Description:AS FILED PDF DOCUMENTS , Claims:AS FILED PDF DOCUMENTS

WE CLAIMS:
1. A communication terminal apparatus configured to connect to a plurality of networks,
the plurality of networks comprising: a first network including a User Plane Function
(UPF); and a second network including a Non-3GPP Interworking Function (N3IWF),
wherein
the communication terminal apparatus is configured to connect to the first
network, and connect to the second network through the UPF in the first network and
the N3IWF in the second network, and
the communication terminal apparatus is configured to establish a connection
to the N3IWF after establishing a connection to the first network.
2. The communication terminal apparatus according to claim 1, wherein the first
network includes an Access and Mobility Management Function (AMF), and
the communication terminal apparatus is configured to transmit information on
Qualify of Service (QoS) in the first network to the AMF.
3. The communication terminal apparatus according to claim 2, wherein the
communication terminal apparatus is configured to transmit the information on QoS to
the AMF in a Protocol Data Unit (PDU) session modification procedure.
4. The communication terminal apparatus according to claim 1, wherein a connection of
the communication terminal apparatus to the second network through the first network
is controlled based on information indicating a relationship between information on
Qualify of Service (QoS) in the first network and information on QoS in the second
network.
5. The communication terminal apparatus according to claim 1, wherein the
communication terminal apparatus is configured to establish an Access Network (AN)
connection in the second network with the N3IWF.
6. The communication terminal apparatus according to claim 5, wherein the second
network includes an Access and Mobility Management Function (AMF), and
the N3IWF is configured to transmit information on release of the AN
connection to the AMF.
7. The communication terminal apparatus according to claim 6, wherein the second
network further includes a Session Management Function (SMF), and
the AMF is configured to transmit, to the SMF, information on deactivation of
a user plane connection in a Protocol Data Unit (PDU) session between the
communication terminal apparatus and the second network.

8. The communication terminal apparatus according to claim 1, wherein the
communication terminal apparatus is configured to initiate release of Internet Protocol
Security (IPsec) configuration.
9. The communication terminal apparatus according to claim 1, wherein the
communication terminal apparatus has a Connection Management (CM) state in the first
network and a CM state in the second network, independently.
10. The communication terminal apparatus according to claim 1, wherein the
communication terminal apparatus has a Registration Management (RM) state in the
first network and an RM state in the second network, independently.