Vertical Federated Learning functionality

[TanvirHundredOne]

What is your question?

I am looking into Vertical Federated Learning examples. Simulation works with

hist = fl.simulation.start_simulation(
    client_fn=client_fn,
    num_clients=3,
    config=fl.server.ServerConfig(num_rounds=1000),
    strategy=Strategy(label),
)

code base. But how does start_simulation method knows its a vertical fl, other than data composition for each client there seems to be no way for the simulator to know whether its vertical or not or am I missing something obvious?

TIA