Can you answer this question:
Which LTE network node is responisble for allocating IP address to a sepcific terminal?
The PDN-GW normally assigns IP addresses. Also possible to have a static address in the user profile, or have DHCP server assign the address though both of these are quite rare.
UE IP allocation can be done in three ways
1. Static IP - configured in HSS as part of Subscritpion Profile/
2. PGW Local UE Pools
3. Deferred IP Allocation using DHCP