PROTECTION AGAINST UNSOLICITED COMMUNICATION FOR INTERNET PROTOCOL MULTIMEDIA SUBSYSTEM

摘要

A PUCI system is designed to process an incoming call originated by the user equipment toward the counterpart user equipment via an EMS node having a PUCI-light functionality, which includes an IBCF/I-CSCF, a S-CSCF, and a database storing the PUCI-light information. Through a query to the database indicating a suspicious session in relation to the incoming call, the IMS node immediately blocks the suspicious session or simply marks the suspicious session for the further processing at a subsequent node. The reason for rejection is included in a SIP BYE/ERROR message of an original session setup message, which is interpreted by a previous IMS node so as to obtain the relevant information from a SIP header. The relevant information is stored in either a global operator policy database or a local database, thus enabling a PUCI-negating IMS node to reject an unsolicited call related to the blocked session.