PURPOSE : A transaction information post office for automatically delivering the realty information based on the personal information protection of an information receiver is provided to receive the realty information of an information sender and to deliver it to the information receiver in real-time through the transaction information post office.CONSTITUTION : The information sender receives a member ID and a password through a member registration process, and receives a URL(Uniform Resource Locator) and the contents of a parameter of the realty information registration program for registering the link. The information sender makes the realty information received from the post office automatically by inserting the URL and the parameter into the realty registration program. The information receiver receives the realty information by directly visiting the post office. The post office gives a reception number to the realty information and stores it in a realty information table. The post office extracts the reception numbers of the information receiver matched with the reception number of the received realty information. The post office delivers the realty information to the extracted information receivers.? KIPO 2004