Embodiments of this application provide a network handover method and a related device. The method includes: when receiving a user terminal handover request that is sent by a source radio access network node and that carries a target base station identifier, determining, by a source mobility management function entity based on the target base station identifier, to trigger inter-RAT network handover; sending a first message to a source session management function entity; receiving a second message sent by the source session management function entity, where the second message includes a session management context; and sending a relocation request to a target mobility management function entity, where the relocation request is used to instruct the target mobility management function entity to perform inter-RAT network handover on the user terminal. In this way, data continuity in an inter-RAT network handover process is ensured.

Apparatuses, methods, and systems are disclosed for establishing an IP multimedia subsystem session. One method includes receiving, at a first network entity from a user device, a first session initiation protocol message comprising a session description protocol, wherein the first session initiation protocol message is used to establish an internet protocol multimedia subsystem session for an application. The method includes transmitting, from the first network entity to a second network entity, a first message comprising an internet protocol address and an identifier for the application. The method includes receiving, at the first network entity from the second network entity, a status of a radio access technology of the user device, wherein the status of the radio access technology of the user device is received by the second network entity from a third network entity.

A device may receive relationship information indicating a relationship between first geographic information and a network gateway. The network gateway may be associated with providing a user device with access to a network. The device may store the relationship information. The device may receive, from the user device and via a base station, second geographic information indicating a tracking area in which the user device is located. The device may identify one or more network gateways, associated with the second geographic information, based on the second geographic information and the relationship information. The device may provide, to the user device, one or more device identifiers associated with the one or more network gateways to permit the user device to access the network via the one or more network gateways. The one or more device identifiers may be provided in association with a non-access stratum message.

The disclosure includes a method for rapidly recovering the speed of TCP transmission after a cross technology handover experienced by a mobile device. In the method, the mobile device receives a sequentially first TCP data packet after the cross technology handover completes via a TCP session between the mobile device and a remote TCP server, generates a first acknowledgement (ACK) associated with the sequentially first TCP data packet, where the first ACK comprises a first Selective ACK (SACK) option, removes the first SACK option from the first ACK when a gap exists between data in the sequentially first TCP data packet and data received before the cross technology handover occurs, and sends the first ACK without the first SACK option to the remote TCP server via the TCP session. Because the ACK is without the SACK option when the gap exists, the speed of TCP transmission will be recovered rapidly.

A technique is disclosed to minimize service interruption at a wireless user equipment device during a handover by maintaining dual active connections during the handover. Upon initiating the handover, an initial/first connection with a first access node is maintained while establishing a second connection with a second access node. The user equipment device can receive data over the first connection and second connection during the handover. The first connection may be terminated (by the user equipment device or by timing out due to inactivity) after the handover is completed. Other aspects, embodiments, and features are also claimed and described.

Device Assisted Services (DAS) for protecting network capacity is provided. In some embodiments, DAS for protecting network capacity includes monitoring a network service usage activity of the communications device in network communication; classifying the network service usage activity for differential network access control for protecting network capacity; and associating the network service usage activity with a network service usage control policy based on a classification of the network service usage activity to facilitate differential network access control for protecting network capacity.

Techniques are provided for adaptively changing a periodicity of measuring signal characteristics for a UE in a relatively high speed environment based on one or more signal characteristics being outside of a threshold. Periodicity of measuring signal characteristics may be made directly by changing an interval at which measurements are taken. In certain examples, periodicity of measuring signal characteristics may be made indirectly by changing the length of a discontinuous reception (DRX) cycle. Some techniques provide one or more radio link monitoring (RLM) parameters may be modified based on a determination that a UE is in a high speed environment or measured signal characteristics are outside of a threshold.

A network assignment method of a gateway in a wireless communication system including a first communication network and a second communication network is provided. The method includes receiving, when a terminal is connected to the first communication network, a create session request message from a second mobility management entity associated with a second base station operating the second communication network, allocating second attach information for establishing a bearer between the gateway and the second base station based on first attach information generated for connection to the first communication network, and transmitting a create session response message including the second attach information to the second mobility management entity in response to the create session request message.

A base station (1) is connectable to a mobile station (4) by a plurality of Radio Access Technologies (RATs) including first and second RATs. The base station (1) is configured to be able to use a communication path (400) that passes through a first upstream network (140) corresponding to the first RAT, when the mobile station (4) performs communication via the second RAT. This enables, for example, efficient use of the upstream networks when the Multi-RAT base station (1) supports a plurality of upstream networks.

Methods, systems, and devices for wireless communication are described. A user equipment (UE) may prevent rejected attachment requests when connecting to a trusted wireless local area network (WLAN) and from a wireless wide area network (WWAN). For example, an attachment packet data network (PDN) connection may be maintained with the WWAN while connected to the trusted WLAN. In some cases, the connection used to maintain the attachment may be an internet protocol (IP) multimedia subsystem (IMS) connection. Alternatively, the UE may determine that the WLAN connection is a trusted connection and deactivate the WWAN connection. Should the WLAN become unavailable the UE may reactivate the connection with the WWAN.