Wi-Fi networks are built using wireless adapters, access points, and repeaters. Figure 8-8 illustrates.

Figure 8-8 Wi-Fi Network Components

Figure 8-8 shows the following components:
• Wi-Fi connected devices, such as a laptop computer (host), a printer, a desktop computer (host), and a handheld device—a cellular telephone, tablet, or similar. Each device must have a Wi-Fi modulator/demodulator (MODEM). Most devices have Wi-Fi MODEMS, antennas, and other components built into the device. Desktop computers are the least likely item shown in the figure to have a Wi-Fi interface, but you can generally add one through an interface card or USB port. You can find more information at https://www.acedexam.com/500-420-caapa-cisco-appdynamics-associate-performance-analyst/

• The access point, or AP, bridges between the Wi-Fi and wired networks. Standalone APs act like a switch on a wired network; they copy IP packets from the wireless network to the wired network, replacing the outer physical packet encapsulation from the wireless network with the correct physical encapsulation for the wired network.

• The repeater, which repeats any received wireless signals to Wi-Fi devices too far away to receive the signal from the AP.

In most smaller networks, such as small businesses and residential settings, the AP and router are combined into a single wireless router.

Wi-Fi Mesh Systems

Typical Wi-Fi signals will travel around 30 meters or 100 feet in typical indoor settings. This might seem like a lot, but the maximum distance between any points in a large house is longer than what might be immediately obvious. For instance, in a house with three floors:
• A typical floor in a house will be around 10 feet (or 3 meters), so a three-story house will be around 30 feet (or 10 meters) tall, excluding any attic space.
• A typical floor in a house can be around 10 meters by 10 meters (or around 30 feet by 30 feet).
• The distance between opposite corners on the top and bottom floors can be 15 meters (or 50 feet).

Each wall or floor the Wi-Fi signal passes through reduces its strength by 10%–15%. Given these parameters, or intervening kitchen appliances, televisions, and other factors, you do not need to live in a large house to run out of Wi-Fi signal.
One solution to this problem is to install a repeater, as noted previously, but this can be challenging in some situations, and repeaters do not always yield the best Wi-Fi performance.

An alternate solution is installing a Wi-Fi mesh system. Figure 8-9 illustrates such a system.

Figure 8-9 Wireless Mesh System Operation

In Figure 8-9, two Wi-Fi APs are connected via a backhaul, creating a Wi-Fi mesh. When a packet is received from the router for some host wirelessly connected to A, AP B will send this packet along the backhaul to A for transmission to the host. From the user’s perspective, A and B combine to create a single Wi-Fi system. Users can roam between the two APs without losing their connection.

The backhaul can be a wired Ethernet if Ethernet cabling is available between the two locations. The backhaul can also be a wireless connection if no physical cabling is available. In the case of a wireless connection, the two APs will choose an otherwise unused channel or use beam forming to create a narrow wireless connection over which they will send packets to one another.

Wi-Fi mesh systems can extend the range of a Wi-Fi system to large distances under the administration of a single network operator.