A train control system enabling a train to smoothly travel while performing handover. The system includes an on-vehicle wireless station mounted on a train following a preceding train and connected to an on-vehicle control device of the train, ground wireless base stations capable of wirelessly communicating with the on-vehicle wireless station, and a base station control device to control the base stations. The ground wireless base station is located between the ground wireless base station with which the on-vehicle wireless station is communicating and the ground wireless base station forming a communication area including a travelling permission point determined by a position of the train. The base station control device reserves radio resources of the ground wireless base stations while communicating with the ground wireless base station.

An example system includes a server communicatively connected to a cellular base transceiver station having an RF coverage area and configured for RF communication with a first entity that is a transceiver device in the RF coverage area, wherein the server comprises a first publish-subscribe broker that is part of a publish-subscribe broker network that comprises one or more publish-subscribe brokers, wherein a second entity connected to any of the one or more publish-subscribe brokers in the publish-subscribe broker network accepts communications from the transceiver device if the second entity subscribes to data packets published by the transceiver device, and wherein the data packets published by the transceiver device are routed through the publish-subscribe broker to which the second entity is connected.

An example system includes a server communicatively connected to a cellular base transceiver station having an RF coverage area and configured for RF communication with a first entity that is a transceiver device in the RF coverage area, wherein the server comprises a first publish-subscribe broker that is part of a publish-subscribe broker network that comprises one or more publish-subscribe brokers, wherein a second entity connected to any of the one or more publish-subscribe brokers in the publish-subscribe broker network accepts communications from the transceiver device if the second entity subscribes to data packets published by the transceiver device, and wherein the data packets published by the transceiver device are routed through the publish-subscribe broker to which the second entity is connected.

Certain aspects of the present disclosure are directed to a method for wireless communication. The method generally includes receiving a message for dual-active-protocol stack (DAPs) handover (HO) from a source network entity to a target network entity, wherein carrier-aggregation (CA) is configured with the source network entity prior to reception of the message for HO, deactivating the CA in response to reception of the message for handover (HO) to activate a single carrier mode with the source network entity, and performing the HO from the source network entity to the target network entity during a HO period, wherein the single carrier mode is maintained with the source network entity during at least a portion of the HO period, and wherein connection with the target network entity is maintained during the at least the portion of the HO period.

Aspects of the present disclosure propose solutions to a problem of mobility interruption during handover between base stations by providing a UE with mechanisms to report the UE capability for simultaneous connectivity based handover, or so-called Dual Active Protocol Stack Handover (DAPS-HO). A UE reports the DAPS-HO capability of the UE to the network and then the base station initiates physical layer procedures to carry out DAPS-HO in accordance with the DAPS-HO capability reported by the UE. Aspects of the present disclosure also provide examples of signaling that may be used by the UE for reporting DAPS-HO capability to the network and the physical layer procedures that the UE may follow in accordance with the configuration that the network provides to the UE, which should be in accordance with the UE's capability.

According to a communication method and a communications apparatus, in a process in which an access network device serving a terminal is handed over from a source access network device to a target access network device, a user plane function network element may transmit first information to the source access network device. The first information is used to indicate that the user plane function network element bicasts downlink packets to the source access network device and the target access network device, so that after determining that a data packet received before the first information is sent to the terminal, the source access network device triggers an air interface handover, to avoid a packet loss in a handover process, or so that the source access network device synchronizes a PDCP SN of the source access network device with a PDCP SN of the target access network device.

The present invention relates to a method of processing packets by a user equipment (UE) in a wireless communication system, wherein a Packet Data Convergence Protocol (PDCP) entity of the UE has a first decompression function for a first network and a second decompression function for a second network. Especially, the method comprises receiving a first packet from the first network; delivering the first packet to an upper layer after decompressing the first packet using the first decompression function; connecting the second network with maintaining a connection of the first network; receiving the first packet and a second packet from the second network; discarding the first packet after decompressing the first packet using the second decompression function; and delivering the second packet to the upper layer after decompressing the second packet using the second decompression function.

The present invention relates to a method of processing packets by a user equipment (UE) in a wireless communication system, wherein a Packet Data Convergence Protocol (PDCP) entity of the UE has a first decompression function for a first network and a second decompression function for a second network. Especially, the method comprises receiving a first packet from the first network; delivering the first packet to an upper layer after decompressing the first packet using the first decompression function; connecting the second network with maintaining a connection of the first network; receiving the first packet and a second packet from the second network; discarding the first packet after decompressing the first packet using the second decompression function; and delivering the second packet to the upper layer after decompressing the second packet using the second decompression function.

A data transmission method and apparatus. The method includes: a source access network device that receives an end marker from a core network device through a transmission tunnel of a PDU session of a first terminal device, where the PDU session is associated with a first multicast/broadcast service; and in response to the end marker, the source access network device determines, based on the association between the PDU session and the first multicast/broadcast service, that the end marker acts on the first multicast/broadcast service of the first terminal device, to stop sending data of the first multicast/broadcast service to a target access network device through a forwarding tunnel of the first terminal device.

A data transmission method and apparatus. The method includes: a source access network device that receives an end marker from a core network device through a transmission tunnel of a PDU session of a first terminal device, where the PDU session is associated with a first multicast/broadcast service; and in response to the end marker, the source access network device determines, based on the association between the PDU session and the first multicast/broadcast service, that the end marker acts on the first multicast/broadcast service of the first terminal device, to stop sending data of the first multicast/broadcast service to a target access network device through a forwarding tunnel of the first terminal device.