Infrastructure mode:
• Infrastructure mode is the most common mode to operate and is the factory default setting.
• Infrastructure mode is used when a PC is connected to a wireless access point or to a wireless router.
• If the hosts are connected to the network via a base station or an access point (fixed infrastructure), then the network is said to be operating in infrastructure mode.
• Cellular networks work in infrastructure mode because all the cell phones connect to the network through the base stations (cell towers).
When a network is not in infrastructure mode, then it is said to be operating in Ad hoc mode of operation.
• In an Ad hoc mode of operation, the wireless hosts can communicate with each other without an access point.
• No fixed infrastructure such as access point is required for the wireless hosts.
Difference between Ad-hoc mode of operation and infrastructure mode:

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