In order to prevent multiple nodes from requesting data from the network at the same time, a large amount of signaling is caused to cause the occurrence of “signalling flood”. The Hiibook product's design architecture uses SN (Structural Network) design, and the email network node is linked through a specific IMAP/SMTP protocol. Together, through the protocol, Hiibook can ensure that any node can efficiently find any data needed at other nodes, even if it is rarely seen.