Correlation system involving inter change between different types of radio bearers

A core network node packet data (10) it is supporting communication of packet data in a first core network comprising first communication means (1) for managing control plane and management of mobility and second means for communication (2) for managing user plane and means for communication with a mobile dual mode terminal on a first radio network, wherein the core network node packet data (10) comprises or communicates with a correlation function ( 3) for correlation between a first radio bearers used in the first core network and a second radio bearers of a different type of type of the first radio bearers and used in a second central network handovers of mobile terminals dual mode from the first network Central to the second central network or vice versa, and wherein the first communication means (1) are adapted to, upon receipt of a control message from a second n odo core network requesting carriers or contexts carrier through or via the second media enabled the correlation function for correlating a first carriers used in the first central radio network to a second carrier used in the second network central radio or vice versa using information in a mapping repository provided in said correlation function, to activate the correlation means a change in inter system, ISC, or a handover initiated by the mobile terminal; characterized in that the central network node packet data (10) is a Node Evolved Packet Core, EPC, adapted to operate in a network of SAE / LTE and wherein the correlation function comprises a first repository (31) for maintaining the correlation information carrier for correlating a first carrier on second carrier and a second repository (32) for maintaining the correlation information carrier for correlating a second carriers on a first carrier and wherein the first and second repositories correlation comprise a first and a second table of predefined correlation respectively, the first mapping table comprising rules for mapping labels SAE / LTE QoS or traffic classes 2G / 3G and second correlation table which it comprises rules for mapping QoS traffic classes or 2G / 3G labels SAE / LTE.