Abstract: The present invention provides methods and devices for a network to inform a user equipment which network slice is attached successfully and which network slice is prohibited to attach.

Abstract: A communication device of handling a network feature comprises a storage unit for storing instructions and a processing circuit coupled to the storage unit. The processing circuit is configured to execute the instructions stored in the storage unit. The instructions comprise receiving system information indicating whether an Evolved Packet System (EPS) optimization is supported and a first Non Access Stratum (NAS) message indicating whether the EPS optimization is supported; determining to use the EPS optimization, when the system information indicates that the EPS optimization is not supported and the first NAS message indicates that the EPS optimization is supported; and determining not to use the EPS optimization, when the system information indicates that the EPS optimization is supported and the first NAS message indicates that the EPS optimization is not supported.

Abstract: A communication device for handling a Non-Access Stratum (NAS) procedure comprises instructions of transmitting a first session management (SM) message related to an access point name (APN) to a network; receiving a second SM message comprising a SM cause of insufficient resources and a back off timer value of a back off timer indicating that the back off timer is deactivated from the network in response to the transmission the first SM message; being forbidden to transmit a third SM message for the APN to the network, when the back off timer is deactivated for the APN; receiving a fourth SM message from the network indicating to deactivate and to reactivate an activated SM context associated with the APN, when the back off timer is deactivated for the APN; and transmitting a fifth SM message related to the APN to the network.

Abstract: A communication device of handling a paging procedure comprises instructions of transmitting a first Non Access Stratum (NAS) message comprising a first time interval for monitoring a paging occasion and a second time interval for monitoring the paging occasion to a network, wherein the second time interval is larger than the first time interval; receiving a second NAS message comprising a third time interval for monitoring the paging occasion from the network after transmitting the first NAS message, wherein the third time interval is larger than the first time interval; receiving a paging message from the network by using the third time interval, when a packet data network (PDN) connection for an emergency bearer service is not established or not establishing; and receiving the paging message from the network by using the first time interval, when the PDN connection for the emergency bearer service is established or establishing.

Abstract: A communication device of handling a detach procedure comprises a storage unit for storing instructions and a processing means coupled to the storage unit. The processing means is configured to execute the instructions stored in the storage unit. The instructions comprise attaching to a network in a Network Mode of Operation I (NMO I) for a circuit switched (CS) domain and a packet switched (PS) domain; transmitting a first General Packet Radio Service (GPRS) mobility management (GMM) message to the network; receiving a second GMM message comprising a GMM cause indicating an implicit detach from the network; and performing an International Mobile Subscriber Identity (IMSI) detach for the PS domain but not for the CS domain, when a Radio Resource (RR) connection exists.

Abstract: A communication device of handling a Non Access Stratum procedure comprises instructions of accessing a first network by using the first IMSI; transmitting a first NAS request message to the first network by using the first IMSI; receiving a NAS response message comprising a timer value and a cause value from the first network; starting a timer for the first IMSI with the timer value; not transmitting a second NAS request message to the first network by using the first IMSI, if the timer is running for the first IMSI; changing from the first IMSI to the second IMSI without removing the USIM; keeping the timer running, after changing to the second IMSI; accessing a second or the first network by using the second IMSI; and transmitting a third NAS request message to the second or the first network by using the second IMSI, when the timer is running.

Abstract: A communication device of handling a network feature comprises a storage unit for storing instructions and a processing circuit coupled to the storage unit. The processing circuit is configured to execute the instructions stored in the storage unit. The instructions comprise receiving system information indicating whether an Evolved Packet System (EPS) optimization is supported and a first Non Access Stratum (NAS) message indicating whether the EPS optimization is supported; determining to use the EPS optimization, when the system information indicates that the EPS optimization is not supported and the first NAS message indicates that the EPS optimization is supported; and determining not to use the EPS optimization, when the system information indicates that the EPS optimization is supported and the first NAS message indicates that the EPS optimization is not supported.

Abstract: A communication device of communicating with a network comprises instructions of establishing a plurality of bearer contexts with the network; initiating a data transmission associated with a first bearer context of the plurality of bearer contexts; transmitting a first Non Access stratum (NAS) request message comprising only a first bearer identity for the first bearer context to the network; receiving a first radio resource control (RRC) message configuring only a data radio bearer (DRB) for the first bearer context from the network, after transmitting the first NAS request message; transmitting a second NAS request message not comprising any bearer identity for the first bearer context to the network; and receiving a second RRC message configuring a plurality of DRBs for the plurality of bearer contexts from the network, after transmitting the second NAS request message.

Abstract: A communication device for handling a cell selection comprises a storage unit for storing instructions and a processing circuit coupled to the storage unit. The processing circuit is configured to execute the instructions stored in the storage unit. The instructions comprise receiving first system information from a first cell; determining whether the first cell supports a Cellular Internet of Thing (CIoT) feature according to the first system information; selecting a second cell which supports the CIoT feature according to second system information received from the second cell, if the first cell does not support the CIoT feature according to the first system information; and performing an attach procedure or a tracking area update procedure via the second cell.

Abstract: A communication device for handling a radio resource control (RRC) connection resume procedure comprises a storage unit for storing instructions and a processing circuit coupled to the storage unit. The processing circuit is configured to execute the instructions stored in the storage unit. The instructions comprise resuming a RRC connection suspended by a RRC message, when initiating a service request procedure; transmitting a first EXTENDED SERVICE REQUEST message comprising a service type information element (IE) to the network after the RRC connection is resumed, if the service request procedure is initiated for a packet switched (PS) service and the communication device is required to transmit an information element related to the PS service other than the service type IE.

Abstract: A communication device for handling a RRC connection comprises a storage unit and a processing circuit. The processing circuit is configured to execute instructions stored in the storage unit. The instructions comprise transmitting a first resume request message with a first resume identity for requesting a resume of the RRC connection to a first cell of a network; receiving a resume reject message from the first cell of the network; determining the first resume identity and at least one radio resource corresponding to the first resume identity are valid and keeping the first resume identity and the at least one radio resource, if the resume reject message comprises an indicator; and determining the first resume identity and the least one radio resource are invalid and releasing the first resume identity and the at least one radio resource, if the resume reject message does not comprise the indicator.

Abstract: A communication device for handling a Non-Access Stratum (NAS) procedure comprises instructions of transmitting a first session management (SM) message related to an access point name (APN) to a network; receiving a second SM message comprising a SM cause of insufficient resources and a back off timer value of a back off timer indicating that the back off timer is deactivated from the network in response to the transmission the first SM message; being forbidden to transmit a third SM message for the APN to the network, when the back off timer is deactivated for the APN; receiving a fourth SM message from the network indicating to deactivate and to reactivate an activated SM context associated with the APN, when the back off timer is deactivated for the APN; and transmitting a fifth SM message related to the APN to the network.

Abstract: A communication device of handling a paging procedure comprises instructions of transmitting a first Non Access Stratum (NAS) message comprising a first time interval for monitoring a paging occasion and a second time interval for monitoring the paging occasion to a network, wherein the second time interval is larger than the first time interval; receiving a second NAS message comprising a third time interval for monitoring the paging occasion from the network after transmitting the first NAS message, wherein the third time interval is larger than the first time interval; receiving a paging message from the network by using the third time interval, when a packet data network (PDN) connection for an emergency bearer service is not established or not establishing; and receiving the paging message from the network by using the first time interval, when the PDN connection for the emergency bearer service is established or establishing.

Abstract: A communication device of handling a Non Access Stratum procedure comprises instructions of accessing a first network by using the first IMSI; transmitting a first NAS request message to the first network by using the first IMSI; receiving a NAS response message comprising a timer value and a cause value from the first network; starting a timer for the first IMSI with the timer value; not transmitting a second NAS request message to the first network by using the first IMSI, if the timer is running for the first IMSI; changing from the first IMSI to the second IMSI without removing the USIM; keeping the timer running, after changing to the second IMSI; accessing a second or the first network by using the second IMSI; and transmitting a third NAS request message to the second or the first network by using the second IMSI, when the timer is running.

Abstract: A communication device for handling application specific congestion control comprises a storage unit for storing instructions and a processing circuit coupled to the storage unit. The processing circuit is configured to execute the instructions stored in the storage unit. The instructions comprise receiving information for barring an application category in a first cell of a first radio frequency of a registered public land mobile network (PLMN) from the registered PLMN; selecting a second cell of the registered PLMN, if a radio resource control (RRC) connection establishment procedure is not allowed for the application in the first cell of the first radio frequency; and performing the RRC connection establishment procedure to the second cell, if the RRC connection establishment procedure is allowed for the application in the second cell.

Abstract: A method for handling a service request procedure by a mobile communication device is provided. The method includes the steps of: starting a back-off timer associated with a service request procedure in response to the service request procedure for a normal service having been failed for a maximum number of retries, and initiating another service request procedure for an emergency bearer service before the back-off timer expires.

Abstract: A Packet Data Protocol (PDP) context handling method for a Mobile Station (MS) with a PDP context for an emergency bearer service is provided, wherein a radio access bearer (RAB) associated with the PDP context is released by a network. The method comprises the steps of: downgrading the maximum uplink bit rate and the maximum downlink bit rate associated with the PDP context from original non-zero positive values to a zero value; sending a request signal associated with a modification of the maximum uplink bit rate and the maximum downlink bit rate; and re-establishing the RAB for the PDP context with the maximum uplink bit rate and the maximum downlink bit rate reconfigured as the original non-zero values after the request signal has been sent.

Abstract: Methods for handling PS and CS voice services between a mobile communication device and a service network are provided. The method includes providing, by the service network, a first type of communication service to the mobile communication device and concurrently receiving, by the service network, a service request message to request for establishment of a second type of communication service, determining, by the service network, whether any type of communication service is an emergency service, and declining, by the service network, the type of communication service that is not the emergency service, wherein the service network only supports one type of communication service to the mobile communication device at one time.

Abstract: A communication device of handling a detach procedure comprises a storage unit for storing instructions and a processing means coupled to the storage unit. The processing means is configured to execute the instructions stored in the storage unit. The instructions comprise attaching to a network in a Network Mode of Operation I (NMO I) for a circuit switched (CS) domain and a packet switched (PS) domain; transmitting a first General Packet Radio Service (GPRS) mobility management (GMM) message to the network; receiving a second GMM message comprising a GMM cause indicating an implicit detach from the network; and performing an International Mobile Subscriber Identity (IMSI) detach for the PS domain but not for the CS domain, when a Radio Resource (RR) connection exists.

Abstract: A mobile communication device configured for Non Access Stratum (NAS) signaling low priority is provided. In the mobile communication device, a wireless module performs wireless transmissions and receptions to and from a service network, and a controller module originates an EXTENDED SERVICE REQUEST message for requesting emergency bearer services in an EMM IDLE mode. The controller module further transmits an RRC CONNECTION REQUEST message comprising an establishment cause indicating an emergency case to the service network via the wireless module in response to originating the EXTENDED SERVICE REQUEST message.