Long Term Evolution (LTE)/LTE Evolution (LTE-Advanced) systems, and may also be used for various wireless communication systems, such as Code Division Multiple Access (CDMA), time Division Multiple Access (TDMA), frequency Division Multiple Access (FDMA), orthogonal Frequency Division Multiple Access (OFDMA), single-carrier Frequency-Division Multiple Access (SC-FDMA), and other systems. The terms "system" and "network" are often used interchangeably. CDMA systems may implement Radio technologies such as CDMA2000, universal Terrestrial Radio Access (UTRA), and so on. UTRA includes Wideband CDMA (Wideband Code Division Multiple Access, WCDMA) and other CDMA variants. TDMA systems may implement radio technologies such as Global System for Mobile communications (GSM). The OFDMA system may implement radio technologies such as Ultra Mobile Broadband (UMB), evolved-UTRA (E-UTRA), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, flash-OFDM, etc. UTRA and E-UTRA are parts of the Universal Mobile Telecommunications System (UMTS). LTE and LTE-advanced (e.g., LTE-A) are new UMTS releases that use E-UTRA. UTRA, E-UTRA, UMTS, LTE-A, and GSM are described in documents from an organization named "third Generation Partnership project" (3 rd Generation Partnership project,3 GPP). CDMA2000 and UMB are described in documents from an organization named "third generation partnership project 2" (3 GPP 2). The techniques described herein may be used for both the above-mentioned systems and radio technologies, as well as for other systems and radio technologies. However, the following description describes NR systems for purposes of example, and NR terminology is used in much of the description below, although the techniques may also be applied to applications other than NR system applications.

The following description provides examples and does not limit the scope, applicability, or configuration set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the spirit and scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For example, the described methods may be performed in an order different than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

Multipath TCP (MPTCP) allows a TCP connection to use multiple paths to maximize channel resource usage. The core idea of MPTCP is to define a way to establish a connection between two hosts, rather than between two interfaces. In TCP, a connection is established between two IP addresses, each TCP connection identified by a quadruplet of addresses and ports identifying a source and a destination. In view of this limitation, an application can only create one TCP connection through a single connection, and therefore, it may happen that multiple connections may be simultaneously established between two hosts, but only a single connection is used by a certain application at the same time, while the multiproath TCP allows the connection to use multiple paths at the same time, and for this reason, the multiprocess TCP creates a TCP connection called a flow on each path that needs to be used, fig. 1 and fig. 2 are schematic diagrams of protocol stacks of TCP and MPTCP, respectively, and fig. 3 is a schematic diagram of dual paths of MPTCP.

Fast UDP Internet Connection (QUIC) is a low-latency Internet transport layer Protocol based on a User Datagram Protocol (UDP), and the QUIC implements packet aggregation by using a Connection ID of a QUIC packet header to support multipath, and fig. 4 is a schematic diagram of a QUIC dual path.

The relevant communication standards define three session modes: session and Service Continuity (SSC) 1, SSC2 and SSC3. The mode of the Session is determined by negotiation between a terminal (UE) and a core network when the Session is established, the UE provides the Session mode, but the final determined Session mode is determined by a Session Management Function (SMF).

SSC1 session means that from the beginning to the end of the session, the UPF anchor point of the session does not change, and for IPV4 or IPV6 services, the IP address can remain unchanged. An SSC2 session refers to a session that can be re-established after release. The SSC3 session refers to establishing a new session before an old session is released and then releasing the old session for a certain time.

As shown in fig. 5, in an interworking scenario defined by the related communication standards, the SMF of the 5G Core network (5 GC), the Policy Control Function Entity (PCF), the User Plane Function Entity (UPF, user Plane Function), the Unified Data Management (UDM) and the public Data network Gateway Control Plane (PDN Gateway-C, PGW-C) of the 4G Core network (EPC), the Policy and Charging Control Entity (Policy and Charging Function, PCRF), the public Data network Gateway User Plane (PDN Gateway-U, PGW-U), the Home Subscriber Server (Home Subscriber Server, HSS) are jointly configured, but an optional interface 26 is provided between the Mobility Management Entity (MME) and the Mobility Management Function Entity (AMF, mobility Management and Mobility Function) is provided.

Under the condition of an N26 architecture, 4G and 5G core networks are tightly coupled, and a 5GC AMF and an EPC MME are communicated through an N26 interface; in the interoperation process, the core networks of the source side and the target side transmit the context and the session information of the UE through the N26 interface, and switch the context and the session resources of the UE to the target side, so that the IP address and the service continuity are maintained.

In the interworking architecture scenario without an N26 interface as shown in fig. 6, there is no interworking interface between the 5GC and the EPC, and in the interworking process, the target side core network obtains information such as a gateway address of the UE at the source side through the UE, and the UE initiates reestablishment of a UE context and session resources at the target side, keeping the UE IP address unchanged.

The interworking scenario defined by the relevant communication standard is limited to the tight coupling between the 4G and 5G core networks, whether context is transferred via N26 or saved via UE, because the combination of UPF and PGW can achieve the purpose of IP address invariance.

In some scenarios, to simplify the configuration, as shown in fig. 7, two sets of independent core networks (LTE EPC and 5 GC) are respectively deployed in the core network, and there is no interface intercommunication between the core networks, and the two networks independently carry 4G and 5G services. In 4G LTE and 5G NR wireless networks, handover, network reselection are not configured.

In the data transmission process, if the terminal moves from a 5G coverage area to a 4G coverage area, the terminal provides 5G PS data connection at 5G, the quality of 5G wireless signals deteriorates, an NR link is released, a bottom layer reports 5G PDU Session interruption to an upper layer, the upper layer of the terminal senses the 5G PDU Session interruption, the upper layer determines to start 4G Session through self-capability and current other wireless connection states, and the upper layer of the terminal initiates reestablishment of the previously interrupted application layer service on the newly-established 4G Session. If the terminal moves from the 4G coverage area to the 5G coverage area, the quality of 4G wireless signals deteriorates, an LTE link is released, a bottom layer reports 4G Session interruption to an upper layer, after the upper layer of the terminal senses the 4G Session interruption, the upper layer determines to start the 5G PDU Session through the self-capability and the current other wireless connection states, and the upper layer of the terminal initiates reestablishment of the service of the previously interrupted application layer on the newly established 5G PDU Session. In the process, because of simple and independent core network configuration, the IP address of the session cannot be maintained, and the session is re-initiated in another network again by the application layer after one network is interrupted. The problems associated with this session reestablishment after interruption are:

2. the session is interrupted, the application layer has a session recovery mechanism, but the user experience is directly reduced due to the time delay introduced by the new establishment of the TCP link of the new network and the reduction of the throughput caused by the slow start of the TCP.

In order to solve the above problem, embodiments of the present invention provide a connection establishment method and apparatus, which can solve the problem of service interruption caused by an inability to maintain an IP address in a simple and independent core network configuration scenario.

An embodiment of the present invention provides a connection establishment method, which is applied to a terminal, where the terminal is located in a coverage area of a first communication mode network and/or a second communication mode network, as shown in fig. 8, and the method includes:

step 101: establishing a first session with a first communication mode network side device;

step 102: acquiring indication information of the first communication mode network side equipment, wherein the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and second communication mode network side equipment before the first session is interrupted;

step 103: and before the first session is interrupted, establishing a transmission layer path between the first session and the network side equipment in the second communication mode.

In this embodiment, the network side instructs the terminal to establish a bottom dual-path for the service in advance before a single network session is interrupted, and triggers the establishment of the transmission layer multi-path, so that the service experience without reconnection delay can be provided for the terminal with an IP change but without service interruption, and the problem of service interruption caused by an incapability of maintaining an IP address in a simple and independent core network configuration scene is solved.

In a specific embodiment, the establishing a first session with a first communication mode network side device, and the acquiring the indication information in the establishing of the first session includes:

In another specific embodiment, the acquiring the indication information in the process of attaching to the first communication mode network includes:

and receiving an attach request response of the first communication mode network side device, wherein the attach request response carries the indication information.

Optionally, before the establishing the first session with the first communication mode network-side device, the method further includes:

If the SSC mode in the session establishment request of the UE is SSC1, the SMF which simplifies and configures the independent network needs to reject the session establishment request and carries a reason value, or directly replies to SSC3 to indicate the UE to consider whether to reinitiate the session establishment request through the SSC3 mode.

Optionally, the first session is an SSC3 session.

Optionally, the establishing a transport layer path with the second communication mode network side device includes:

when the transmission layer supports multi-path transmission, establishing a new transmission sub-flow between the second communication mode network side equipment and the transmission layer;

and when the transport layer does not support multipath transmission, establishing a new TCP connection with the second communication mode network side equipment.

Specifically, the first communication mode may be one of 4G and 5G, and the second communication mode may be the other of 4G and 5G. The terminal can detect the signal intensity in real time according to the indication information acquired from the core network, and when the terminal moves from the single coverage area to the 4G and 5G double coverage areas and the signal reaches a set threshold value, the terminal initiates session establishment for the session in the original network in a new network to form a double channel. The UE triggers a transmission layer to initiate double-flow establishment after double-paths of a bottom layer are established for a session by 4G and 5G, if the transmission layer supports multipath transmission, new transmission sub-flows are triggered, for example, a new TCP sub-flow is added to MPTCP, a new sub-path is added to QUIC, if the transmission layer does not support multipath, if the traditional TCP service is adopted, new TCP connection is directly initiated, application layer data is waited to be issued, and then the new TCP is used for sending data.

In addition, the UE may also determine whether to initiate or switch to an SSC1 session establishment in a simplified configuration independent networking based on application layer interactions or configurations.

An embodiment of the present invention further provides a connection establishment method, which is applied to a network device in a first communication mode and/or a second communication mode, and as shown in fig. 9, the method includes:

step 201: and sending indication information to a terminal in a coverage range, wherein the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and the second communication mode network side equipment before the first session between the terminal and the first communication mode network side equipment is interrupted.

Optionally, the indication information indicates that the first communication mode network and the second communication mode network are independently networked and do not interface with each other.

Optionally, the sending the indication information to the terminals within the coverage area includes:

In a specific embodiment, sending the indication information to the terminal in the session establishment procedure between the terminal and the network side device includes:

receiving a session establishment request of the terminal;

In another specific embodiment, the sending the indication information to the terminal in the attach process of the terminal includes:

receiving an attachment request of the terminal;

Optionally, the method further comprises:

Specifically, the first communication mode may be one of 4G and 5G, and the second communication mode may be the other of 4G and 5G. When a 5G session is established, the 5G core network sends indication information to the UE, the network accessed by the UE is indicated to configure independent networking for simplification, and the indication information is used for the UE to detect the strength of 4G and 5G signals in real time and initiate double connection; when the UE is attached to the 4G core network, the network accessed by the UE is indicated to configure independent networking for simplification, and the indication information is used for the UE to detect the strength of 4G and 5G signals in real time according to the indication and initiate double connection.

The technical scheme of the invention is further described by combining the specific embodiments as follows:

the first embodiment is as follows:

as shown in fig. 10, when the UE initiates session establishment at the point a covered by the 5G network, as shown in fig. 11, the 5G core network carries indication information in a response to the session establishment request, which indicates that the network to which the UE accesses is an independent network configured for simplification, and the UE can detect the strength of the 4G and 5G signals in real time according to the indication information, and initiate dual connectivity.

As shown in fig. 12, when the UE moves from point a covered by 5G alone to point B covered by 4G and 5G in dual coverage, all sessions are unified to initiate session establishment at 4G, and form a dual path with a 5G session that has not been disconnected. The process is as follows:

step 1, establishing 5G session 1 between UE and a 5G core network, wherein the IP address is IP1;

step 2, the UE monitors signals according to the indication information received from the network side, and detects that the 4G signal strength reaches a certain threshold value

Step 3, UE initiates 4G session establishment, and the IP address is IP2;

step 4, UE triggers the transmission layer to initiate double-flow establishment, if the transmission layer supports multipath transmission, triggers a newly-established transmission sub-flow, for example, MPTCP adds a new TCP sub-flow, QUIC adds a new sub-path, if the transmission layer does not support multipath, as traditional TCP service, directly initiates a new TCP connection, waits for the down-sending of application layer data, and then uses the newly-established TCP to send data;

and step 5, when the UE detects that the 5G signal is continuously weakened to the set threshold value, releasing the 5G session 1.

The second embodiment:

in this embodiment, judgment of the session mode is added. Since the IP address changes regardless of the session mode of SSC1, the UE can only switch to SSC3 session mode, or if the UE continues to use SSC1 session mode, the network can only currently provide best effort service, and for SSC2 session mode, the IP address change and session interruption are of little consequence, so no special handling is needed.

When UE initiates session establishment at point A covered by 5G independently, if SSC mode in session establishment request of UE is SSC1, SMF of simplified configuration independent network needs to reject session establishment request and carries reason value, or directly replies SSC3 to indicate UE whether to re-initiate session establishment request through SSC3 mode. As shown in fig. 13, the specific process includes the following steps:

step 1, UE sends a session establishment request to SMF, wherein the session establishment request carries PDU session ID and indicates that an SSC mode is SSC1;

step 2, the SMF determines that the network can not support SSC1 session, and the network is a simplified configuration independent network;

step 3, the SMF sends a session establishment rejection request to the UE, wherein the session establishment rejection request carries a reason value or replies SSC3 to indicate the UE to consider whether to reinitiate the session establishment request through the SSC3 mode;

step 4, the UE judges whether to terminate the session request or continue to request SSC1 or establish the session by using SSC3;

step 5a, UE can send a session establishment request to SMF, wherein the session establishment request carries PDU session ID and indicates SSC mode as SSC1;

step 5b, the UE may also send a session establishment request to the SMF, where the session establishment request carries the PDU sessionID and indicates that the SSC pattern is SSC3.

As shown in fig. 10, the UE moves from point a covered by 5G alone to point B covered by 4G, 5G double. At this point, the UE detects the 4G signal, registers at 4G when the signal strength reaches a certain threshold (which may be greater than or equal to the threshold set for a 5G to 4G handover), determines all SSC3 mode sessions currently in the 5G network, and then initiates session establishment at 4G for these SSC3 sessions, forming a dual path with the not yet disconnected 5G sessions. When the 5G signal continues to fade to a session interruption, the service is not interrupted despite the IP address change for the SSC3 session because of the establishment of the 4G session. As shown in fig. 14, the process includes the following steps:

step 1, establishing a 5G session 1 between the UE and a 5G core network, wherein the session mode is SSC3, and the IP address is IP1;

step 2, the UE monitors signals and detects that the 4G signal strength reaches a certain threshold value

Step 3, the UE registers in the 4G and initiates the establishment of a 4G session, wherein the IP address is IP2;

step 4, UE triggers the transmission layer to initiate double-flow establishment, if the transmission layer supports multi-path transmission, triggers new transmission sub-flow, for example, MPTCP adds a new TCP sub-flow, QUIC adds a new sub-path;

and 5, when the UE detects that the 5G signal is continuously weakened to the set threshold value, releasing the 5G session 1.

Example three:

as shown in fig. 15, when a UE establishes a new session in a 4G coverage area and a 5G coverage area, such as point C, an alternative method is as follows:

the method comprises the following steps: the UE initiates session establishment at the 4G and the 5G simultaneously, and prevents session interruption when the UE moves from a point C of a 4G and 5G double coverage area to a point D of a 4G single coverage area or from a point C of the 4G and 5G double coverage area to a point E of a 5G single coverage area.

The second method comprises the following steps: when a session is newly established by the UE in the 4G and 5G dual coverage areas, such as point C, the signal strength is determined, if the 5G signal is strong, the session is established in 5G, when the UE moves from the point C in the 4G and 5G dual coverage areas to point D in the 4G single coverage area, the 4G signal strength is detected, and when a certain threshold is reached, the session establishment is initiated in 4G, as shown in fig. 16, the process includes the following steps:

step 0, the UE detects that the 5G signal intensity is larger than the 4G signal intensity;

step 1, establishing a 5G session between the UE and a 5G core network, wherein the IP address is IP1;

Step 3, the UE registers in the 4G and initiates 4G session establishment, wherein the IP address is IP2;

step 4, UE triggers the transmission layer to initiate double-flow establishment, if the transmission layer supports multipath transmission, then triggers a newly-established transmission sub-flow, for example, MPTCP adds a new TCP sub-flow, QUIC adds a new sub-path, if the transmission layer does not support multipath, as in the traditional TCP service, then directly initiates a new TCP connection, waits for the down-sending of application layer data, and then uses the newly-established TCP to send data;

If the 4G signal is strong, a session is established in 4G, when the UE moves from a point C of a 4G, 5G dual coverage area to a point E of a 4G single coverage area, the 5G signal strength is detected, and when a certain threshold is reached, session establishment is initiated in 5G, as shown in fig. 17, the flow includes the following steps:

step 0, the UE detects that the 4G signal intensity is greater than the 5G signal intensity;

step 1, establishing 4G session 1 between UE and a 4G core network, wherein the IP address is IP1;

step 2, the UE monitors signals and detects that the 5G signal strength reaches a certain threshold value

Step 3, UE initiates 5G session establishment, and the IP address is IP2;

and step 5, when the UE detects that the 4G signal is continuously weakened to the set threshold value, releasing the 4G session 1.

Example four:

as shown in fig. 18, when the UE initiates session establishment at the point F covered by the 4G alone, the core network carries indication information in a response sent to the UE in an Attach (Attach) procedure, which indicates the UE to access the network for simplifying configuration independent networking, so that the UE detects the strength of the 4G and 5G signals in real time according to the indication, and initiates dual connectivity, as shown in fig. 19, the procedure includes the following steps:

step 1, UE initiates an Attach flow to MME;

step 2, GW determines the network, which is a simplified configuration independent network;

and 3, the MME sends indication information to the UE to indicate a network accessed by the UE to simplify and configure independent networking.

As shown in fig. 18, when the UE moves to a point G with dual coverage of 4G and 5G in a 4G single coverage area, such as a point F, and the UE detects that the 5G signal strength reaches a certain threshold according to the indication information sent by the network, the UE initiates session establishment in 5G in the 4G network, and forms a dual path with the 4G session that is not yet disconnected. As shown in fig. 20, the process includes the following steps:

step 1, establishing a 4G session 1 between the UE and a 4G core network;

step 2, the UE monitors signals according to the indication information received from the network side and detects that the 5G signal strength reaches a certain threshold value

Step 3, the UE registers in the 5G network and initiates the establishment of a 5G session, wherein the IP address is IP2;

and 5, when the UE detects that the 4G signal is continuously weakened to the set threshold value, releasing the 4G session 1.

An embodiment of the present invention further provides a connection establishing apparatus, which is applied to a terminal, where the terminal is located in a coverage area of a first communication mode network and/or a second communication mode network, as shown in fig. 21, the apparatus includes a processor 31 and a transceiver 32,

the processor 31 is configured to establish a first session with a first communication mode network side device;

the transceiver 32 is configured to obtain indication information of the first communication mode network-side device, where the indication information is used to indicate that the terminal establishes a transport layer path with the second communication mode network-side device before the first session is interrupted;

the processor 31 is further configured to establish a transport layer path with the second communication mode network-side device before the first session is interrupted.

In the embodiment, the network side indicates the terminal to establish a bottom dual-path for the service in advance before the single network session is interrupted, and trigger the establishment of the transmission layer multi-path, so that the service experience without reconnection delay can be provided for the terminal with the IP change but the service is uninterrupted, and the problem of service interruption caused by incapability of maintaining the IP address in a simple and independent core network configuration scene is solved.

Optionally, the transceiver 32 is specifically configured to acquire the indication information in the first session establishment procedure or in the first communication mode network attachment procedure.

Optionally, the transceiver 32 is specifically configured to send a session establishment request to the first communication mode network side device; and receiving a session establishment request response of the first communication mode network side equipment, wherein the session establishment request response carries the indication information.

Optionally, the transceiver 32 is specifically configured to send an attach request to the first communication mode network side device; and receiving an attach request response of the first communication mode network side equipment, wherein the attach request response carries the indication information.

Optionally, the transceiver 32 is further configured to send a session establishment request to the first communication mode network side device, where the session establishment request indicates that a session mode is SSC1; receiving a session establishment rejection request of the first communication mode network side equipment, wherein the session establishment rejection request carries a cause value or a session mode SSC3; and sending a session establishment request again to the first communication mode network side equipment, wherein the session establishment request indicates that the session mode is SSC3.

Optionally, the first session is an SSC3 session.

Optionally, before the transceiver 32 sends the session establishment request to the first communication mode network side device, the processor detects that the signal strength of the first communication mode network is greater than the signal strength of the second communication mode network.

Optionally, the processor 31 is specifically configured to detect signal strengths of the first communication mode network and the second communication mode network; when the signal intensity of the second communication mode network is greater than a first threshold value, establishing a second session with the second communication mode network side equipment, and establishing a transmission layer path between the second communication mode network side equipment and the second communication mode network side equipment; releasing the first session when the signal strength of the first communication mode network is less than a second threshold, the second threshold being less than the first threshold.

Optionally, the processor 31 is specifically configured to establish a new transport sub-stream with the network-side device in the second communication mode when the transport layer supports multipath transmission; and when the transport layer does not support multipath transmission, establishing a new TCP connection between the second communication mode network side equipment and the second communication mode network side equipment.

An embodiment of the present invention further provides a connection establishing apparatus, which is applied to a network-side device in a first communication mode and/or a second communication mode, as shown in fig. 22, where the apparatus includes a processor 41 and a transceiver 42,

the transceiver 42 is configured to send indication information to a terminal in a coverage area, where the indication information is used to instruct the terminal to establish a transport layer path with a second communication mode network-side device before a first session with the first communication mode network-side device is interrupted.

Optionally, the transceiver 42 is specifically configured to send the indication information to the terminal in a session establishment procedure between the terminal and the network side device or in an attach procedure of the terminal.

Optionally, the transceiver 42 is specifically configured to receive a session establishment request of the terminal; and sending a session establishment request response to the terminal, wherein the session establishment request response carries the indication information.

Optionally, the transceiver 42 is specifically configured to receive an attach request of the terminal; and sending an attachment request response to the terminal, wherein the attachment request response carries the indication information.

Optionally, the transceiver 42 is further configured to receive a session establishment request of the terminal, where the session establishment request indicates that the session mode is SSC1; sending a session establishment rejection request to the terminal, wherein the session establishment rejection request carries a cause value or a session mode SSC3; and receiving a session establishment request sent again by the terminal, wherein the session establishment request indicates that the session mode is SSC3.

It is to be understood that the embodiments described herein may be implemented in hardware, software, firmware, middleware, microcode, or a combination thereof. For a hardware implementation, the Processing units may be implemented within one or more Application Specific Integrated Circuits (ASICs), digital Signal Processors (DSPs), digital Signal Processing Devices (DSPDs), programmable Logic Devices (PLDs), field Programmable Gate Arrays (FPGAs), general purpose processors, controllers, micro-controllers, microprocessors, other electronic units configured to perform the functions described herein, or a combination thereof.

For a software implementation, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in a memory and executed by a processor. The memory may be implemented within the processor or external to the processor.

The embodiments in the present specification are all described in a progressive manner, and each embodiment focuses on differences from other embodiments, and portions that are the same and similar between the embodiments may be referred to each other.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, apparatus, or computer program product. Accordingly, embodiments of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, embodiments of the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

Embodiments of the present invention are described with reference to flowchart illustrations and/or block diagrams of methods, user terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing user terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing user terminal device, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing user terminal device to cause a series of operational steps to be performed on the computer or other programmable user terminal device to produce a computer implemented process such that the instructions which execute on the computer or other programmable user terminal device provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present invention have been described, additional variations and modifications of these embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including the preferred embodiment and all changes and modifications that fall within the true scope of the embodiments of the present invention.

It is further noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "include", "including" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or user terminal device including a series of elements includes not only those elements but also other elements not explicitly listed or inherent to such process, method, article, or user terminal device. Without further limitation, an element defined by the phrases "comprising one of \ 8230; \8230;" 8230; "does not exclude the presence of additional like elements in a process, method, article, or user terminal device that comprises the element.

While the foregoing is directed to the preferred embodiment of the present invention, it will be appreciated by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A connection establishment method applied to a terminal, wherein the terminal is located in a coverage area of a first communication mode network and/or a second communication mode network, the method comprising:

before the first session is interrupted, establishing a transmission layer path between the first session and the network side equipment in the second communication mode;

before the first session is established with the first communication mode network side device, the method further comprises:

2. The connection establishing method according to claim 1, wherein the indication information indicates that the first communication mode network and the second communication mode network are independently networked and do not interface with each other.

3. The method according to claim 1, wherein the obtaining the indication information of the first communication mode network side device comprises:

4. The connection establishing method according to claim 3, wherein the establishing a first session with the first communication mode network side device, and the obtaining the indication information in the first session establishing process comprises:

5. The method according to claim 3, wherein acquiring the indication information during the attaching of the first communication mode network comprises:

6. The connection establishment method of claim 1, wherein the first session is an SSC3 session.

7. The connection establishing method according to claim 4, wherein before sending the session establishment request to the first communication mode network side device, the method further comprises:

8. The connection establishing method according to claim 1, wherein establishing a transport layer path with a second communication mode network side device before the first session is interrupted comprises:

9. The method according to claim 1, wherein the establishing the transport layer path with the second communication mode network side device comprises:

10. A connection establishment method is applied to a network side device in a first communication mode and/or a second communication mode, and comprises the following steps:

sending indication information to a terminal in a coverage range, wherein the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and a second communication mode network side device before a first session between the terminal and the first communication mode network side device is interrupted;

the method further comprises the following steps:

11. The connection establishing method according to claim 10, wherein the sending the indication information to the terminals within the coverage area comprises:

12. The connection establishing method according to claim 11, wherein sending the indication information to the terminal in a session establishment procedure between the terminal and the network-side device comprises:

receiving a session establishment request of the terminal;

13. The connection establishing method according to claim 11, wherein sending the indication information to the terminal during the terminal's attach procedure comprises:

receiving an attachment request of the terminal;

14. A connection set-up device for a terminal, the terminal being located within the coverage of a first communication mode network and/or a second communication mode network, the device comprising a processor and a transceiver,

the processor is further configured to establish a transport layer path with a second communication mode network side device before the first session is interrupted;

the transceiver is further configured to send a session establishment request to the first communication mode network side device, where the session establishment request indicates that a session mode is SSC1; receiving a session establishment rejection request of the first communication mode network side equipment, wherein the session establishment rejection request carries a cause value or a session mode SSC3; and sending a session establishment request again to the first communication mode network side equipment, wherein the session establishment request indicates that the session mode is SSC3.

15. A connection establishment apparatus, characterized in that, a network side device applied to a first communication mode and/or a second communication mode, the apparatus comprises a processor and a transceiver,

the transceiver is used for sending indication information to a terminal in a coverage range, and the indication information is used for indicating the terminal to establish a transmission layer path between the terminal and a second communication mode network side device before a first session between the terminal and the first communication mode network side device is interrupted;

the transceiver is further configured to receive a session establishment request of the terminal, where the session establishment request indicates that a session mode is SSC1; sending a session establishment rejection request to the terminal, wherein the session establishment rejection request carries a cause value or a session mode SSC3; and receiving a session establishment request sent again by the terminal, wherein the session establishment request indicates that the session mode is SSC3.

16. A communication device, comprising: memory, processor and computer program stored on the memory and executable on the processor, which computer program, when executed by the processor, carries out the steps in the connection establishment method according to any one of claims 1 to 13.

17. A computer-readable storage medium, having stored thereon a computer program which, when being executed by a processor, carries out the steps of a method for establishing a connection as claimed in any one of claims 1 to 13.