Portal server connects with a plurality of content supply servers and is also connectable with a client terminal via a communication network. Each of the plurality of content supply servers has music content. The portal server is accessed by the client terminal, and the portal server transmits, to the client terminal, a list of music content suppliable by the content supply servers, in response to a request from the client terminal. Desired music content can be selected in the client terminal on the basis of the list transmitted by the portal server, and selection information specifying the selected music content can be transmitted from the client terminal to the communication network. Then, in response to the selection information, the selected music content can be supplied from the content supply server having the selected music content.