ity also selects the target MME entity when the mobile changes both cell and group (pool). The MME entity provides the information required for lawful interception, such as the mobile status (idle or connected), the TAI location area if the mobile is idle or the E-UTRAN Cell Global Identifier (ECGI) if the mobile is in session. 1.1.1.3. SGW entity The SGW entities are organized into groups (pools). To ensure load balancing of SGW entities, each eNB entity within a group must have access to each SGW entity of the same group. The SGW entity forwards incoming data from the PGW entity to the eNB entity and outgoing data from the eNB entity to the PGW entity. When the SGW entity receives data from the eNB or PGW entities, it refers to the QCI identifier for the implementation of the data scheduling mechanism. The SGW entity can perform marking of the DSCP field of IP header based on the assigned QCI identifier for incoming and outgoing data. The SGW entity is the anchor point for intra-system handover (mobility within EPS network) provided that the mobile does not change group. Otherwise, the PGW entity performs this function. The SGW entity is also the anchor point at the inter-system handover PS-PS, requiring the transfer of traffic data from the mobile to the second or third generation mobile network. The SGW entity informs the MME entity of incoming data when the mobile is in idle state, which allows the MME entity to trigger paging of all eNB entities of the TAI location area. Network Architecture A mobile in the idle state remains attached to the MME entity. However, it is no longer connected to the eNB entity and thus the radio bearer and the S1 bearer are deactivated. 1.1.1.4. PGW entity The PGW entity is the gateway router providing the EPS network connection to the PDN network. When the PGW entity receives data from the SGW entity or PDN network, it refers to the QCI identifier for the implementation of the data scheduling mechanism. The PGW entity can perform DSCP marking of IP header based on the assigned 