User Data Convergence – UDC – supports a layered architecture that separates the user data from the application logic, so that user data is stored in a logically unique repository – UDR – allowing access from the core and Service Layer entities, hereby named Application Front Ends.
UDC supports a Front End and a Backend that allows different databases: HLR, HSS, AUC, EIR, AAA, MNP, etc.. to be integrated.
Where appropriate, data (e.g. from HLR, HSS, etc..) can be sent to the VLR.
Your management paper should look beyond HLR and EIR. Look at 4G and 5G.