$($d$)$ Two businesses B$1$ and B$2$ intend to connect five nodes using different structural

networking models: peer$-$to$-$peer networking and client$-$server networking. B$1$ requires a

network with a good resource sharing function and low cost. B$2$ needs high network

security and good data back$-$up$.$

$($i$)$ What structural model should be employed by each business? Explain why.

$($ii$)$ Draw schematics of each of these networks.