Heterogeneous Network Project

Heterogeneous Network Project
A banking firm which has decided to grow from a small regional bank into a multistate banking concern, it plans to accomplish this by buying and merging other similar regional banks into its operations. These other banks of course have different IT infrastructures which must be integrated into the final solution, which would result in a heterogeneous network.
Research topics
1. LAN Equipment
2. Wi-Fi technologies
3. VOIP
Apply all these 3 topics in the top a banking firm