A method for identifying an Internet Protocol, IPv6, session, comprising: performing, by a user equipment, UE, an Extensible Authentication Protocol, EAP, authentication with an authentication server via a network gateway; wherein when the EAP authentication of the UE is successful, an EAP success message is sent to the UE by the authentication server via the network gateway; after the EAP authentication, starting Dynamic Host Configuration Protocol Prefix Delegation, DHCP PD, and generating a DHCP Transaction ID by the UE; requesting, by the UE, an IPv6 address prefix through the DHCP PD, wherein during the IPv6 address prefix PD process the DHCP Transaction ID remains unchanged; wherein when the IPv6 address prefix PD is successful, the DHCP server sends an IPv6 address prefix to the UE with a DHCP reply message; setting the IPv6 address prefix by the UE and the network gateway delegated by the DCHP replay message as a IPv6 session ID; wherein a IPv6 session represents a network access connection session associated with an IPv6 address of the UE; and filtering, at the network gateway, a received IPv6 session packet from the UE according to the IPv6 session ID (step 407); wherein the filtering the received IPv6 session packet from the UE according to the IPv6 session ID comprises: determining whether the IPv6 session ID and an access port of the UE are consistent with a preset binding relation table; if the IPv6 session ID and the access port of the UE are consistent with the preset binding relation table, permitting the IPv6 session packet to pass; if the IPv6 session ID and the access port of the UE are not consistent with the preset binding relation table, discarding the IPv6 session packet. performing, by a user equipment, UE, an Extensible Authentication Protocol, EAP, authentication with an authentication server via a network gateway; wherein when the EAP authentication of the UE is successful, an EAP success message is sent to the UE by the authentication server via the network gateway; after the EAP authentication, starting Dynamic Host Configuration Protocol Prefix Delegation, DHCP PD, and generating a DHCP Transaction ID by the UE; requesting, by the UE, an IPv6 address prefix through the DHCP PD, wherein during the IPv6 address prefix PD process the DHCP Transaction ID remains unchanged; wherein when the IPv6 address prefix PD is successful, the DHCP server sends an IPv6 address prefix to the UE with a DHCP reply message; setting the IPv6 address prefix by the UE and the network gateway delegated by the DCHP replay message as a IPv6 session ID; wherein a IPv6 session represents a network access connection session associated with an IPv6 address of the UE; and filtering, at the network gateway, a received IPv6 session packet from the UE according to the IPv6 session ID (step 407); wherein the filtering the received IPv6 session packet from the UE according to the IPv6 session ID comprises: determining whether the IPv6 session ID and an access port of the UE are consistent with a preset binding relation table; if the IPv6 session ID and the access port of the UE are consistent with the preset binding relation table, permitting the IPv6 session packet to pass; if the IPv6 session ID and the access port of the UE are not consistent with the preset binding relation table, discarding the IPv6 session packet. determining whether the IPv6 session ID and an access port of the UE are consistent with a preset binding relation table; if the IPv6 session ID and the access port of the UE are consistent with the preset binding relation table, permitting the IPv6 session packet to pass; if the IPv6 session ID and the access port of the UE are not consistent with the preset binding relation table, discarding the IPv6 session packet.