Abstract: A method and an apparatus for transmitting a group message in a unicast-based network are provided. A method of a terminal for transmitting a group message in a unicast-based network includes when receiving a session connection request message, transmitting a first group notification message for forming a relay group, to other terminals, receiving a second group notification message from at least one other terminal, forming a relay group with the terminal and at least one other terminal corresponding to the second received group notification message, and determining one of the terminals of the relay group as a relay terminal which relays the group message to other terminals in the relay group.

Abstract: A Voice over Internet Protocol (VoIP) terminal has a Quality of Service (QoS) monitoring function and uses a QoS monitoring method. In a VoIP system performing real-time voice communication over an IP network, a packet loss value and a time-axis index value are detected, and are calculated from a real-time transport protocol (RTP) packet and an RTP control protocol (RTCP) packet, a QoS state value of the network is obtained in real time, the detected QoS state value is compared to a preset QoS state table, and thus a QoS state of the IP network is displayed for users.

Abstract: Exemplary embodiments of the invention provide a system and method for providing multicast service in a unicast-based Voice over Internet Protocol (VoIP) system. The system and method include a VoIP call server receiving subnet information from VoIP terminals authenticated by an authentication server, generating multicast group information, and providing the multicast group information to the respective authenticated VoIP terminals. The VoIP call server searches a list of grouped VoIP terminals, selects a VoIP terminal of a corresponding subnet, transmits multicast session information to the selected VoIP terminal to set the VoIP terminal as a relay VoIP terminal, and requests a media server to transmit group message data to the relay VoIP terminal. According to this system and method, it is possible to implement a multicast service in a unicast-based VoIP system without adding additional equipment.

Abstract: A method and an apparatus for transmitting a group message in a unicast-based network are provided. A method of a terminal for transmitting a group message in a unicast-based network includes when receiving a session connection request message, transmitting a first group notification message for forming a relay group, to other terminals, receiving a second group notification message from at least one other terminal, forming a relay group with the terminal and at least one other terminal corresponding to the second received group notification message, and determining one of the terminals of the relay group as a relay terminal which relays the group message to other terminals in the relay group.

Abstract: In a system and method for processing multicast in a unicast-based Voice over Internet Protocol (VoIP) system, the method includes the steps of: receiving, at a VoIP call server, subnet information from VoIP terminals authenticated by an authentication server, generating multicast group information, and then providing the multicast group information to the respective authenticated VoIP terminals; searching, at the VoIP call server, a list of grouped VoIP terminals, selecting a VoIP terminal of a corresponding subnet, and then transmitting multicast session information to the selected VoIP terminal so as to set the VoIP terminal as a relay VoIP terminal; and requesting, at the VoIP call server, a media server to transmit group message data to the relay VoIP terminal. According to the system and method, it is possible to implement multicast in a unicast-based VoIP system without the need for additional equipment.

Abstract: A Voice over Internet Protocol (VoIP) terminal has a Quality of Service (QoS) monitoring function and uses a QoS monitoring method. In a VoIP system performing real-time voice communication over an IP network, a packet loss value and a time-axis index value are detected, and are calculated from a real-time transport protocol (RTP) packet and an RTP control protocol (RTCP) packet, a QoS state value of the network is obtained in real time, the detected QoS state value is compared to a preset QoS state table, and thus a QoS state of the IP network is displayed for users.