A system is presented that includes secure push-to-talk voice functionality. Using encryption, authentication, user filtering, and integration with new and existing LMR systems, a secure voice platform ensures malicious software, unauthorized access and brute force security attacks will not compromise the voice communications of the system. The VoIP system is engineered to ensure graceful system degradation in the event of maintenance activities, natural disasters and failure modes. The hardened VoIP system offers the functions a LMR trunking system while utilizing broadband connections. Private calls, group calls, Emergency Alarms with covert monitoring capability, scanning and priority scanning may be incorporated into the system. The system includes a VoIP-controller that serves as a trunking controller, manages available VoIP-based conference bridges, and assigns them as needed to the parties involved in each voice call. The system includes multiple fallback methods that may be prioritized based on pre-failure analytics.

A method, a mission critical (MC) server, and a receiver for managing media communication in an MC system are provided. The method comprises receiving, from a sender, a request and a media stream for transmitting the media stream to one or more receivers. The request indicates a mode of transmission of the media stream. Further, the method comprises transmitting a notification message indicating a mode of reception identified based on the mode of transmission, to the one or more receivers for receiving the media stream from the sender. The mode of reception is one from among an emergency mode and a normal mode. Thereafter, the method comprises transmitting the media stream to the one or more receivers subsequent to transmission of the notification message, when the mode of reception is the emergency mode.

The present disclosure relates to a technology for a sensor network, machine to machine (M2M) communication, machine type communication (MTC), and Internet of things (IoT). The present disclosure may be utilized for an intelligent service (smart home, smart building, smart city, smart car or connected car, health care, digital education, retail business, security and a safety-related service, etc.) on the basis of the technology. A method for providing a push-to-talk (PTT) service in a communication system, which is proposed by an embodiment of the present disclosure, comprises the steps of: generating a file format including information associated with time points at which multiple pieces of data should be reproduced; and reproducing the multiple pieces of data on the basis of the file format.

A spatial information delivery system according to an embodiment of the present invention includes a partial spatial information generation device, and a plurality of partial spatial information transmission devices existing within a facility. The partial spatial information generation device generates partial spatial information which is part of spatial information relating to the facility and which is specific to each of the partial spatial information transmission devices, for each of the partial spatial information transmission devices based on locations of the partial spatial information transmission devices. Each of the partial spatial information transmission devices transmits the partial spatial information corresponding to the own partial spatial information transmission device.

A media downlink transmission control method and a related device, the method including receiving a remote media reception message sent by an authorized terminal, where the remote media reception message includes a target user identifier, determining a first target media stream based on the remote media reception message, and sending the first target media stream to a destination terminal corresponding to the target user identifier.

A method is provided that allows for prioritizing Push-To-Talk (PTT) service in a roamed network. PTT service is enabled for a mobile device at a first network. The mobile device roams to a second network that is of an older generation than the first network. It is determined that the mobile device has an active PTT subscription. PTT service is prioritized for the mobile device over circuit switched services on the second network.

The present disclosure relates to a communication method and system for converging a 5.sup.th-Generation (5G) communication system for supporting higher data rates beyond a 4.sup.th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The method includes transmitting a service authorization request message to a first network device, the first network drive including a proximity-based service (ProSe) function, and receiving a service authorization response message from the first network device. The first terminal is a relay terminal capable of performing a UE-to-network relay function.

A method and device for performing push-to-talk and text communications. The device includes a display and an electronic processor communicatively coupled to the display. The electronic processor is configured to generate a graphical user interface, generate, on the display, a first push-to-talk button having a first dimension and located proximate to a conversation thread window including a historical view portion and a new-entry portion, and receive, on the display, a first user input selecting the new-entry portion. The electronic processor is further configured to generate on the display, in response to receiving the first user input, a text-entry portion, replace, in response to receiving the first user input, the first push-to-talk button with a second push-to-talk button at a same or different first location, receive, via the display, a second user input selecting the text-entry portion, and alter, in response to the second user input, the second push-to-talk button.

According to one embodiment, a signal processing apparatus includes processing circuitry. The processing circuitry correlates a plurality of communication terminals as a group. The processing circuitry assigns a first transmission right to one of the communication terminals in the group and a second transmission right to one of the communication terminals in the group. The processing circuitry transmits, through a first channel, image data transmitted from the communication terminal which is assigned with the first transmission right to the other communication terminals in the group. The processing circuitry transmits, through a second channel, voice data transmitted from the communication terminal which is assigned with the second transmission right to the other communication terminals in the group. The processing circuitry is configured to permit a single communication terminal to be assigned with both the first and second transmission rights.

According to various aspects, exemplary embodiments are disclosed of systems, methods and devices related to operator control unit base VOIP communication. In an exemplary embodiment, an operator control unit based VOIP communication system includes an operator control unit in wireless communication with a locomotive control unit coupled to a locomotive to control operation of the locomotive. The operator control unit includes a first wireless interface to transmit one or more commands to the locomotive control unit, and an auxiliary wireless interface. The system also includes a microphone in communication with the operator control unit. The operator control unit is configured to receive voice signals from the microphone, and to transmit voice data corresponding to the received voice signals via the auxiliary wireless interface. The voice data is transmitted by the auxiliary wireless interface though a railyard infrastructure wireless network using a voice over internet protocol (VOIP).