Relay device and voice communication recording method

A relay apparatus comprising:

• a communicator that communicates with a plurality of communication terminals that performs a voice communication;
• a communication session processor in which a call from a certain communication terminal calling the other at least one communication terminal allows the calling communication terminal and the called at least one communication terminal to be registered as participating terminals, a communication session identified based on session information is established, and transmission of a voice signal from any of the participating terminals in the established communication session allows the voice signal to be transmitted, together with the session information, to the other participating terminal in the same communication session;
• and
• a communication monitor that monitors the voice signal in the communication session,
• wherein
• the communication session processor notifies the communication monitor of information on the participating terminals in the communication session when the communication session is established,
• when the communication monitor is notified of information on a communication terminal in response to establishing the communication session, the communication monitor individually inputs and records the voice signal transmitted from the communication terminal so that the voice signal is distinguished from the voice signal from the other communication terminal, or the communication monitor records the voice signal transmitted to the communication terminal in the communication session,
• the communication terminal that is a target to be monitored, hereinafter referred to as a target terminal, is associated with a virtual device for individual monitoring, which is configured to monitor only the voice signal that is transmitted or received by the target terminal alone even when the communication session to which a plurality of the communication terminals including the target terminal participate is established, and
• the virtual device for individual monitoring is provided with a virtual device for upstream signal individual monitoring that is configured to monitor the voice signal transmitted from the target terminal, and
• a virtual device for downstream signal individual monitoring that is configured to monitor the voice signal transmitted to the target terminal,
• the virtual device for upstream signal individual monitoring is associated with an input buffer in which the voice signal transmitted from the target terminal, of which the voice signal is recorded, is buffered, and
• the virtual device for downstream signal individual monitoring is associated with an output buffer in which the voice signal transmitted to the target terminal is buffered,
• when the communication monitor is notified of information on the target terminal in response to establishing the communication session,
• the communication monitor establishes a virtual communication session to which only the target terminal and the virtual device for individual monitoring are allowed to participate, and
• the communication monitor records the voice signal transmitted to the virtual device for individual monitoring in the virtual communication session.