Patent attributes
Provided are a stream distribution system and a failure detection method capable of easily identifying the cause of quality loss in stream distribution. This stream distribution system includes a first server for communicating with a client terminal via a router and sending stream data, and a second server configured as a redundant server of the first server and connected to the first server. The first server has a communication status notification unit for sending a connection management table concerning the communication with the client terminal to the second server. The second server has a packet recording unit for acquiring a mirror packet, which is a copy of a packet sent to the first server, from the router, and a network failure monitoring unit for detecting a failure in a network between the first server and the client terminal based on the connection management table and a packet buffer.