CN117981396A - Improvements in and relating to multiple USIMs in a mobile telecommunications environment - Google Patents

Abstract

A method and apparatus having Multiple Universal Subscriber Identity Module (MUSIM) capabilities in a wireless communication system. In case the User Equipment (UE) does not have allowed Network Slice Selection Assistance Information (NSSAI) and the associated trigger is related to the MUSIM feature, a service request procedure is initiated.

Description

Improvements in and relating to multiple USIMs in a mobile telecommunications environment

Technical Field

The present disclosure relates generally to Universal Mobile Telecommunications Service (UMTS) Subscriber Identity Module (SIM) within a User Equipment (UE) that serves as an identifier for the UE, and more particularly to improvements in and relating to multiple Universal Subscriber Identity Modules (USIMs) in a mobile telecommunications environment.

Background

The fifth generation (5G) mobile communication technology defines a wide frequency band that enables high transmission rates and new services, not only in the "Sub 6GHz" frequency band such as 3.5GHz, but also in the "Above 6GHz" frequency band called millimeter waves including 28GHz and 39 GHz. In addition, it is also considered to implement a sixth generation (6G) mobile communication technology (referred to as super 5G system) in a terahertz frequency band (e.g., 95GHz to 3THz frequency band) to achieve a transmission rate 50 times faster than that of the 5G mobile communication technology and an ultra-low delay of one tenth of that of the 5G mobile communication technology.

In the development of 5G mobile communication technologies, in order to support services and meet performance requirements of enhanced mobile broadband (eMBB), ultra-reliable low-delay communication (URLLC), and large-scale machine type communication (mMTC), there has been continuous standardization, with respect to beam forming and large-scale multiple input-multiple output (MIMO) for alleviating radio wave path loss in millimeter waves and increasing radio wave transmission distances, support of dynamic operation of a parameter set (e.g., operating a plurality of subcarrier intervals) and a slot format for effectively utilizing millimeter wave resources, initial access technologies for supporting multi-beam transmission and broadband, definition and operation of a bandwidth part (BWP), new channel coding methods such as Low Density Parity Check (LDPC) codes for mass data transmission and polarity codes for high reliability transmission of control information, L2 pre-processing, and network slicing for providing a dedicated network for a specific service.

Currently, in view of services that the 5G mobile communication technology will support, improvements and performance enhancements of the initial 5G mobile communication technology are also being discussed, and there has been a physical layer standardization for technologies such as vehicle-to-everything (V2X), V2X for assisting driving determination of an autonomous vehicle based on information sent by the vehicle about the position and status of the vehicle and for enhancing user convenience, new radio unlicensed (NR-U) aimed at system operation meeting various regulatory-related requirements in unlicensed bands, radio (NR) UE power saving, non-terrestrial network (NTN), which is UE-satellite direct communication for providing coverage in areas where communication with terrestrial networks is unavailable, and positioning.

Furthermore, air interface architectures/protocols with respect to technologies such as the industrial internet of things (IIoT) are constantly standardized to support new services through interworking and convergence with other industries, integrated Access and Backhaul (IAB) to provide mobility enhancements for network service area extensions, including conditional handoffs and Dual Active Protocol Stack (DAPS) handoffs, by supporting wireless backhaul links and access links in an integrated manner, and two-step random access (2-step Random Access Channel (RACH) for NR) to simplify the random access procedure. In terms of system architecture/services, standardization of 5G baseline architecture (e.g., service-based architecture or service-based interface) is also ongoing for combining Network Function Virtualization (NFV) and Software Defined Network (SDN) technologies, as well as Mobile Edge Computing (MEC) for receiving services based on UE location.

With commercialization of the 5G mobile communication system, more and more connection devices will be connected to the communication network, and it is expected that functions and performances of the 5G mobile communication system and integrated operations of the connection devices will be necessary. For this reason, new researches related to augmented reality (XR) are being planned for effectively supporting Augmented Reality (AR), virtual Reality (VR), mixed Reality (MR), etc., improving 5G performance and reducing complexity by using Artificial Intelligence (AI) and Machine Learning (ML), AI service support, metauniverse service support, and unmanned aerial vehicle communication.

Furthermore, such development of the 5G mobile communication system will not only be the basis for developing new waveforms for providing terahertz band coverage of the 6G mobile communication technology, multi-antenna transmission technologies such as full-size MIMO (FD-MIMO), array antennas and large-scale antennas, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM) and Reconfigurable Intelligent Surface (RIS) based on lenses of metamaterial and antennas for improving coverage of terahertz band signals, but also the basis for developing full duplex technology for improving frequency efficiency of the 6G mobile communication technology and improving system network, AI-based communication technology, system optimization is achieved from the design stage using satellites and AI, and end-to-end AI support functions are internalized, and next generation distributed computing technology for achieving services at a complexity level exceeding the UE operation capability limit by using ultra-high performance communication and computing resources.

Disclosure of Invention

Technical proposal

According to one aspect, a method of operating a UE having Multiple Universal Subscriber Identity Module (MUSIM) capabilities in a wireless communication system is provided. In the event that the UE does not have allowed Network Slice Selection Assistance Information (NSSAI) and the associated trigger is related to the MUSIM feature, a service request procedure is initiated.

According to another aspect, a UE having MUSIM capabilities in a wireless communication system is provided. The UE includes a transceiver and at least one processor coupled with the transceiver. In the event that the UE does not have admission NSSAI and the associated trigger is related to the MUSIM feature, a service request procedure is initiated.

Drawings

The above and other aspects, features and advantages of the present disclosure will become more apparent when the following detailed description is taken in conjunction with the accompanying drawings in which:

FIG. 1 is a flow diagram illustrating abnormal UE behavior for a service request procedure due to MUSIM features, according to an embodiment;

fig. 2 is a flowchart showing how a UE may obtain MUSIM services in a fifth generation mobility management (5 GMM) -CONNECTED mode with Radio Resource Control (RRC) inactivity indication, according to an embodiment;

Fig. 3 is a flowchart showing how a UE obtains MUSIM services in 5GMM-IDLE/EMM-IDLE mode with a suspend indication according to an embodiment;

Fig. 4 is a diagram illustrating a structure of a UE according to an embodiment; and

Fig. 5 is a diagram showing the structure of a base station according to an embodiment.

Detailed Description

Embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Although the same or similar elements are shown in different drawings, they may be denoted by the same or similar reference numerals. Detailed descriptions of constructions or processes known in the art may be omitted to avoid obscuring the subject matter of the present disclosure.

It may be advantageous to set forth definitions of certain words and phrases used herein. The term "couple" and its derivatives refer to any direct or indirect communication between two or more elements, whether or not those elements are in physical contact with one another. The terms "transmit," "receive," and "communicate," and derivatives thereof, include both direct and indirect communication. The terms "include" and "comprise" and derivatives thereof mean inclusion without limitation. The term "or" is inclusive, meaning and/or. The phrase "associated with" and derivatives thereof is intended to include, be included in, be connected to, be interconnected with, be included in, be connected to or be connected with, be coupled to or be coupled with, be in communication with, cooperate with, be interlaced with, be juxtaposed with, be in proximity to, be bound to or be bound with, have the property of having the right. The term "controller" means any device, system, or portion thereof that controls at least one operation. Such a controller may be implemented in hardware or firmware, as well as a combination of software and/or firmware. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. When used with a list of items, the phrase "at least one" means that different combinations of one or more of the listed items can be used, and that only one item in the list may be required. For example, "at least one of a, B, and C" includes any combination of: a, B, C, a and B, a and C, B and C, and a and B and C. For example, "at least one of a, B, or C" includes any combination of: a, B, C, a and B, a and C, B and C, and a and B and C.

Furthermore, the various functions described below may be implemented or supported by one or more computer programs, each of which is formed from computer readable program code and embodied in a computer readable medium. The terms "application" and "program" refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, related data, or a portion thereof adapted for implementation in a suitable computer readable program code. The phrase "computer readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer readable medium" includes any type of medium capable of being accessed by a computer, such as Read Only Memory (ROM), random Access Memory (RAM), a hard disk drive, a Compact Disc (CD), a Digital Video Disc (DVD), or any other type of memory. "non-transitory" computer-readable media do not include wired, wireless, optical, or other communication links that transmit transitory electrical signals or other signals. Non-transitory computer readable media include media that can permanently store data and media that can store and later overwrite data, such as rewritable optical disks or erasable memory devices.

The terminology used herein is not intended to limit and/or define the scope of the disclosure. For example, unless defined otherwise, technical or scientific terms used in this disclosure should have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs.

It should be appreciated that the terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are merely used to distinguish one element from another. Similar words, such as "a" and "an" or "the" in the singular do not mean a limitation in number but rather that there is at least one unless the context clearly indicates otherwise.

As used herein, any reference to "one example" or "an example," "one embodiment," or "an embodiment" means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase "in one embodiment" or "in one example" in various places in the specification are not necessarily all referring to the same embodiment.

It will be further understood that like terms, such as the terms "comprises" or "comprising," mean that elements or objects that appear before the term include the listed elements or objects that appear after the term and their equivalents, but do not exclude other elements or objects. Similar terms, such as "connected" or "connected," are not limited to physical or mechanical connections, but may also include direct or indirect electrical connections. "upper", "lower", "left" and "right" are used merely to indicate relative positional relationships, which may change accordingly when the absolute position of the object being described changes.

The examples of the present disclosure are for illustration only and should not be construed as limiting the scope of the present disclosure in any way. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged wireless communication system. For example, although the present disclosure is directed to Long Term Evolution (LTE) and 5G communication systems, those skilled in the art will appreciate that the gist of the present disclosure may be applied to other communication systems having similar technical contexts and channel formats, with minor modifications, without departing from the scope of the present disclosure. For example, the communication system may include a global system for mobile communications (GSM) system, a Code Division Multiple Access (CDMA) system, a Wideband Code Division Multiple Access (WCDMA) system, a General Packet Radio Service (GPRS), an LTE system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD), a Universal Mobile Telecommunications System (UMTS), a Worldwide Interoperability for Microwave Access (WiMAX) communication system, a 5G system, or NR, etc. In addition, the technical scheme of the embodiment can be applied to future-oriented communication technology.

MUSIM UE support more than one USIM and thus can be registered simultaneously with multiple Public Land Mobile Networks (PLMNs) (or more conveniently with the network). In this case, the multiple registrations may cause the UE to switch between PLMNs in order to receive a particular service (e.g., a voice service). The UE may send some information to the serving network (e.g., access and mobility management function (AMF) of the network), which helps determine the UE's preferences with respect to MUSIM operations. For example, the UE may send a "paging restriction" to inform the network whether the UE prefers to be paged, or whether the paging should be restricted for all or part of the services, and so on.

A description of the functionality of MUSIM is provided in 3GPP TR 23.501V17.1.1.

5.38 Support for multiple USIM UEs

5.38.1 Overview

The network and UE may support one or more of the following enhancements to multi-USIM UE operation:

-connection release of clause 5.38.2;

-paging cause indication for voice service as described in clause 5.38.3;

-rejecting the paging request as described in clause 5.38.4;

Paging restrictions as described in clause 5.38.5.

In the registration process (as described in clause 4.2.2.2.2), when the multiple USIM UE has multiple active USIMs, supports and intends to use one or more multiple USIM specific features, it indicates to the AMF that the corresponding multiple USIM function is supported. Based on the indication of supported multiple USIM functionality received from the UE, the AMF should indicate support for multiple USIM features to the UE based on the multiple USIM features supported by the network and any preference policies of the network (if available). When the UE transitions from a multi-USIM UE that previously indicated to the network a USIM for a multi-USIM feature with support to a USIM with only one active, the UE should indicate to the network that all multi-USIM features for the USIM are not supported. The AMF should indicate support for a paging restriction function, and support for a connection release function or a reject paging function.

At most MUSIM UE includes support for various functions of connection release, paging cause indication for voice services, denial of paging request and paging restriction specified in clause 5.4.4a.

The multi USIM UE should use separate PEI for each USIM when registering to the network.

■ 5.38.2 Connection release

If the UE and the network both indicate that each other supports this feature, the multi-USIM UE may request the network to release the UE from the RRC-CONNECTED state of the USIM due to activity on the other USIM.

The UE indicates that its request is released from the RRC-CONNECTED state by initiating a service request procedure or a registration procedure (in case the UE needs to perform a registration update with the network at the same time), including a release indication. If supported, the UE may also provide paging restriction information only with the release indication, as described in clause 5.38.5, which requests network restriction paging. Paging restriction information from the UE is stored in the UE context in the AMF. If no paging restriction information is provided in the service request or the registration request, any stored paging restriction information in the UE context is removed.

When the UE initiates a service request procedure or a registration procedure without providing a release indication, the network removes any stored paging restriction information.

■ And (3) injection: when there is no support for PLMN range for the connection release feature, it may occur that the network does not release the UE when using the connection release request for mobile update. When the UE detects that the network does not support features in the new RA, the UE behavior is not within the scope of this specification.

■ The editor annotates: if connection release is performed through the AS procedure, NR is connected to 5GC, then FFS.

■ Paging cause indication for 5.38.3 voice services

The UE and the network may support paging cause indication for voice service features.

Only when the UE indicates to the network a paging cause indication supporting the voice service feature, the network supporting the paging cause indication of the voice service feature should provide a voice service indication of the IMS voice service in a paging message. As specified in clause 5.4.3.2, the network determines the IMS voice service based on the paging policy indicator.

After receiving the voice service indication in the NGAP paging message from the AMF, the NG-RAN supporting the paging cause indication of the voice service should include the voice service indication in the Uu paging message to the UE.

When the UE context indication supports paging cause indication for voice service feature, the AMF provides an indication to the NG-RAN indicating that paging cause indication for voice service feature is supported in order to require the NG RAN to deliver voice service indication in RAN paging for UE in RRC inactive state. Upon receiving the indication, the NG-RAN supporting the paging cause indication of the voice service indication feature stores it in the UE context. For a UE in RRC inactivity, the NG-RAN should provide a voice service indication in the RAN paging message only if there is a paging cause indication for the voice service indication in the UE context and it detects that the downlink data triggering the RAN paging message is related to voice service based on the paging policy indicator in the header of the received downlink data, as described in clause 5.4.3.2.

A UE supporting paging cause indication of voice service features can distinguish between pages from networks not supporting paging cause indication of voice service features and pages without voice service indication.

■ The editor annotates: how the UE distinguishes pages from networks that do not support the paging cause indication of the voice service feature and pages that do not have the voice service indication depend on the decision of the RAN.

■ 5.38.4 Refusing paging request

If the UE and the network both indicate that each other supports this feature, the multiple USIM UE may establish a connection to respond to a page with a reject page indication to the network, indicate that the UE does not accept the page, and request to return to the CM-IDLE state after sending the response.

When paged by a network, a multi-USIM UE in CM-IDLE state attempts to send a service request message to the network including a reject page indication unless it cannot do so, e.g., due to UE implementation constraints. In addition to rejecting the page indication, if supported by the UE, the UE may include page restriction information in the service request message as described in clause 5.38.5.

■ 5.38.5 Paging restriction

The UE and the network may support paging restriction. If the AMF indicates that the network supports the paging restriction feature, the UE may indicate paging restriction information in a service request or registration request message, as described in clauses 5.38.2 and 5.38.4. The paging restriction information may indicate any one of the following:

a) All pages are limited; or (b)

B) All pages are limited except for pages for voice services (IMS voice); or (b)

C) All pages are limited except for certain PDU sessions; or (b)

D) All pages are limited except for pages for voice services (IMS voice) and certain PDU sessions.

■ Note 1: in case a), the UE is not expected to be paged for any purpose. In case b), the UE expects to page only voice services. In case c), the UE expects to page only for a specific PDU session. In case d), the UE expects to page for voice services and certain PDU sessions.

■ And (2) injection: in the case of roaming, the paging limit for voice services implied by bullets b) and d) depends on whether there is a protocol with the HPLMN that supports voice services over IMS. Thus, the support of paging restrictions in bullets b) and d) takes into account the IMS voice service protocol.

Additional details regarding UE behavior for MUSIM features may be found in 3GPP TS 24.501 V17.3.1.

Network Slice Specific Authentication and Authorization (NSSAA) is summarized as follows. NSSAA ensures that the registered UE will always have allowed slices because it is not subject to NSSAA, or if it is subject to NSSAA, authentication must first succeed before providing the UE with allowed Network Slice Selection Assistance Information (NSSAI).

When the slice is subject to NSSAA, the UE may receive a registration accept message without permission NSSAI, as described in 3GPP TS 24.501 V17.3.1. In this case, the message will contain a pending NSSAI and a "to perform NSSAA" indicator set to "to perform network slice specific authentication and authorization". The network then performs NSSAA the procedure and if there is at least one slice that was successful for it NSSAA, provides the slice to the UE as allowed NSSAI. Otherwise, if no slice is available due to NSSAA failure, the UE will be de-registered.

When the UE is waiting for the result of NSSAA (i.e., when the UE does not receive the allowed NSSAI), the UE is prohibited from initiating certain procedures (e.g., service request procedures) unless certain conditions are met. This behavior is described in 3GPP TS 24.501 V17.3.1.

"If REGISTRATION ACCEPT message:

a) Including a 5GS registration result IE with an "to execute NSSAA" indicator set to "to execute network slice specific authentication and authorization" and a "to execute NSSAA" indicator in the 5GS registration result IE;

b) Including pending NSSAI; and

C) Excluding the permissible NSSAI of the total number of the components,

The UE should delete the stored grant NSSAI (if any) as set forth in clause 4.6.2.2, and the UE:

a) Except for emergency services, the 5GSM procedure should not be started; and

B) The service request procedure should not be initiated except for the cases f) and i) in sub-clause 5.6.1.1;

c) Except for sending SMS, LPP message, location service message, SOR transparent container, UE policy container, UE parameter update transparent container or CIoT user data container, NAS transport procedure should not be started until the UE receives the allowed NSSAI;

Until the UE receives the grant NSSAI. "

For clarity, the case defined as the triggering of the service request procedure is shown below according to 3GPP TS 24.501 V17.3.1:

"the UE shall invoke the service request procedure if:

a) In a 5GMM-IDLE mode accessed by 3GPP, the UE receives a paging request from a network;

and (3) injection: as an implementation option, MUSIM-capable UEs are allowed to not invoke a service request to respond to a page based on information available in the page message (e.g., voice service indication).

B) In a 5GMM-CONNECTED mode of 3GPP access, the UE receiving a notification from the network with an access type indicating a non-3 GPP access;

c) In 5GMM-IDLE mode of 3GPP access, the UE has pending uplink signaling (except case i);

d) In 5GMM-IDLE mode of 3GPP access, the UE has pending uplink user data (except case j);

e) In either the 5GMM-CONNECTED mode or the 5GMM-CONNECTED mode with an RRC inactivity indication, the UE has pending user data due to the lack of user plane resources established for the PDU session for user data transmission;

f) In a 5GMM-IDLE mode of the non-3 GPP access, the UE receiving or having received an indication of the establishment of an access stratum connection between the UE and the network from a lower layer of the non-3 GPP access, in case T3346 is inactive, or upon expiration of T3346;

g) In a 5GMM-IDLE mode of 3GPP access, when the UE is in a 5GMM-CONNECTED mode of non-3 GPP access, the UE receives a notification from the network with an access type indicating 3GPP access;

h) As described in sub-clause 4.13.4.2 of 3GPP TS 23.502[9], a UE in 5GMM-IDLE, 5GMM-CONNECTED mode or 5GMM-CONNECTED mode with RRC inactivity indication of 3GPP access receives a request to perform emergency service fallback from an upper layer and performs emergency service fallback;

i) In the 5GMM-CONNECTED mode of 3GPP access or in the 5GMM-CONNECTED mode with RRC inactivity indication, the UE receives a fallback indication from the lower layer (see sub-clauses 5.3.1.2 and 5.3.1.4) and the UE has a pending NAS procedure other than a registration, service request or deregistration procedure;

j) In 5GMM-CONNECTED mode of 3GPP access or in 5GMM-CONNECTED mode with RRC inactivity indication, the UE receives a back-off indication from the lower layer (see sub-clauses 5.3.1.2 and 5.3.1.4) and the UE has pending uplink user data for PDU session, has already established user plane resources but has no pending NAS procedure;

k) A UE in 5GMM-CONNECTED mode and having only NAS signaling connection is using 5GS service with control plane CIoT 5GS optimization and has pending user data to send over user plane resources;

l) in 5GMM-IDLE mode of 3GPP access, the UE must request resources for V2X communication on PC5 (see 3GPP TS 23.287[6C);

m) a UE having MUSIM capabilities and in 5GMM-IDLE mode is requesting the network to remove the paging restriction;

n) in 5GMM-IDLE mode of 3GPP access, the UE must request resources for ProSe direct discovery on PC5 or ProSe direct communication on PC5 (see 3GPP TS 23.304[6E);

o) in 5GMM-CONNECTED mode, UE support MUSIM requesting the network to release NAS signaling connection and optionally including paging restriction; or (b)

P) in 5GMM-IDLE mode, the UE supports MUSIM, rejects a paging request from the network when responding to a page, requests the network to release the NAS signaling connection, and optionally includes paging restrictions. "

As can be seen from the above text, when no admission NSSAI is available, the exceptions to the initiation of the service request procedure include cases f) and i), which are:

"f) in 5GMM-IDLE mode of non-3 GPP access, the UE receiving or having received an indication of the establishment of an access stratum connection between the UE and the network from the lower layer of the non-3 GPP access, in case T3346 is inactive, or upon expiration of T3346;

…

i) In the 5GMM-CONNECTED mode of 3GPP access or in the 5GMM-CONNECTED mode with RRC inactivity indication, the UE receives a fallback indication from the lower layer (see sub-clauses 5.3.1.2 and 5.3.1.4) and the UE has a pending NAS procedure other than a registration, service request or deregistration procedure; "

Thus, when there is no allowed NSSAI available at the UE, all other cases (triggering of service request procedure) will be prohibited.

One of the modes of the UE in the fifth generation system (5 GS) is a fifth generation mobility management (5 GMM) -CONNECTED mode with an RRC inactivity indication. In this mode, it is considered that a Non Access Stratum (NAS) connection is established, and RRC is considered to be applied to the procedure of the rrc_idle state. Detailed behavior of the UE in 5GMM-CONNECTED mode with RRC inactivity indication is provided in section 5.3.1.4 of 3GPP TS 24.501 V17.3.1:

When the UE is in NB-N1 mode, the CONNECTED mode with RRC inactivity indication is not supported.

The UE is in a 5GMM-CONNECTED mode with RRC inactivity indication when:

a) A 5GMM-CONNECTED mode of 3GPP access at NAS layer; and

B) Rrc_inactive state at AS layer (see 3GPP TS 38.300[27).

Unless otherwise stated, the UE behavior in 5GMM-CONNECTED mode with RRC inactivity indication follows the UE behavior in 5GMM-CONNECTED mode of 3GPP access except that:

a) The UE should apply mobility restrictions; and

B) The UE shall perform PLMN selection procedure

Such as in the 5GMM-IDLE mode of 3GPP access.

After receiving an indication from the lower layer that the RRC connection has been suspended, the UE transitions from the 3 GPP-accessed 5GMM-CONNECTED mode to the 5GMM-CONNECTED mode with an RRC inactivity indication.

Note 0: when an indication is received from the lower layer that the RRC connection has been suspended, any pending procedures or uplink packets trigger a request to transition to the rrc_connected state from the lower layer. This is also the case when a pending procedure or uplink packet triggers a previous request to the lower layer to transition to the rrc_connected state.

When the following is the case:

a) Triggering of a procedure requiring sending a NAS message different from REGISTRATION REQUEST messages, wherein the NG-RAN-RCU bit of the 5GS update type IE is set to "UE radio capability update required"; or (b)

B) Uplink user data packets to be transmitted for a PDU session with suspended user plane resources;

A UE in 5GMM-CONNECTED mode with an RRC inactivity indication on 3GPP access requests a lower layer transition to rrc_connected state (see 3GPP TS 38.300[27).

Upon triggering the transmission REGISTRATION REQUEST of the NG-RAN-RCU bit of the 5GS update type IE set to "UE radio capability update required", the UE in 5GMM-CONNECTED mode with RRC inactivity indication shall move to 5GMM-IDLE mode for 3GPP access and proceed with the registration procedure for mobility and periodic registration described in sub-clause 5.5.1.3.2.

Upon receiving an indication from the lower layer that the UE has transitioned to the rrc_connected state, the UE should transition from the 5GMM-CONNECTED mode with an RRC inactivity indication to the 5GMM-CONNECTED mode of 3GPP access (see 3GPP TS 38.300[27).

Note 1: the AMF may be aware of the transition between the 5GMM-CONNECTED mode and the 5GMM-CONNECTED mode with an RRC inactivity indication for the UE (see 3gpp TS 23.502[9 ]).

Upon selection of an equivalent PLMN that is not the registered PLMN, the UE will trigger a transition from 5GMM-CONNECTED mode to 5GMM-IDLE mode with an RRC inactivity indication. Upon entering the new PLMN in the equivalent PLMN list, the UE should not trigger a transition from 5GMM-CONNECTED mode to 5GMM-IDLE mode with RRC inactivity indication.

As described in sub-clause 5.4.5.3.3, after receiving the REFRESH command from the UICC, the UE should trigger a transition from 5GMM-CONNECTED mode to 5GMM-IDLE mode with an RRC inactivity indication.

If the UE in the 5GMM-CONNECTED mode with RRC inactivity indication receives an indication from the lower layer that the RRC connection has been suspended, the UE should remain in the 5GMM-CONNECTED mode with RRC inactivity indication. If still needed, the UE should reinitiate any pending procedure that has triggered the transition to the rrc_connected state for the lower layer request.

When a UE in 5GMM-CONNECTED mode with RRC inactivity indication receives a back-off indication from the lower layer and the UE has no pending NAS procedure nor pending uplink user data for PDU sessions for which user plane resources have been established, the UE shall:

a) Entering a 5GMM-IDLE mode; and

B) A registration procedure for mobility and periodic registration update is initiated and the uplink data state IE is included in the REGISTRATION REQUEST message indicating a PDU session where user plane resources are active before a back-off indication (if any) is received (see sub-clause 5.5.1.3 for more details).

If the UE transitions to the rrc_connected state to the lower layer request at the beginning of the registration procedure, service request procedure, or deregistration procedure, the UE should, after a back-off indication from the lower layer:

-entering a 5GMM-IDLE mode;

-continuing the pending procedure; and

If the pending procedure is a SERVICE REQUEST or registration REQUEST procedure, the UE shall include an uplink data status IE in the SERVICE REQUEST message, CONTROL PLANE SERVICE REQUEST message or REGISTRATION REQUEST message indicating that the UE has pending user data (if any) PDU sessions without active user plane resources to send and PDU sessions with active user plane resources (if any) before receiving a back-off indication (see sub-clauses 5.5.1.3 and 5.6.1 for more details).

If the UE requests the lower layer to transition to the rrc_connected state for other reasons than initiation of the registration procedure, or other reasons than the service request procedure, or other reasons than cancellation of the registration procedure, the UE should, after a back-off indication from the lower layer:

1) Entering a 5GMM-IDLE mode;

2) The SERVICE REQUEST procedure is initiated and an uplink data state IE is included in the SERVICE REQUEST message or CONTROL PLANE SERVICE REQUEST message indicating that the user plane resources are active PDU sessions (if any) before receiving the back-off indication (if any) (see sub-clause 5.6.1 for further details). If the procedure triggering the transition to the rrc_connected state of the lower layer REQUEST is a UE-initiated NAS transport procedure and the UE has SMS, location service message or CIoT user data to send, the UE should also include SMS, location service message or CIoT user data in the CONTROL PLANE SERVICE REQUEST message, as in clause 6.5.2.2; and

3) Upon successful completion of the service request procedure, any pending procedures continue to be performed.

If a UE in 5GMM-CONNECTED mode with RRC inactivity indication receives a back-off indication from the lower layer and the UE has pending uplink user data for PDU session, has already established user plane resources, but no pending NAS procedure, the UE shall:

1) Entering a 5GMM-IDLE mode; and

2) The SERVICE REQUEST procedure is initiated and the uplink data state IE is included in a SERVICE REQUEST message or CONTROL PLANE SERVICE REQUEST message of a PDU session indicating that the user plane resource is active before the back-off indication is received (see sub-clause 5.6.1 for further details).

In the above case, when the UE receives the backoff indication from the lower layer, if the UE is in a non-allowed region or is not in an allowed region, the UE should behave as described in sub-clause 5.3.5.

If the UE in the 5GMM-CONNECTED mode with the RRC inactivity indication receives an indication of restoration of the RRC connection and failure from the lower layer, and:

a) If the lower layer indicates that access barring applies to all access categories except category 0 and 2, or that access barring applies to all access categories except category 0, the UE should:

1) Maintaining in a 5GMM-CONNECTED mode with an RRC inactivity indication;

b) Otherwise, the UE should:

1) Entering a 5GMM-IDLE mode; and

2) The registration procedure for mobility and periodic registration update for mobility (i.e., the 5GS registration type IE set to "mobility registration update" in REGISTRATION REQUEST message) is initiated for N1 NAS signaling connection recovery as described in sub-clause 5.5.1.3.2.

And (2) injection: an indication that the RRC connection from the lower layer has been released (due to "RRC recovery failure") may be regarded as an indication of RRC connection recovery failure.

The UE shall transition from 5GMM-CONNECTED mode with RRC inactivity indication to 5GMM-IDLE mode of 3GPP access upon receiving the following from the lower layer:

a) An indication to transition from the rrc_inactive state to the rrc_idle state; or (b)

B) Cell selection is indicated to the E-UTRAN or to another RAT supported by the UE.

If the UE in 5GMM-CONNECTED mode with RRC inactivity indication receives an indication from the lower layer regarding cell (re) selection to a different RAT supported by the UE, the UE shall initiate a registration procedure for mobility or a periodic registration update for mobility (i.e. a 5GS registration type IE set to "mobility registration update" in REGISTRATION REQUEST message) as described in sub-clause 5.5.1.3.2.

Upon receiving the AMF paging indication from the lower layer, the UE shall transition from the 5GMM-CONNECTED mode with RRC inactivity indication to the 5GMM-IDLE mode of 3GPP access and process the same AMF paging as the paging request received in the 5GMM-IDLE mode of 3GPP access, as described in sub-clause 5.6.1.

This section defines the current trigger that the UE (or NAS) will request the lower layer to resume the connection. After connection recovery (i.e., RRC enters rrc_connected state), NAS will enter 5GMM-CONECTED mode with RRC inactivity indication.

There are a number of problems associated with the above description. The first involves the impact on MUSIM features due to lack of admission NSSAI. As described above, UEs that do not have NSSAI allowed (e.g., due to an ongoing NSSAA procedure) will not be allowed to initiate a service request procedure unless the trigger is related to the current existing exception defined in 3GPP TS 24.501V17.3.1. However, since the use of MUSIM features is not currently part of these anomalies, a UE that requires release of its NAS connection to enable it to obtain service on another PLMN will face a delay because it cannot send a (control plane) service request message to request release of the NAS connection. This means that a UE that needs to leave its current PLMN to go to another PLMN and make a voice call will not be able to do so (i.e. a UE without admission NSSAI cannot request the network to release the NAS connection as required), as described above. This will lead to a negative user experience as the call will be delayed. Thus, the problem is that the current anomaly does not address MUSIM features, requiring an update.

The second problem relates to undefined UE behavior of MUSIM services when in 5GMM-CONNECTED mode with RRC inactivity indication. For a UE in the 5GMM-CONNECTED mode with an RRC inactivity indication, the UE may need to use MUSIM services (e.g., leave the current PLMN and use another PLMN, thereby using another USIM). This results in different UE behaviour and the network will not be able to predict how different UEs will behave. In other words, the UE will not be able to leave to another PLMN, and this will result in delays in service. This may also potentially cause different UEs to behave in an unexpected manner, which makes it impossible for the network to control how the UE will leave to obtain service in another PLMN. UEs often wish to follow standardized behavior, otherwise negative results will occur when different UEs behave differently (e.g. by generating signaling or leaving the network without notification, which may lead to wasteful transmission of downlink signaling). Furthermore, it is desirable to define UE behavior to reduce the delay in obtaining MUSIM services.

A third problem relates to undefined UE behavior of MUSIM services when in 5GMM-IDLE mode with a suspend indication. For a UE in 5GMM-IDLE mode with a suspend indication, the UE may need to use MUSIM services (e.g., leave the current PLMN and use another PLMN, thereby using another USIM). This results in different UE behaviour and the network will not be able to predict how different UEs will behave. UEs often wish to follow standardized behavior, otherwise negative results will occur when different UEs behave differently (e.g. by generating signaling or leaving the network without notification, which may lead to wasteful transmission of downlink signaling). Furthermore, it is desirable to define UE behavior to reduce the delay in obtaining MUSIM services.

According to an embodiment, a method of operating a MUSIM capable UE is provided. If the UE does not have admission NSSAI, then the service request procedure is admitted if the association trigger is related to MUSIM function.

If REGISTRATION ACCEPT message:

a) Including a 5GS registration result Information Element (IE), wherein the "NSSAA to perform" indicator is set to "to perform network slice specific authentication and authorization";

b) Including pending NSSAI; and

C) Excluding the permissible NSSAI of the total number of the components,

The UE may delete NSSAI (if any) of the stored permissions and may not initiate the service request procedure unless associated with the MUSIM function.

According to another embodiment, a method of operating a MUSIM capable UE is provided. If the UE is in 5GMM-CONNECTED mode with an RRC inactivity indication and experiences MUSIM requests, the UE sends a NAS message to request MUSIM service from the CONNECTED network or the UE autonomously enters 5GMM-IDLE mode.

The UE may request the network to release the NAS signaling connection. The request may include a paging restriction.

According to another embodiment, a method of operating a MUSIM capable UE is provided. If the UE is in Evolved Packet System (EPS) mobility management (EMM) -IDLE mode with a suspend indication and experiences MUSIM requests, the UE sends a NAS message to request MUSIM service from the connected network or the UE autonomously enters EMM-IDLE mode.

If the NAS message is

I) A service request message;

ii) control plane service request message and UE does not include any EPS Session Management (ESM) message container, NAS message container, EPS bearer context state information element or UE request type information element; or (b)

Iii) The service request message is extended and the service type information element indicates "packet service via S1", and the UE does not include any EPS bearer context state information element or UE request type information element, the message may not be transmitted.

MUSIM features may be one of the following: connection release, paging cause indication, refusal of paging request, paging restriction and deletion of stored paging restriction information.

According to another embodiment, there is provided an apparatus arranged to perform the method of any of the preceding aspects.

The term "MUSIM features" may relate to any of the following, or may refer to any of the following: connection release (e.g., for MUSIM), paging cause indication (e.g., for MUSIM), refusal of paging request (e.g., for MUSIM), or paging restriction (e.g., for MUSIM), or any combination of these features.

The details described herein may be applied in any combination and in any order. They may also be applied to UEs in S1 mode (if possible) or N1 mode or both (if possible). The S1 mode may refer to EPS and the N1 mode may refer to 5GS, so the network may refer to one or more nodes such as MME (in EPS) or AMF (in 5 GS).

Here, the request related to MUSIM features, or the request to obtain MUSIM service, may refer to the transmission of a NAS message optionally including a UE request type IE, wherein optionally an Information Element (IE) may be set to any value indicating "NAS signaling connection release" or "refusal of paging" or which may be defined for the IE in the future.

The UE allows initiation of the service request procedure for MUSIM even if no allowed NSSAI is available. When the UE receives the registration accept message, does not include allowed NSSAI, optionally includes pending NSSAI, and optionally includes a 5GS registration result IE with the "to perform NSSAA" indicator set to "to perform network slice specific authentication and authorization", then the UE may not be allowed to initiate (or may not initiate) the service request procedure unless the reason for this is for the MUSIM feature, e.g., the UE needs to be indicated/set to "NAS signaling connection release" or "reject paging" in the UE request type IE of the service request message or control plane service request message (or when any other new value related to the MUSIM feature is defined in the future).

Thus, when the UE does not have an allowed NSSAI, optionally due to an ongoing NSSAA procedure, the UE may verify the triggering of the service request procedure, based on which the UE may determine whether to initiate the procedure by sending an appropriate NAS message (e.g., a service request message or a control plane service request message). If the UE determines that the trigger is for MUSIM features, the UE may allow/initiate the procedure by sending a service request message or a control plane service request message. Otherwise, if the trigger is not related to MUSIM features, the UE may not initiate the procedure unless the trigger is for an existing exception as described in 3GPP TS 24.501V17.3.1.

The UE may first determine what action to take based on a configuration stored in the UE, which is preconfigured in the UE or received from the network (e.g., in any NAS message).

Fig. 1 is a flow chart illustrating example UE behavior according to an embodiment.

At S10, the UE receives a registration accept from the network without an allowed NSSAI message. At S20, a trigger for a service request is received or available.

As S30, the UE verifies whether the trigger is related to at least one MUSIM feature. If the trigger is not associated with at least one MUSIM feature, then at step S40, the process is blocked and flow returns to S10.

If the trigger is associated with at least one MUSIM feature, the procedure is allowed or initiated at S50 and the necessary NAS message is sent. For example, the NAS message may be a (control plane) service request message.

Another embodiment relates to obtaining MUSIM services when the UE is in 5GMM-CONNECTED mode with RRC inactivity indication. This provides new behavior for the UE to obtain USIM services. This may only apply to mobile-initiated requests for MUSIM features (i.e., requests that are initiated by the UE and not terminated at the UE and not initiated by the network).

Here, the request related to MUSIM features, or the request to obtain MUSIM services, may refer to the transmission of a NAS message, where the NAS message optionally includes a UE request type IE, and the IE may optionally be set to any value that indicates "NAS signaling connection release" or may be defined for the IE in the future.

In a first option, when a UE in 5GMM-CONNECTED mode with RRC inactivity indication needs to use MUSIM features/services, the UE may send a NAS message and include a UE request type IE. The IE may be set to "NAS signaling connection release" or any value defined for the IE in the future. The UE may first request the lower layer (e.g., RRC layer) to resume the connection and then optionally send a NAS message after resuming the connection.

The NAS message to be used may be any of the following: registration request message, service request message, or control plane service request message. At least in the case where the UE request type IE is set to "NAS signaling connection release", the UE may ensure that NAS messages (e.g., any of those listed above) may not include uplink data state IEs.

Fig. 2 is a flowchart showing how a UE may obtain MUSIM services in the 5GMM-CONNECTED mode with RRC inactivity indication, according to an embodiment.

At S110, the UE is in a 5GMM-CONNECTED mode with an RRC inactivity indication.

At S120, triggers for MUSIM services become available.

At S130, the UE sends or transmits a NAS message for MUSIM features (e.g., including a correspondingly set UE request type IE), or autonomously enters 5GMM-IDLE mode.

As described above, the NAS message that may be transmitted at S130 may be a registration request message, a service request message, or a control plane service request message, wherein the NAS message may include a UE request type IE set to an appropriate value.

When a UE (e.g., NAS) in 5GMM-CONNECTED mode with RRC inactivity indication requests a lower layer (e.g., RRC layer) to resume a connection for MUSIM services, and the UE then receives an indication from the lower layer that the resumption of RRC connection has failed, then the UE may behave as described below.

The UE may autonomously enter the 5GMM-IDLE mode. The UE may autonomously attempt to select another PLMN for the associated MUSIM service.

If the UE enters 5GMM-IDLE mode (e.g., as required in 3GPP TS 24.501 V17.3.1) after which the UE is required to trigger a NAS procedure (e.g., a registration procedure) for N1 NAS signaling connection restoration, the UE may determine to delay the procedure until MUSIM service is obtained (e.g., by the UE using another USIM or attempting to use another PLMN). Thus, the UE may delay the NAS procedure (e.g., registration procedure) until the UE terminates MUSIM the service, and the UE may later perform the procedure after using the service on another PLMN. Thus, after entering the 5GMM-IDLE mode as per the requirement of 3GPP TS 24.501 V17.3.1, the UE selects another PLMN to use the service, and after this is done, the UE may later reselect to that PLMN (where an indication of a restoration failure is received), and the UE may then perform NAS procedures (e.g., registration procedures) to restore the N1 NAS signaling connection.

If a UE in 5GMM-CONNECTED mode with RRC inactivity indication transitions to 5GMM-IDLE mode for any trigger (e.g., due to a trigger to send a registration request message in which the NG-RAN-RCU bit of the 5GS update type IE is set to "UE radio capability update required" or due to a fallback indication from the lower layer) and if the UE also requires another PLMN to be selected to obtain service on another USIM, the UE may delay the NAS procedure that needs to be sent on the current PLMN. The UE may first attempt to obtain the necessary service using another PLMN and then upon termination of the service (or after some other time has elapsed), the UE may return to that PLMN (where the UE initially needs to perform NAS procedures from 5GMM-IDLE mode) and perform the necessary NAS procedures. Thus, the UE may delay the procedure instead of immediately executing upon transition to the 5GMM-IDLE mode. This helps to reduce any delay in obtaining service from another PLMN.

The UE may operate as described above, with the respective steps performed in any combination or in any order.

In a second option, when a UE in 5GMM-CONNECTED mode with an RRC inactivity indication needs to use MUSIM features/services, the UE may autonomously enter 5GMM-IDLE mode (e.g., by locally releasing its NAS connection). The UE may then attempt to use MUSIM services on the other PLMN by reselecting to that PLMN once in 5GMM-IDLE mode. An example of such UE behavior is shown in S130 of fig. 2.

In another embodiment, MUSIM services may be obtained when the UE is in 5GMM-IDLE mode with a suspend indication.

Here, the request related to MUSIM features, or the request to obtain MUSIM services, may refer to the transmission of a NAS message, where the NAS message optionally includes a UE request type IE, and the IE may be set to any value that indicates "NAS signaling connection release" or "refusal to page" or may be defined for the IE in the future.

The following description applies to UEs in either the N1 mode (5 GS) or the S1 mode (EPS), so the appropriate NAS mode and NAS messages can be used accordingly.

In a first option, when a UE in (N1 mode) 5GMM-IDLE mode with a suspend indication needs to use MUSIM features/services, the UE may send a NAS message and include a UE request type IE. The IE may be set to "NAS signaling connection release" or "reject paging", or any value defined for the IE in the future. The UE may first request the lower layer (e.g., RRC layer) to resume the connection, and then the UE may optionally send a NAS message after resuming the connection.

The NAS message to be used may be any of the following: registration request message, service request message, or control plane service request message. At least in the case where the UE request type IE is set to "NAS signaling connection release", the UE may ensure that NAS messages (e.g., any of those listed above) may not include uplink data state IEs.

When a UE in EMM-IDLE mode with a suspend indication (S1 mode) needs to use MUSIM features/services, the UE may send a NAS message and include a UE request type IE. The IE may be set to "NAS signaling connection release" or "reject paging", or any value defined for the IE in the future. The UE may first request the lower layer (e.g., RRC layer) to resume the connection, and then the UE may optionally send a NAS message after resuming the connection.

The NAS message may be any one of the following messages: a tracking area update request message (combined), a service request message, a control plane service request message, or an attach request message (combined). At least in the case where the UE request type IE is set to "NAS signaling connection release", the UE may ensure that NAS messages (e.g., any of those listed above) may not include uplink data state IEs.

In a second option, when a UE in (N1 mode) 5GMM-IDLE mode with a suspend indication needs to use MUSIM features/services, the UE may autonomously enter 5GMM-IIDLE mode and attempt to use MUSIM features (e.g., on another PLMN).

When a UE in EMM-IDLE mode with a suspend indication (S1 mode) needs to use MUSIM features/services, the UE may autonomously enter EMM-IDLE mode and attempt to use MUSIM features (e.g., on another PLMN).

Fig. 3 is a flowchart showing how a UE may obtain MUSIM services when in 5GMM-IDLE/EMM-IDLE mode with a suspend indication, according to an embodiment.

At S210, the UE may be in a 5GMM-IDLE (or EMM-IDLE) mode with a suspension indication.

At S220, triggers for MUSIM services may become available.

At S230, the UE may send or transmit a NAS message for MUSIM features (e.g., including a correspondingly set UE request type IE), or the UE autonomously enters 5GMM-IDLE (or EMM-IDLE) mode, as described above for the second option.

As described above, the NAS message that may be transmitted in S230 may be a registration request message, a service request message, or a control plane service request message, wherein the NAS message may include a UE request type IE set to an appropriate value.

The embodiments described below apply to all cases and are not limited to only one mode. In S1 mode, when the UE transmits a control plane service request message or tracking area update request message including a UE request type IE (which may be set to any value), the UE may not set the "active flag" bit to a value indicating that radio bearer establishment is required/requested (i.e., the value may not be set to 1). The UE may set the value of this bit such that it indicates that no radio bearer establishment is needed/requested (i.e., the bit may be set to 0). This is to avoid setting up a user plane that leads to MUSIM features/service delays.

When the network (e.g., MME) receives the NAS message (e.g., control plane service request message or tracking area update request message) with the "active flag" bit set to a value such that the value indicates that radio bearer establishment is required/requested (i.e., the value is set to 1), the network (e.g., MME) may ignore the bit or treat the bit as a value set to a value indicating that radio bearer establishment is not required/requested (i.e., treat the bit as set to 0), and thus the network (e.g., MME) may not establish user plane resources (or may not establish radio bearer resources and/or other corresponding EPS bearer resources for the user plane).

When a network (e.g., MME) receives a NAS message (e.g., a control plane service request message or a tracking area update request message), wherein:

● Setting the "active" flag bit to a value such that the value indicates that radio bearer establishment is required/requested (i.e., the value is set to 1), and

● The UE request type IE is included in the NAS message such that the request type indicates "NAS signaling connection release" (or alternatively "reject paging" or any value that may be defined in the future)

The network (e.g., MME) may ignore the bit or treat the bit as if it were set to a value indicating that no radio bearer establishment is needed/requested (i.e., treat the bit as if it were set to 0). Thus, the network (e.g., MME) may not establish user plane resources (or may not establish radio bearer resources and/or other corresponding EPS bearer resources for the user plane).

Alternatively, when the NAS message includes a UE request type IE such that the request type indicates "NAS signaling connection release", the MME may simply ignore the value of the "active" flag bit in the NAS message regardless of its value, and thus, the MME may always treat this bit as an indication value 0 even if the bit indicates value 1. Thus, the network (e.g., MME) may not establish user plane resources (or may not establish radio bearer resources and/or other corresponding EPS bearer resources for the user plane).

Alternatively, whenever the MME receives a NAS message (e.g., a control plane service request message or tracking area update request message) with the "active" flag set to 1 in the appropriate IE (e.g., in a control plane service type IE or EPS update type IE, respectively), the MME may verify whether the NAS message also contains a UE request type IE. The IE may be set to a value (or any other value) indicating "NAS signaling connection release". If the NAS message contains a UE request type IE (i.e., if the NAS message also indicates that NAS signaling can be released), the MME may ignore the value of the "active" flag bit, regardless of its value, or even if the bit is set to a value of 1. Thus, under the above conditions, the MME may consider the value of the "active" flag to be 0, and therefore the MME may not establish user plane resources for the EPS bearer.

In other words, if the MME verifies the NAS message in which the "active" flag is set to 1 and determines that the UE request type IE is not included, or the UE request type IE is included but does not indicate "NAS signaling connection release", the MME may establish user plane resources for the EPS bearer of the UE. Otherwise, the MME may not establish user plane resources.

Thus, the following MME behaviour can be defined. If the "active" flag is set in the tracking area update request message, and:

● MME does not use control plane Consumer Internet of things (CIoT) EPS optimization; and

● The UE request type IE is not included in the tracking area update request message or the UE request type IE is included in the tracking area update request message but the request type is not set to "NAS signaling connection release";

The MME should re-establish the radio bearer and S1 bearer for all active EPS bearer contexts.

If the "active" flag is set in the tracking area update request message, and:

● MME uses control plane CIoT EPS optimization,

● The UE request type IE is not included in the tracking area update request message or the UE request type IE is included in the tracking area update request message but the request type is not set to "NAS signaling connection release";

the MME will re-establish the radio bearer and S1 bearer for all active EPS bearer contexts associated with PDN connections established without control plane only indication.

If the "active" flag is set in the tracking area update request message, which does not contain a UE request type IE with request type indication "NAS signaling connection release", and the MME does not use control plane CIoT EPS optimization, the MME can re-establish the radio and S1 bearers for all active EPS bearer contexts. If the "active" flag is set in the tracking area update request message, which does not contain a UE request type IE with request type indication "NAS signaling connection release", and the MME uses control plane CIoT EPS optimization, the MME will re-establish radio bearers and S1 bearers for all active EPS bearer contexts associated with PDN connections established without control plane only indication.

The above steps also apply to any other NAS message in which an "active" flag may be set/sent/included.

Similar proposals may be applied to AMFs in 5GS, where the AMFs may establish user plane resources only if NAS messages (e.g. registration request messages, service request messages or control plane service request messages) meet the following conditions (when the UE requests to do so by using an uplink data state IE):

● Does not include a UE request type IE, or

● The UE request type IE is included, but the request type is not set to "NAS signaling connection release".

Thus, if the UE request type IE is included in the NAS message such that the request type is set to "NAS signaling connection release" (or any other value), the AMF may not request the SMF to establish user plane resources for the UE, regardless of the value of the corresponding bit in the uplink data state IE (i.e., even if the bit is set such that the request to establish user plane resources for the corresponding PDU session identification).

The above details may also apply to the allowed PDU session state IE.

Alternatively, when the AMF receives the uplink data state IE (and/or the allowed PDU session state IE) such that any bit in the IE is set to a value of 1 (i.e., there is at least one PDU session identity: a (re) establishment of user plane resources is being requested for the PDU session identity), then the AMF may further verify whether the UE request type IE is included, and if so, what value the request type indicates. If the IE is included and the request type is set to "NAS signaling connection release" (or alternatively any other value), the AMF may not instruct/request the SMF to establish user plane resources for a given PDU session identity for which this bit in the uplink data state IE is set to 1. However, if the IE is not included, or if the IE is included but the request type is not set to "NAS signaling connection release", the AMF may request/indicate to the SMF to establish user plane resources for the UE (assuming other conditions not to do so do not apply). The above proposal may be applicable to any NAS message.

The core network node (e.g., MME or AMF) may be configured to operate such that if the core network receives:

● Any NAS message with the "active" flag set to 1 (i.e., requesting user plane resource activation) and the UE request type IE (for which the request type is set to "NAS signaling connection release") may then the core network node (e.g., MME) may determine to establish user plane resources and optionally ignore the request to release the NAS signaling connection (i.e., user plane resource establishment request overrides the request to release the NAS connection). The MME may additionally send EMM status messages to inform the UE of the error in sending the two conflicting requests,

● Including any of the uplink data state IEs or the allowed PDU session state IEs such that one or more bits in the IEs are set to any NAS message requesting the establishment of a value of user plane resources for the PDU session (identity), the AMF may determine to establish the user plane resources and optionally ignore the request to release the NAS signaling connection (i.e., the user plane resource establishment request covers the request to release the NAS connection). The AMF may additionally send 5GMMSTATUS a message to inform the UE of the error of sending the two conflicting requests.

Thus, in general, the core network node may be configured to prioritize establishment of user plane resources (via an active flag or uplink data state IE/allowed PDU session state IE for MME or AMF, respectively) before NAS connection release, when both are requested, and vice versa (i.e. as described above, when NAS connection release and user plane resource establishment are requested in the same message, the core network node prioritizes NAS links before establishment of user plane resources). The core network behavior may be implementation-based and may be any of the options presented herein.

Furthermore, when the UE wants to request establishment of user plane resources by:

● Setting the "active" flag to1 in any NAS message (e.g., control plane service request message or tracking area update request message), the UE may ensure that the NAS message does not include a UE request type IE, such that the request type indicates "NAS signaling connection release". In other words, for any NAS message containing an "active" flag with a value of 1, the UE request type IE may be included, but its value cannot be set to "NAS signaling connection release". In this case, it may be preferable not to transmit the UE request type IE.

● Requesting establishment of user plane resources via uplink data state IEs or via allowed PDU session state IEs (e.g., when the UE uses these IEs and sets a bit to 1 such that the UE is requesting establishment of user plane resources), the UE may ensure that the NAS message does not include a UE request type IE such that the request type indicates "NAS signaling connection release". In other words, for any NAS message containing an uplink data state IE or an allowed PDU session state IE, such that any bit is set to 1 (i.e., the UE is requesting to establish user plane resources), the UE request type IE may be included, but its value cannot be set to "NAS signaling connection release". In this case, it may be preferable not to transmit the UE request type IE.

For cases b and m in clause 5.6.1.1,

-If the UE has pending IP, non-IP or ethernet user data to send over the user plane radio bearer, the UE may set the control plane service type of the control plane service request message to "mobile originated request" and set the "active" flag in the control plane service type IE to 1. The UE should not include any ESM message container or NAS message container IE in the control plane service request message. Furthermore, for case m, the control plane service request message should not include a UE request type IE with a request type indicating "NAS signaling connection release". Similarly, in 5GS (i.e., in N1 mode), when the UE wants to request establishment of user plane resources via an uplink data state IE (or an allowed PDU session state IE that may be used to transport a session between non-3 GPP access and 3GPP access), the UE may not include a UE request type IE with request type set to "NAS signaling connection release". This applies to all NAS messages such as service request messages, registration request messages and control plane service request messages.

Further, for case e) of the service request procedure, the service request message may not include the UE request type IE with a request type indicating "NAS signaling connection release".

Further, for case k) of the service request procedure, the control plane service request message may not include the UE request type IE with a request type indicating "NAS signaling connection release".

Fig. 4 is a diagram illustrating a structure of a UE according to an embodiment.

As shown in fig. 4, the UE may include a transceiver 410, a memory 420, and a processor 430. The transceiver 410, the memory 420, and the processor 430 of the UE may operate according to the communication method of the UE described above. However, components of the UE are not limited thereto. For example, the UE may include more or fewer components than those described above. Further, the processor 430, the transceiver 410, and the memory 420 may be implemented as a single chip. Further, the processor 430 may include at least one processor. Further, the UE of fig. 4 corresponds to the UEs of fig. 1 to 3.

The transceiver 410 is collectively referred to as a UE receiver and a UE transmitter, and may transmit/receive signals to/from a base station or network entity. Signals transmitted to or received from a base station or network entity may include control information and data. Transceiver 410 may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal and an RF receiver for amplifying low noise and down-converting the frequency of a received signal. However, this is merely an example of transceiver 410, and components of transceiver 410 are not limited to RF transmitters and RF receivers.

In addition, the transceiver 410 may receive a signal through a wireless channel and output it to the processor 430, and transmit the signal output from the processor 430 through the wireless channel.

The memory 420 may store programs and data required for the operation of the UE. Further, the memory 420 may store control information or data included in a signal obtained by the UE. The memory 420 may be a storage medium such as a ROM, RAM, hard disk, CD-ROM, DVD, or a combination of storage media.

Processor 430 may control a series of processes such that the UE operates as described above. For example, the transceiver 410 may receive a data signal including a control signal transmitted by a base station or a network entity, and the processor 430 may determine a result of receiving the control signal and the data signal transmitted by the base station or the network entity.

Fig. 5 is a diagram showing the structure of a base station according to an embodiment.

As shown in fig. 5, a base station may include a transceiver 510, a memory 520, and a processor 530. The transceiver 510, memory 520 and processor 530 of the base station may operate according to the communication methods of the base station described above. However, the components of the base station are not limited thereto. For example, a base station may include more or fewer components than those described above. Further, the processor 530, the transceiver 510, and the memory 520 may be implemented as a single chip. Further, the processor 530 may include at least one processor. Furthermore, the base station of fig. 5 supports communication for the UEs of fig. 1-3. For example, the base station of fig. 5 supports NAS procedures between the core network (e.g., MME) and the UE of fig. 3-5.

The transceiver 510 is collectively referred to as a base station receiver and a base station transmitter, and may transmit/receive signals to/from a terminal (UE) or a network entity. The signals transmitted to or received from the terminal or network entity may include control information and data. The transceiver 510 may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for amplifying low noise and down-converting the frequency of a received signal. However, this is merely an example of transceiver 510, and components of transceiver 510 are not limited to RF transmitters and RF receivers.

The transceiver 510 may receive signals through a wireless channel and output them to the processor 530, and transmit signals output from the processor 530 through the wireless channel.

The memory 520 may store programs and data required for the operation of the base station. Further, the memory 520 may store control information or data included in a signal obtained by the base station. The memory 520 may be a storage medium such as a ROM, RAM, hard disk, CD-ROM, DVD, or a combination of storage media.

Processor 530 may control a series of processes such that the base station operates as described above. For example, the transceiver 510 may receive a data signal including a control signal transmitted by a terminal, and the processor 530 may determine a result of receiving the control signal and the data signal transmitted by the terminal.

According to an embodiment, a method of operating a User Equipment (UE) with multiple universal user identity module (MUSIM) capability in a wireless communication system, the method includes initiating a service request procedure if the UE does not have allowed Network Slice Selection Assistance Information (NSSAI) and an associated trigger is related to MUSIM features.

According to an embodiment, the method further comprises deleting NSSAI of the stored permissions; and excluding the service request procedure unless associated with the MUSIM feature, in the case that the registration accept message includes a fifth generation system (5 GS) registration result Information Element (IE) with an indicator that Network Slice Specific Authentication and Authorization (NSSAA) is to be performed, including pending NSSAI, and not including allowed NSSAI.

According to an embodiment, the method further comprises sending a non-access stratum (NAS) message to request MUSIM service from the CONNECTED network or to enter a 5GMM-IDLE mode in case the UE is in a fifth generation mobility management (5 GMM) -CONNECTED mode with Radio Resource Control (RRC) inactivity indication and a MUSIM request is received.

According to an embodiment, the method further comprises requesting the network of the connection to release the NAS signaling connection.

According to an embodiment, the method further comprises requesting paging restriction from the connected network.

According to an embodiment, the method further comprises sending a NAS message to request MUSIM service from the connected network or entering EMM-IDLE mode in case the UE is in Evolved Packet System (EPS) mobility management (EMM) -IDLE mode with a suspension indication and receives MUSIM the request.

According to an embodiment, in case the NAS message comprises at least one of a service request message, a control plane service request message or an extended service request message, no NAS message is sent.

According to an embodiment, in case the UE does not comprise an EPS Session Management (ESM) message container, a NAS message container, an EPS bearer context state information element or a UE request type information element, no NAS message is sent.

According to an embodiment, in case the service type information element indicates packet service via S1 and in case the UE does not comprise an EPS bearer context state information element or a UE request type information element, no NAS message is sent.

According to an embodiment MUSIM features one of connection release, paging cause indication, refusal of paging request, paging restriction and deletion of stored paging restriction information.

According to an embodiment, a User Equipment (UE) having Multiple Universal Subscriber Identity Module (MUSIM) capabilities in a wireless communication system, and the UE includes a transceiver and at least one processor coupled with the transceiver, initiates a service request procedure in the event that the UE does not have allowed Network Slice Selection Assistance Information (NSSAI) and an associated trigger is related to MUSIM features.

In accordance with an embodiment, where the registration accept message includes a fifth generation system (5 GS) registration result Information Element (IE) with an indicator indicating that network slice specific authentication and authorization is to be performed (NSSAA), including pending NSSAI, and not including allowed NSSAI, the at least one processor is configured to delete the stored allowed NSSAI and exclude service request procedures unless associated with the MUSIM feature.

In the case that the UE is in a fifth generation mobility management (5 GMM) -CONNECTED mode with a Radio Resource Control (RRC) inactivity indication and receives MUSIM a request, the at least one processor is configured to send a non-access stratum (NAS) message to request MUSIM service from the CONNECTED network or autonomously enter the 5GMM-IDLE mode.

According to an embodiment, the at least one processor is configured to control the network to which the transceiver requests the connection to release the NAS signaling connection.

According to an embodiment, the at least one processor is further configured to request paging limits from the connected network.

According to an embodiment, in case the UE is in Evolved Packet System (EPS) mobility management (EMM) -IDLE mode with a suspension indication and receives MUSIM request, the at least one processor is configured to send a NAS message to request MUSIM service from the connected network or autonomously enter EMM-IDLE mode.

According to an embodiment, if the NAS message includes at least one of a service request message, a control plane service request message, or an extended service request message, the NAS message is not transmitted.

According to an embodiment, in case the UE does not comprise an EPS Session Management (ESM) message container, a NAS message container, an EPS bearer context state information element or a UE request type information element, no NAS message is sent.

According to an embodiment, in case the service type information element indicates packet service via S1 and in case the UE does not comprise an EPS bearer context state information element or a UE request type information element, no NAS message is sent.

According to an embodiment MUSIM features one of connection release, paging cause indication, refusal of paging request, paging restriction and deletion of stored paging restriction information.

Embodiments may be applied in different combinations or sequences and may be applied in at least one mode only. Examples of specific modes are not to be considered as limitations of the embodiments, but rather as examples.

At least some of the embodiments described herein may be constructed, in part or in whole, using special purpose hardware. Terms such as "component," "module," or "unit" as used herein may include, but are not limited to, a hardware device such as a circuit in the form of a discrete or integrated component, a Field Programmable Gate Array (FPGA), or an application-specific integrated circuit (ASIC) that performs certain tasks or that provides related functionality. The described elements may be configured to reside on tangible, persistent, addressable storage media and may be configured to execute on one or more processors. For example, these functional elements may include components such as software components, object-oriented software components, class components and task components, processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. Although embodiments have been described with reference to components, modules and units discussed herein, such functional elements may be combined into fewer elements or separated into additional elements. Various combinations of optional features have been described herein, and it should be appreciated that the described features may be combined in any suitable combination. In particular, features of any one example may be combined with features of any other embodiment as appropriate, unless such combination is mutually exclusive. In this specification, the terms "comprising" or "including" are intended to include the stated components, but not exclude other components.

All of the features disclosed herein (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed herein (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

While the present disclosure has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (15)

1. A method of operating a User Equipment (UE) having Multiple Universal Subscriber Identity Module (MUSIM) capabilities in a wireless communication system, the method comprising:

In the event that the UE does not have allowed Network Slice Selection Assistance Information (NSSAI) and the associated trigger is related to the MUSIM feature, a service request procedure is initiated.

2. The method of claim 1, the method further comprising:

delete stored permissions NSSAI; and

In the registration accept message:

Comprising a fifth generation system (5 GS) registration result Information Element (IE) with an indicator indicating that a Network Slice Specific Authentication and Authorization (NSSAA) is to be performed,

Including pending NSSAI, and

In the case where the allowed NSSAI is not included,

The service request procedure is excluded unless associated with MUSIM features.

3. The method of claim 1, the method further comprising:

In case the UE is in a fifth generation mobility management (5 GMM) -CONNECTED mode with Radio Resource Control (RRC) inactivity indication and receives MUSIM a request, a non-access stratum (NAS) message is sent to request MUSIM service from the CONNECTED network or to enter 5GMM-IDLE mode.

4. A method according to claim 3, the method further comprising:

the network requesting the connection releases the NAS signaling connection.

5. The method of claim 4, the method further comprising:

Paging restrictions are requested from the connected network.

6. The method of claim 1, the method further comprising:

In case the UE is in Evolved Packet System (EPS) mobility management (EMM) -IDLE mode with a suspension indication and receives MUSIM request, a NAS message is sent to request MUSIM service from the connected network or to enter EMM-IDLE mode.

7. The method of claim 6, wherein the NAS message is not sent if the NAS message includes at least one of:

the service request message is sent to the server,

Control plane service request message, or

An extended service request message.

8. The method of claim 6, wherein the NAS message is not sent in the event that the UE does not include an EPS Session Management (ESM) message container, a NAS message container, an EPS bearer context state information element, or a UE request type information element.

9. The method of claim 6, wherein the NAS message is not transmitted in case the service type information element indicates a packet service via S1 and in case the UE does not include an EPS bearer context state information element or a UE request type information element.

10. The method of claim 1, wherein MUSIM features are one of connection release, paging cause indication, refusal of paging request, paging restriction, and deletion of stored paging restriction information.

11. A User Equipment (UE) with Multiple Universal Subscriber Identity Module (MUSIM) capability in a wireless communication system, the UE comprising:

A transceiver; and

At least one processor coupled to the transceiver,

Wherein the service request procedure is initiated in case the UE does not have allowed Network Slice Selection Assistance Information (NSSAI) and the associated trigger is related to the MUSIM feature.

12. The UE of claim 11, wherein, in the registration accept message:

Comprising a fifth generation system (5 GS) registration result Information Element (IE) with an indicator indicating that a Network Slice Specific Authentication and Authorization (NSSAA) is to be performed,

Including pending NSSAI, and

In the case where the allowed NSSAI is not included,

The at least one processor is configured to delete the stored permissions NSSAI and exclude service request procedures unless associated with the MUSIM feature.

13. The UE of claim 11, wherein, with the UE in a fifth generation mobility management (5 GMM) -CONNECTED mode with Radio Resource Control (RRC) inactivity indication and receiving MUSIM request, the at least one processor is configured to send a non-access stratum (NAS) message to request MUSIM service from a CONNECTED network or autonomously enter a 5GMM-IDLE mode.

14. The UE of claim 13, wherein the at least one processor is configured to control a network to which the transceiver requests a connection to release the NAS signaling connection.

15. The UE of claim 14, wherein the at least one processor is further configured to request paging restrictions from a connected network.