Patent Description:
As the use of mobile devices becomes more widespread and as network service applications (e.g. video streams, virtual reality, autonomous vehicles, and so on) have progressed, the requirements on data traffic have increased. Therefore, Multi-Access Edge Computing (MEC) is used in <NUM> communication for the increasing data traffic requirements and computations. The MEC is used to provide cloud computation capability and an Information Technology (IT) environment to the edge of the mobile network. Its main purpose is to reduce the computation performed by the core network apparatus and assist operators in establishing a specific mobile experience platform for the customers.

However, in the structure of <NUM> MEC, when the User Plane Function (UPF) needs to be switched (e.g. a handover is taking place on the user equipment (UE)), the service of the UE may be interrupted because of the UPF switch. As a result, the user experience will suffer.

<CIT> discloses a network triggered service request method performed by an access and mobility management function device. <CIT> discloses a method and an apparatus for supporting migration of mobile edge computing in a wireless communication system.

Other aspects and features of the disclosure will become apparent to those with ordinary skill in the art upon review of the following descriptions of specific embodiments of MEC system, MEC device, UE and UPF switch method.

The disclosure will become more fully understood by referring to the following detailed description with reference to the accompanying drawings, wherein:.

The following description is of the best-contemplated mode of carrying out the disclosure. This description is made for the purpose of illustrating the general principles of the disclosure and should not be taken in a limiting sense. The scope of the disclosure is best determined by reference to the appended claims.

<FIG> is a block diagram of a Multi-Access Edge Computing (MEC) system <NUM> according to an embodiment of the disclosure. As shown in <FIG>, the MEC system <NUM> may comprise user equipment (UE) <NUM>, a first access network <NUM>, a second access network <NUM>, an MEC device <NUM> and a core network <NUM>. It should be noted that <FIG> presents a simplified block diagram in which only the elements relevant to the disclosure are shown. However, the disclosure should not be limited to what is shown in <FIG>.

According to an embodiment of the disclosure, the UE <NUM> may be a smart phone, personal data assistant (PDA), a paging device, a note book, a desktop computer, a wireless portable device or any computing device with wireless communication interface.

According to an embodiment of the disclosure, the first access network <NUM> may be a non-3GPP access network, e.g. a Wi-Fi access point (AP), but the disclosure should not be limited thereto. In addition, according to an embodiment of the disclosure, the second access network <NUM> may be a 3GPP access network, e.g. base station (e.g. gNB), but the disclosure should not be limited thereto.

<FIG> is a block diagram of the MEC device <NUM> and the core network <NUM> according to an embodiment of the disclosure. As shown in <FIG>, the MEC device may comprise a relay User Plane Function (UPF) module <NUM>, a UPF module <NUM>, a non-3GPP Inter-Working Function (N3IWF) module <NUM>, a control circuit <NUM>, an Application Function (AF) module <NUM> and an Access Network Service module <NUM>. It should be noted that <FIG> presents a simplified block diagram in which only the elements relevant to the disclosure are shown. However, the disclosure should not be limited to what is shown in <FIG>. The MEC device <NUM> also can comprise other elements and function modules. In addition, there is only one UPF module <NUM> in <FIG>, but the disclosure should not be limited thereto. The MEC device <NUM> also can establish a plurality of UPF modules. Each UPF module may serve one or more UE. Furthermore, the "UPF" in the disclosure can be regarded as an intermediate UPF (I-UPF).

In addition, as shown in <FIG>, the core network <NUM> may comprise an Access and Mobility Function (AMF) module <NUM>, a Session Management Function (SMF) module <NUM> and a Network Exposure Function (NEF) module <NUM>. It should be noted that <FIG> presents a simplified block diagram in which only the elements relevant to the disclosure are shown. However, the disclosure should not be limited to what is shown in <FIG>. The core network <NUM> also can comprise other elements and function modules. According to the embodiments of the disclosure, the AMF module <NUM> may manage the register and authentication operations of the UE <NUM>. The SMF module <NUM> may manage the sessions of the UE <NUM> and control the configurations and establishments of the UPF modules. The SMF module <NUM> may communicate with relay UPF module <NUM> and the UPF module <NUM> through a N4 interface. The NEF module <NUM> may communicate with the AF module <NUM> through a N33 interface.

According to an embodiment of the disclosure, when the UE <NUM> attaches to the network through the first access network <NUM> or the second access network <NUM>, the AF module <NUM> may notify the NEF module <NUM> to establish an idle session between the UE <NUM> and the relay UPF module <NUM>.

In addition, when the UE <NUM> attaches to the network through the first access network <NUM> or the second access network <NUM>, the UE <NUM> may use the UPF module <NUM> to perform data transmission with the network end and obtain the service (the application corresponding to the Access Network Service module <NUM>) from the network end. According to an embodiment of the disclosure, when the UE <NUM> communicates with the core network <NUM> through a 3GPP access network (e.g. the second access network <NUM>), the core network <NUM> can directly communicate with the UE <NUM> through the UPF module <NUM>. According to another embodiment of the disclosure, when the UE <NUM> communicates with the core network <NUM> through a non-3GPP access network (e.g. the first access network <NUM>), the UE <NUM> needs to communicate with the core network <NUM> through the N3IWF module <NUM>. It should be noted that there is only one UPF module <NUM> in <FIG>, but the disclosure should not be limited thereto. The first access network <NUM> or the second access network <NUM> may respectively correspond to different UPF modules.

According to an embodiment of the disclosure, the control circuit <NUM> may determine whether a trigger condition is generated. According to an embodiment of the disclosure, the trigger condition may comprise whether a handover needs to be performed on UE <NUM>, whether to update the UPF, whether to allocate the UPF resource, and whether a slicing policy is triggered, but the disclosure should not be limited thereto.

According to an embodiment of the disclosure, when the control circuit <NUM> determines that a trigger condition is generated (e.g. handover needs to be performed on UE <NUM>), the control circuit <NUM> may notify the AF module <NUM> that the trigger condition is generated. After the AF module <NUM> receives the notification, according to the notification, the AF module <NUM> may determine whether the service for the UE <NUM> needs to be switched from the UPF module <NUM> to a new UPF module.

When the AF module <NUM> determines that the service for the UE <NUM> needs to be switched from the UPF module <NUM> to a new UPF module, the AF module <NUM> may determine whether the new UPF is activated (or the new UPF module has existed). According to an embodiment of the disclosure, if the new UPF has been activated, the AF module <NUM> may send notification to the NEF module <NUM> of the core network <NUM> to indicate the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the new UPF module.

According to an embodiment of the disclosure, if the new UPF has not been activated, the AF module <NUM> may send notification to the NEF module <NUM> of the core network <NUM> to indicate the SMF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the relay UPF module <NUM> first, and the AF module <NUM> may continuously monitor whether the new UPF is activated. When the SMF module <NUM> of the core network <NUM> has established the new UPF module in the MEC device <NUM>, the AF module <NUM> may send notification to the NEF module <NUM> of the core network <NUM> to indicate the SMF module <NUM> to switch the service for the UE <NUM> from the relay UPF module <NUM> to the new UPF module.

According to an embodiment of the disclosure, if the new UPF module corresponds to a non-3GPP access network (e.g. the first access network <NUM>), the AF module <NUM> may send a notification to the NEF module <NUM> to indicate the SMF module <NUM> to perform authentication and encryption through the N3IWF module <NUM> to the UE <NUM> and the new UPF before switching the service for the UE <NUM> from the UPF module <NUM> to the new UPF module.

In addition, according to an embodiment of the disclosure, if the new UPF module corresponds to a non-3GPP access network (e.g. the first access network <NUM>), before the AF module <NUM> may send a notification to the NEF module <NUM> to indicate the SMF module <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the new UPF module, the AF module <NUM> may determine whether the UE <NUM> has detached from the N3IWF module <NUM> first. When the UE <NUM> has detached from the N3IWF module <NUM>, the AF module <NUM> may send a notification to the NEF module <NUM> to indicate the SMF module <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the new UPF module.

According to an embodiment of the disclosure, when the service for the UE <NUM> from a first UPF module <NUM> to a second UPF module and the second UPF module has not been activated, the receiving device (not shown in figures) of the UE <NUM> may receive a first indication from the core network <NUM>, and the processing device (not shown in figures) of the UE <NUM> may switch the service for the UE <NUM> to a relay UPF module first based on the first indication. After the second UPF module has been activated, the receiving device of the UE <NUM> may receive a second indication from the core network <NUM>, the processing device of the UE <NUM> may switch the service for the UE <NUM> to the second UPF module first based on the second indication.

<FIG> is a flow chart illustrating a UPF switch method according to an embodiment of the disclosure. The UPF switch method can be applied to the MEC system <NUM>. In addition, the embodiment is based on the condition of the UE <NUM> handing over from the second access network <NUM> to the first access network <NUM> (i.e. hand over form the 3GPP access network to the non-3GPP access network). In step S310, when the UE <NUM> attaches to the network, the AF module <NUM> may notify the NEF module <NUM> to establish an idle session between the UE <NUM> and the relay UPF module <NUM>. In step S320, the control circuit <NUM> may determine whether a trigger condition is generated. If the trigger condition is not generated, the control circuit <NUM> may perform step S320 continuously.

When the control circuit <NUM> determines that the UE <NUM> needs to hand over from the second access network <NUM> to the first access network <NUM> (i.e. the trigger condition is generated), step S330 is performed. In step S330, the control circuit <NUM> may notify the AF module <NUM> that the handover of the UE <NUM> will be performed. In step S340, the AF module <NUM> may determine whether the service for the UE <NUM> needs to be switched from the current UPF module (i.e. UPF module <NUM>) to a new UPF module (not shown in figures). If the service for the UE <NUM> does not need to be switched from the UPF module <NUM> to a new UPF module, the method backs to step S320. If the service for the UE <NUM> needs to be switched from the UPF module <NUM> to a new UPF module, step S350 is performed. In step S350, the AF module <NUM> may determine whether the new UPF module has been activated (or determine whether the new UPF exists).

If the new UPF module has been activated, step S360 is performed. In step S360, the AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the new UPF module. If the new UPF module has not been activated, step S370 is performed. In step S370, the AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the relay UPF module <NUM> first. In step S380, the AF module <NUM> may monitor (or determine) whether the new UPF module has been activated continuously. If the new UPF module has not been activated, the AF module <NUM> may perform step S380 continuously.

When the SMF module <NUM> of the core network <NUM> has established the new UPF module in the MEC device <NUM>, step S390 is performed. In step S390, the AF module <NUM> may determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>. Specifically, in step S390, the SMF module <NUM> may determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM> first and then transmit the determination result to the NEF module <NUM>. Then, the NEF module <NUM> may transmit the determination result generated by the SMF module <NUM> to the AF module <NUM>. Accordingly, the AF module <NUM> will be able to determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>. If the UE <NUM> and the new UPF module have not been authorized and encrypted through the N3IWF module <NUM>, the AF module <NUM> may perform step S390 continuously. When the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>, step S360 is performed. The AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> to the new UPF module.

It should be noted that in the condition of the condition of the UE <NUM> handing over from the second access network <NUM> to another 3GPP access network (i.e. hand over form the 3GPP access network to another 3GPP access network), step S390 does not need to be performed. That is to say, in this condition, when the SMF module <NUM> of the core network <NUM> has established the new UPF module in the MEC device <NUM>, the AF module <NUM> may directly notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> to the new UPF module.

<FIG> is a flow chart illustrating a UPF switch method according to another embodiment of the disclosure. The UPF switch method can be applied to the MEC system <NUM>. In addition, the embodiment is based on the condition of the UE <NUM> handing over from the first access network <NUM> to the second access network <NUM> (i.e. hand over form the non-3GPP access network to the 3GPP access network). In step S410, when the UE <NUM> attaches to the network, the AF module <NUM> may notify the NEF module <NUM> to establish an idle session between the UE <NUM> and the relay UPF module <NUM>. In step S420, the control circuit <NUM> may determine whether a trigger condition is generated. If the trigger condition is not generated, the control circuit <NUM> may perform step S420 continuously.

When the control circuit <NUM> determines that the UE <NUM> needs to hand over from the first access network <NUM> to the second access network <NUM> (i.e. the trigger condition is generated), step S430 is performed. In step S430, the control circuit <NUM> may notify the AF module <NUM> that the handover of the UE <NUM> will be performed. In step S440, the AF module <NUM> may determine whether the service for the UE <NUM> needs to be switched from the UPF module <NUM> to a new UPF module (not shown in figures). If the service for the UE <NUM> does not need to be switched from the UPF module <NUM> to a new UPF module, the method backs to step S420. If the service for the UE <NUM> needs to be switched from the UPF module <NUM> to a new UPF module, step S350 is performed. In step S450, the AF module <NUM> may determine whether the new UPF module has been activated (or determine whether the new UPF exists).

If the new UPF module has been activated, step S460 is performed. In step S460, the AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the new UPF module. If the new UPF module has not been activated, step S470 is performed. In step S470, the AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the relay UPF module <NUM> first. In step S480, the AF module <NUM> may monitor whether the new UPF module has been activated continuously. If the new UPF module has not been activated, the AF module <NUM> may perform step S480 continuously.

When the SMF module <NUM> of the core network <NUM> has established the new UPF module in the MEC device <NUM>, step S490 is performed. In step S490, the AF module <NUM> may determine whether the UE <NUM> has detached from the N3IWF module <NUM>. Specifically, in step S490, the SMF module <NUM> may determine whether the UE <NUM> has detached from the N3IWF module <NUM> first and then transmit the determination result to the NEF module <NUM>. Then, the NEF module <NUM> may transmit the determination result generated by the SMF module <NUM> to the AF module <NUM>. Accordingly, the AF module <NUM> will be able to determine whether the UE <NUM> has detached from the N3IWF module <NUM>. If the UE <NUM> has not detached from the N3IWF module <NUM>, the AF module <NUM> may perform step S490 continuously. If the UE <NUM> has detached from the N3IWF module <NUM>, step S460 is performed. The AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> to the new UPF module.

It should be noted that in the condition of the UE <NUM> handing over from the first access network <NUM> to another non-3GPP access network <NUM> (i.e. hand over form the non-3GPP access network to another non-3GPP access network), step S390 needs to be performed between step S480 and step S490. That is to say, after the SMF module <NUM> of the core network <NUM> has established the new UPF module in the MEC device <NUM>, the AF module <NUM> may determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM> first. Specifically, the SMF module <NUM> may determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM> first and then transmit the determination result to the NEF module <NUM>. Then, the NEF module <NUM> may transmit the determination result generated by the SMF module <NUM> to the AF module <NUM>. Accordingly, the AF module <NUM> will be able to determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>. Until the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>, step S490 is not performed.

<FIG> is a flow chart illustrating a UPF switch method according to another embodiment of the disclosure. The UPF switch method can be applied to the MEC system <NUM>. In addition, the embodiment is based on the condition of the UE <NUM> having a low priority. In step S510, when the UE <NUM> attaches to the network, the AF module <NUM> may notify the NEF module <NUM> to establish an idle session between the UE <NUM> and the relay UPF module <NUM>. In step S520, the control circuit <NUM> may determine whether a trigger condition is generated. If the trigger condition is not generated, the control circuit <NUM> may perform step S520 continuously.

When the control circuit <NUM> determines that the resource of the UPF module <NUM> corresponding to the slice of the UE (not shown in figures) with high priority (i.e. the trigger condition is generated) is not enough, step S530 is performed. In step S530, the control circuit <NUM> may notify the AF module <NUM> that the UE <NUM> with low priority needs to be removed from the current UPF module (i.e. UPF module <NUM>). In step S540, the AF module <NUM> may determine whether a new UPF module has been activated (or determine whether a new UPF exists).

If the new UPF module has been activated, step S550 is performed. In step S550, the AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the new UPF module. If the new UPF module has not been activated, step S560 is performed. In step S560, the AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> from the UPF module <NUM> to the relay UPF module <NUM> first. In step S570, the AF module <NUM> may monitor whether the new UPF module has been activated continuously. If the new UPF module has not been activated, the AF module <NUM> may perform step S570 continuously.

When the SMF module <NUM> of the core network <NUM> has established the new UPF module in the MEC device <NUM>, step S580 is performed. In step S580, the AF module <NUM> may determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>. Specifically, in step S580, the SMF module <NUM> may determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM> first and then transmit the determination result to the NEF module <NUM>. Then, the NEF module <NUM> may transmit the determination result generated by the SMF module <NUM> to the AF module <NUM>. Accordingly, the AF module <NUM> will be able to determine whether the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>. If the UE <NUM> and the new UPF module have not been authorized and encrypted through the N3IWF module <NUM>, the AF module <NUM> may perform step S580 continuously. When the UE <NUM> and the new UPF module have been authorized and encrypted through the N3IWF module <NUM>, step S550 is performed. The AF module <NUM> may notify the NEF module <NUM> of the core network <NUM> to switch the service for the UE <NUM> to the new UPF module.

The steps of the UPF switch method associated with updating UPF or allocating resources are similar to the steps illustrated in <FIG>. Therefore, details will not repeat again.

<FIG> is a flow chart illustrating a UPF switch method according to an embodiment of the disclosure. The UPF switch method can be applied to the MEC system <NUM>. As shown in <FIG>, in step S610, when a UE of the MEC system <NUM> attaches to a network, an MEC device of the MEC system <NUM> may establish an idle session between the UE and a relay UPF module.

In step S620, when the MEC device of the MEC system <NUM> determines that the service for the UE needs to be switched from a first UPF module and a second UPF module, and the second UPF module has not been activated, the MEC device of the MEC system <NUM> indicate a core network of the MEC system <NUM> to switch the service for the UE from the first UP to the relay UPF first.

In the UPF switch method, the MEC device of the MEC system <NUM> may determine whether the second UPF has been activated. When the MEC device of the MEC system <NUM> determines that the second UPF has been activated, the MEC device may indicate the core network of the MEC system <NUM> to switch the service for the UE from the first UPF module to the second UPF module.

According to the UPF switch methods provided in the disclosure, when the service for the UE needs to be switched from a UPF module to another UPF module, the MEC device can determine whether to switch the service for the UE to a relay UPF module first. Therefore, in the UPF switch methods provided in the disclosure, the interruption of the service for the UE can be avoided when the service for the UE needs to be switched from a UPF module to another UPF module.

Use of ordinal terms such as "first", "second", "third", etc., in the disclosure and claims is for description. It does not by itself connote any order or relationship.

The steps of the method described in connection with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module (e.g., including executable instructions and related data) and other data may reside in a data memory such as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of computer-readable storage medium known in the art. A sample storage medium may be coupled to a machine such as, for example, a computer/processor (which may be referred to herein, for convenience, as a "processor") such that the processor can read information (e.g., code) from and write information to the storage medium. A sample storage medium may be integral to the processor. The ASIC may reside in user equipment. Alternatively, the processor and the storage medium may reside as discrete components in user equipment. Moreover, in some aspects any suitable computer-program product may comprise a computer-readable medium comprising codes relating to one or more of the aspects of the disclosure. In some aspects a computer program product may comprise packaging materials.

The above paragraphs describe many aspects. Obviously, the teaching of the disclosure can be accomplished by many methods, and any specific configurations or functions in the disclosed embodiments only present a representative condition. Those who are skilled in this technology will understand that all of the disclosed aspects in the disclosure can be applied independently or be incorporated.

Claim 1:
A Multi-Access Edge Computing, MEC, system (<NUM>), comprising:
a user equipment (<NUM>), UE;
an MEC device (<NUM>), comprising a relay User Plane Function, UPF, module (<NUM>), a first UPF module (<NUM>), and a second UPF module; and
a core network (<NUM>), configured to perform a UPF path management corresponding to the UE (<NUM>) based on a notification from the MEC device (<NUM>),
wherein when the UE (<NUM>) attaches to a network, the MEC device (<NUM>) is configured to establish an idle session between the UE (<NUM>) and the relay UPF module (<NUM>),
wherein when the MEC device (<NUM>) determines that a service for the UE (<NUM>) needs to be switched from the first UPF module (<NUM>) to the second UPF module and the second UPF module has not been activated, the MEC device (<NUM>) is configured to notify the core network (<NUM>) to switch the service for the UE (<NUM>) from the first UPF module (<NUM>) to the relay UPF module (<NUM>) first.