Page 35 - ITU-T Focus Group IMT-2020 Deliverables

ITU-T Focus Group IMT-2020 Deliverables 2

9.14 Interworking

9.14.1 Description
As new IMT-2020 network doesn’t get better coverage than existing LTE network in preliminary stage, LTE
network is still needed to guarantee services when UE leaves out of IMT-2020 coverage to existing LTE
network coverage as shown in figure1. So IMT-2020 core network is required to support interworking with
existing LTE network, and including as an anchor to manage handover action between IMT-2020 and existing
LTE network.

Existing LTE
IMT-2020
Network
Interworking

Core Network EPC

IMT-2020 AN LTE

UE UE

Figure 1 – Interworking scenario

9.14.2 Requirements
[REQ] The network architecture for IMT-2020 is required to support interworking with existing LTE network.

[REQ] The network architecture for IMT-2020 is required to support mobility management, session
management and service continuity as an anchor when handover from IMT-2020 to existing LTE network.
[REQ] The network architecture for IMT-2020 is required to support end-to-end QoS management, charging
control when interworking between IMT-2020 and existing LTE network.

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