Abstract: Provided is a network camera including a processor and a memory storing instructions executable by the processor, the processor executing the instructions to perform: an operation of capturing a video using an imaging device; an operation of publishing a topic related to the captured video to a message broker; an operation of receiving a search request message regarding the published topic from the message broker; an operation of searching the stored video according to the search request message; and an operation of generating a response message regarding the search request message based on the search result and sending the response message to the message broker.

Abstract: A media stream playing apparatus for receiving a media stream transmitted from a media service unit and playing the media stream on a web browser is provided. The media stream playing apparatus includes a transmission module configured to establish a communication connection at a transport layer level with the media service unit, a websocket module configured to establish a websocket connection with the media service unit via a handshake procedure based on the communication connection and transmit or receive websocket packets to or from the media service unit while maintaining the websocket connection, a streaming module configured to receive Real-time Transport Protocol (RTP) packets carried by the websocket packets, a media decoder configured to decode the media stream obtained from the RTP packets to reconstruct video, and an output device configured to display the reconstructed video on a screen by embedding the reconstructed video in the web browser.

Abstract: Provided are an authentication system and a method of operating the authentication system. The authentication system allows network cameras to authenticate an image storage device as a client. The authentication system includes an authentication preprocessing unit provided in the client to calculate and store an offset time representing a difference between time information of the client and time information that is received from a network camera in response to a time information request to the network camera, and an authentication processing unit provided in the network camera to authenticate the client by receiving authentication information including the offset time from the client in response to an authentication request of the client.

Abstract: A media stream playing apparatus for receiving a media stream transmitted from a media service unit and playing the media stream on a web browser is provided. The media stream playing apparatus includes a transmission module configured to establish a communication connection at a transport layer level with the media service unit, a websocket module configured to establish a websocket connection with the media service unit via a handshake procedure based on the communication connection and transmit or receive websocket packets to or from the media service unit while maintaining the websocket connection, a streaming module configured to receive Real-time Transport Protocol (RTP) packets carried by the websocket packets, a media decoder configured to decode the media stream obtained from the RTP packets to reconstruct video, and an output device configured to display the reconstructed video on a screen by embedding the reconstructed video in the web browser.

Abstract: Provided are an authentication system and a method of operating the authentication system. The authentication system allows network cameras to authenticate an image storage device as a client. The authentication system includes an authentication preprocessing unit provided in the client to calculate and store an offset time representing a difference between time information of the client and time information that is received from a network camera in response to a time information request to the network camera, and an authentication processing unit provided in the network camera to authenticate the client by receiving authentication information including the offset time from the client in response to an authentication request of the client.