1. Design and construction of a flexible and expandable model of the ATM based fixed part of UMTS for performance assessment of signalling and user data transfer protocols based on OPNET Nikolaos Frangiadakis Department of Informatics, University of Athens

2. UMTS Environment GATE SWHLR

3. UMTS Environment GATESW HLR

4. Mobility Mobility Functionality ATM SWITCH Model Layers Sig.Network Layer(SNL) ATM AAL Application

5. OPNET

6. The biggest model 1500 Machines 50 Base Stations 14 ATM Switches 11 UMS / 11 MSCP nodes 250Kb config information 14 days to Run for 400 sec on a dedicated Sun Enterprise (233Mhz)

7. Results

8. MODEL Construction OPNET simulation tool Formal Description Techniques also used Modular Construction Flexibility Expandability

9. Design and construction of a flexible and expandable model of the ATM based fixed part of UMTS for performance assessment of signalling and user data transfer protocols based on OPNET