Patent ID: 8438605

Claim:
A video distribution system comprising a user terminal, a bandwidth controller, an SIP session controller, and a video distribution server which are interconnected through an IP network, wherein: said user terminal sends a session establishing request for securing a session, according to an SIP with the video distribution server, to said SIP session controller, based on content information including information for the user terminal to establish a session with the video distribution server; when said SIP session controller receives said session establishing request, said SIP session controller establishes a session between said user terminal and said video distribution server, and makes a first bandwidth securing request for requesting said bandwidth controller to reserve a first bandwidth for the distribution of video content in a communication path between said user terminal and said video distribution server; when said bandwidth controller receives said first bandwidth securing request, said bandwidth controller secures the first bandwidth for the distribution of video content in the communication path between said user terminal and said video distribution server; said user terminal or said video distribution server makes a second bandwidth changing request for requesting said SIP session controller to change the first bandwidth for the distribution of video content to match a second bandwidth that is required for distributing video content; when said SIP session controller receives said second bandwidth changing request, said SIP session controller makes a third bandwidth changing request for requesting said bandwidth controller to change the first bandwidth for distribution of video content which is secured in the communication path between said user terminal and said video distribution server to the second bandwidth that is required for distributing video content; and when said bandwidth controller receives said third bandwidth changing request, said bandwidth controller changes the first bandwidth which is secured in the communication path between said user terminal and said video distribution server to the second bandwidth that is required for distributing video content.