Abstract: A method for handling a collision of a UE-requested PDU session establishment procedure and a network-requested PDU session release procedure is proposed. When a PDU SESSION ESTABLISHMENT REQUEST message indicates that the UE-requested PDU session establishment request procedure is to handover an existing PDU session between 5G 3GPP access and 5G non-3GPP access, the UE proceeds with the network-requested PDU session release procedure and aborts the UE-requested PDU session establishment procedure. Otherwise, the UE ignores a received PDU SESSION RELEASE COMMAND message and proceeds with the UE-requested PDU session establishment procedure.

Abstract: A method for handling multi-access (MA) Protocol data unit (PDU) session release is proposed. An MA PDU session uses one 3GPP access network or one non-3GPP access network at a time, or simultaneously one 3GPP access network and one non-3GPP access network. Upon receiving a PDU session release command message including an access type, the user equipment (UE) transmits a PDU session release complete message or a 5G session management (5GSM) status message to the 5G system (5GS). In addition, the UE determines the user plane resources of the MA PDU session on the access indicated in the access type as released, or determines the MA PDU session as released, depending on the access indicated in the access type and the access(es) over which the user plane resources of the MA PDU session are established.

Abstract: A method for evaluation of UE route selection policy (URSP) rules is proposed. URSP is used by a UE to determine if a detected application can be associated to an established PDU session, can be offloaded to non-3GPP access outside a PDU session, or can trigger the establishment of a new PDU session. The UE first finds a non-default URSP rule with a matching traffic descriptor to the application. Then, the UE selects a route selection descriptor including a preferred access type from a list of RSDs of the non-default URSP rule. After that, the UE matches or establishes a Protocol Data Unit (PDU) session for the application by ignoring the preferred access type or using the preferred access type.

Abstract: A method for handling a reactivation request from the network for an MA PDU session with session and service continuity (SSC) mode 3 is proposed. When UE receives a PDU SESSION MODIFICATION COMMAND message which includes 5GSM cause #39 “reactivation requested” for an existing MA PDU session, UE handles the network-requested PDU session modification procedure, and UE re-initiates the UE-requested PDU session establishment procedure with a new MA PDU session ID. UE determines how to proceed with a PDU session reestablishment procedure for the new MA PDU session based on different scenarios of UE registration and user plane resources of the existing MA PDU session, and/or also based on whether the PDU SESSION MODIFICATION COMMAND message is sent over 3GPP access type or non-3GPP access type.

Abstract: A method of handling multi-access (MA) Protocol data unit (PDU) session handover is proposed. A UE and network can support Access Traffic Steering Switching and Splitting (ATSSS) functionalities to distribute traffic over 3GPP access and non-3GPP access for the established MA PDU session. An ATSSS-Supported UE first establishes a MA PDU Session on both 3GPP and non-3GPP access in a currently registered PLMN which is an ATSSS-Supported network. The UE then moves from the ATSSS-Supported network to an ATSSS-not-Supported network and finally reaches another ATSSS-Supported network. In one novel aspect, a solution is provided on how to handle the ongoing MA PDU Session with two accesses under handover scenarios between ATSSS-Supported and ATSSS-not-Supported networks. Furthermore, if the ongoing MA PDU Session cannot handover, a solution is provided on how to handle the MA PDU Session.

Abstract: A method for a User Equipment (UE) to enhance Voice Domain Management (VDM) for IP Multimedia Subsystem (IMS) voice provided over a 5G network is provided. The UE receives an indication that causes it to not disable the Evolved-Universal Terrestrial Radio Access (E-UTRA) capability for a Public Land Mobile Network (PLMN), before or after selecting a Next Generation-Radio Access Network (NG-RAN) cell in the PLMN with the UE's usage setting being set to voice centric. The UE enables the E-UTRA capability or keeps the E-UTRA capability enabled in response to the indication.

Abstract: A method can include receiving a non-access stratum (NAS) message for establishing or modifying a protocol data unit (PDU) session at a user equipment (UE) from a core network, determining whether there is a quality of service (QoS) flow description resulting from the establishment or modification of the PDU session that is associated with a guaranteed bit rate (GBR) QoS flow of the PDU session, and invalid, and when it is determined that there is the invalid QoS flow description associated with the GBR QoS flow of the PDU session, performing an error handling operation.

Abstract: A method of handling parameters of a subscribed network upon accessing a selected Stand-alone Non-Public Network (SNPN) using credentials from a credential holder is proposed. The UE selects an SNPN using a configured list of subscriber data, e.g., based on SNPN selection parameters contained in a selected entry of the list of subscriber data, or selects the SNPN based on SNPN selection parameters associated with a PLMN subscription of a USIM card. The UE accesses the selected SNPN using credentials supplied by a subscribed network, which is identified by the selected entry or by the USIM card. Upon successful registration to the selected SNPN, the UE applies a list of 3GPP PS_Data_Off exempt services that is different from a configured list of 3GPP PS_Data_Off exempt services associated with the selected entry, and evaluates a URSP that is different from the pre-configured URSP of the subscribed network.

Abstract: Methods and apparatus are provided for providing UE EPS capability information and receiving non-access stratum (NAS) security algorithm information for an interworking procedure in the 5GS network. In one novel aspect, the UE provides the UE EPS capability information in cleartext before the security mode procedure, and the NAS security algorithm information is included in a security mode command message during the security mode procedure. In one embodiment, the UE EPS capability information is an S1 mode indicator or the 5GMM capability information including the Si mode indicator. In another novel aspect, the network provides the NAS security algorithm information before interworking procedure from 5GS to LTE. In one embodiment, the network provides the NAS security algorithm information in the Registration Accept message. In another embodiment, the network provides the NAS security algorithm information in handover procedure from the 5GS to LTE.

Abstract: A method for UE route selection policy (URSP) rule matching regarding S-NSSAI and PDU session type is proposed. When an application is executed, a UE finds an RSD of a matching URSP rule, and the association of the application with an existing PDU session should have some exceptions. In one example, regarding S-NSSAI, if there's only a single allowed S-NSSAI or the UE is aware of the default S-NSSAI, the UE can associate the PDU session with the application where the existing PDU session is established with an S-NSSAI provided by the UE, but the RSD doesn't include any S-NSSAI. In another example, regarding PDU session type, the PDU session type IPv4v6 in the RSD can match with PDU session type IPv4 or IPv6 of the PDU session, which was established when the UE requested IPv4v6 during the PDU session establishment.

Abstract: A method for enhancing User Equipment (UE) handling of Non-Access Stratum (NAS) signaling connection release is provided. A UE establishes a NAS signaling connection with a mobile communication network belonging to a Public Land Mobile Network (PLMN). The UE receives a NAS message including a Closed Access Group (CAG) information list from the mobile communication network while camping on a CAG cell. The UE starts a timer in response to determining that no entry for the current PLMN is included in the received CAG information list. The UE locally releases the established NAS signaling connection upon expiry of the timer.

Abstract: A connection recovery method for recovering a connection between a communications apparatus and a data network includes: receiving a first message indicating a non-3GPP access from the 3GPP network device in a CM-IDLE state in the non-3GPP access network; transmitting a second message to the 3GPP network device via 5GMM protocol over 3GPP control plane to establish the user plane resources for the non-3GPP PDU session; receiving a third message indicating that the user plane resources cannot be reestablished; and transmitting to the 3GPP network device a service request message via the 5GMM protocol over the 3GPP Internet PDU session of 3GPP user plane to reestablish the user plane resources, or a PDU session establishment request message via 5GSM protocol over the 3GPP control plane to handover the non-3GPP PDU session from the non-3GPP access network to the 3GPP access network in response to the third message.

Abstract: A method for 5G Session Management (5GSM) handling of network rejection not due to congestion control is provided. A User Equipment (UE) receives a 5GSM reject message from a mobile communication network. The 5GSM reject message indicates a network rejection not due to congestion control. The UE associates a back-off timer with a Home Public Land Mobile Network (HPLMN) Single-Network Slice Selection Assistance Information (S-NSSAI). The UE prevents itself from sending a 5GSM request message for the same HPLMN S-NSSAI that is associated with the back-off timer.

Abstract: The invention relates to a method for reducing NAS signaling of LCS and LPP procedures initiated by UE in EMM idle mode and EMM registration state. The disclosed method involves multiple methods of encapsulating LPP/LCS messages into control plane service requests. This makes it possible for the UE and eNB to transmit LPP/LCS messages during the RRC connection establishment procedure, and can be regarded as an extension of the control plane EPS CIoT optimization.

Abstract: A method to facilitate onboarding registration via an onboarding network (ON) that is a stand-alone non-public network (ON-SNPN) is proposed. A UE is preconfigured with default UE credentials for Onboarding. UE discovers and selects an ON-SNPN and registers to the ON-SNPN using default UE credentials. Both user plane (UP) and control plane (CP) provisioning procedure can be used to obtain the SNPN credentials from a subscriber owner (SO) via an ON-SNPN access connectivity. In accordance with one novel aspect, when UE sends a registration request for UE onboarding registration, the registration request comprises information for registration type (e.g., SNPN ONBOARDING), and UE supported provisioning procedure (e.g., CP, UP, or both). Upon successful registration, UE follows the supported provisioning procedure (i.e., CP or UP) decided by the ON-SNPN to obtain the SNPN credentials from the SO-SNPN via the ON-SNPN access connectivity to a Provisioning Server (PVS).

Abstract: Various examples and schemes pertaining to error handling on missing configuration for inter-system change in mobile communications are described. An apparatus performs a protocol data unit (PDU)-related procedure with a wireless network. The apparatus detects whether there is an error in the PDU-related procedure and the apparatus handles the error in response to detecting the error in the PDU-related procedure.

Abstract: Solutions pertaining to user equipment (UE) and network behavior at and after a network disaster in mobile communications are proposed. An apparatus, implemented in or as a UE, determines whether a disaster condition is met with respect to a first public land mobile network (PLMN). The apparatus then selects a second PLMN according to information listing one or more PLMNs which are allowed to be selected by the UE when the disaster condition is met. The apparatus also attempts a registration in the second PLMN.

Abstract: A method for synchronizing evolved packet system (EPS) bearer context status between a user equipment (UE) and a network can include locally deactivating an EPS bearer context of a packet data network (PDN) connection at the UE while the UE operates in S1 mode without notifying the network serving the UE, wherein interworking to a fifth generation system (5GS) is supported for the deactivated EPS bearer context, and upon inter-system change from S1 mode to N1 mode, including an EPS bearer context status information element (IE) in a registration request message indicating which EPS bearer contexts are active in the UE before the inter-system change.

Abstract: A method, executed by a User Equipment (UE) communicatively connected to a mobile communication network, is provided. The method may include the following steps: receiving a first 5G Session Management (5GSM) message including one mapped Evolved Packet System (EPS) bearer context for an inter-system change from the mobile communication network; determining whether the mapped EPS bearer context has invalid or missing parameters; and sending a second 5GSM message to the mobile communication network to delete the mapped EPS bearer context in response to the mapped EPS bearer context has one or more invalid or missing parameters.

Abstract: Solutions for data network name (DNN) selection when user equipment (UE) route selection policy (URSP) rule is applied in evolved packet system (EPS) with respect to user equipment and network apparatus in mobile communications are described. An apparatus may start an application in an EPS network. The apparatus may select a URSP rule from one or more configured URSP rules by matching a traffic descriptor (TD) of the URSP rule with the application. The apparatus may determine whether a data network name (DNN) or access point name (APN) included in a route selection descriptor (RSD) is a local area data network (LADN) DNN or APN. The apparatus may skip the RSD in an event that the DNN or APN is the LADN DNN or APN. The apparatus may evaluate a next RSD or a next URSP rule in case that the next RSD or the next URSP rule is available.