Maximum signal distance depends on several factors

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Maximum signal distance depends on several factors, including obstructions, antenna strength, and interference. For example, for communications in a typical environment (with one or two walls), the actual distance would be roughly half of the maximum. Because transmission speeds decrease with distance, you can either achieve the maximum distance or the maximum speed, but not both. The ability of newer devices to communicate with older devices depends on the capabilities of the transmit radios in the access point. o Some 802.11n devices are capable of transmitting at either 2.4 GHz or 5 GHz. However, a single radio cannot transmit at both frequencies at the same time. When you connect a legacy device to the wireless network, all devices on the network operate at the legacy speed. For example, connecting an 802.11b device to an 802.11n or 802.11g access point slows down the network to 802.11b speeds. A dual band access point can use one radio to transmit at one frequency, and a different radio to transmit at a different frequency. For example, you can configure many 802.11n devices to use one radio to communicate at 5 GHz with 802.11a devices, and the remaining radios to use 2.4 GHz to communicate with 802.11n devices. Dual band 802.11a and 802.11g devices are also available. When you configure an access point, some configuration utilities use the term mixed mode to designate a network with both 802.11n and non-802.11n clients. In this configuration, one radio transmitter is used for legacy clients, and the remaining radio transmitters are used for 802.11n clients. Many 802.11n access points can support clients running other wireless standards (802.11a/b/g). When a mix of clients using different standards are connected, the access point must disable some 802.11n features to be compatible with non-802.11n devices, which decreases the effective speed. Some newer 802.11a and 802.11g devices provide up to 108 Mbps using 802.11n pre-draft technologies (MIMO and channel bonding).
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Wireless Security 0:00-0:46 Wireless networks are an unbounded network medium. This means the transmission broadcast can be picked up by anyone in a range of the wireless access point. And with some wireless networks, this could be over 150 feet away from the access point. Because of this, wireless networks use two types of security measures in order to protect wireless communications and broadcasts. The first security measure is authentication. The first thing that occurs when connecting a device to a wireless network is authentication.Authentication is the process of proving identity. You are essentially telling the wireless access pointthat you are allowed to be on the network. Wireless networks use a few different methods for authentication. The first method is open authentication. Open Authentication 0:47-1:21 Open authentication uses MAC address filtering to permit or deny connections, and there are two ways to implement this. The first is implicit deny. This means that all MAC addresses are denied access by default and only the MAC addresses on an allowed list are able to connect. The second way is called explicit deny. With this method, all MAC addresses are allowed by default, and the list is instead used to deny specific MAC
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