Benefits of WLANWLAN technology first appeared in the United States. It was primarily used as a wireless extension of the last-mile network and was mainly applied in households. At that time, the American people had a strong demand for wireless Internet access due to the cabling difficulties (most Americans living in villas with courtyards) and the popularity of laptops and tablets. This in turn accelerated the proliferation of WLANs. Show
Compared with wired networks, WLANs have the following benefits:
Is WLAN and Wi-Fi the Same Thing?Wi-Fi is a trademark of the WFA, and is also a wireless network communication technology based on IEEE 802.11. The WFA has announced the use of Wi-Fi to improve the interoperability of products in compliance with IEEE 802.11 standards. WLAN is short for wireless local area network. Quite simply, WLANs provide network communication using radio waves such as lasers and infrared signals, instead of physical connections. They provide wireless network communication using high-frequency radio waves (such as those on the 2.4 GHz and 5 GHz frequency bands) and comply with IEEE 802.11 standards. WLAN in our daily life refers to that implemented based on IEEE 802.11 standards. During the evolution and development of WLAN, various technical standards have emerged, such as Bluetooth, Wi-Fi, and HyperLAN2. Among them, Wi-Fi is now most commonly used due to its advantages such as simple implementation, reliable communication, high flexibility, and low implementation costs. Gradually, Wi-Fi becomes a synonym of WLAN. Simply put, WLAN is a network system, while Wi-Fi is a technology in this network system. Therefore, WLAN includes Wi-Fi. Are WLANs Secure?WLANs are easy to deploy and expand, flexible, and cost-effective. On WLANs, service data is transmitted through radio signals. As such, service data can easily be intercepted or tampered with by attackers when being transmitted on open wireless channels. Common WLAN security threats are as follows:
To cope with the preceding security threats, differentiated security protection measures are required to protect against network attacks, for example:
WLAN RoamingOn a WLAN, users require mobile communication. The signal coverage of a single AP, however, is limited. As such, users often move from the coverage area of an AP to that of another AP. To prevent network interruptions while users move between different APs, the concept of WLAN roaming is introduced. WLAN roaming is a process wherein a station (STA) — when moving to the boundaries between two APs — associates with the new AP and disconnects from the original AP, during which connections are not interrupted. Simply put, WLAN roaming is similar to cell handover for a mobile phone. When a mobile phone moves from the coverage area of a base station to that of another base station, the mobile phone still enjoys uninterrupted and seamless call experiences. Common WLAN roaming technologies include traditional roaming, fast roaming, smart roaming, and lossless roaming. Basic Elements of WLAN
WLAN Networking ModesIn enterprise scenarios, typical WLAN networking modes include the following:
How Does WLAN Work?On a WLAN, the transmit end first applies source coding to convert information into digital signals that allow for circuit calculation and processing, and then into radio waves by means of channel coding and modulation. After receiving the radio waves, the receive end demodulates and decodes the radio waves and converts them into information. The information may be an image, a text, a sound, or the like. The transmit and receive ends are connected over interfaces and channels.
What is a wireless local area network that provides Internet access to the public?Wireless LAN
Wireless LAN (WLAN) technology provides internet access within a building or a limited outdoor area. First used within offices and homes, WLAN technology is now also used in stores and restaurants.
What is a type of wireless local area network?WLANs use high-frequency radio waves and often include an access point to the Internet. A WLAN allows users to move around the coverage area, often a home or small office, while maintaining a network connection. A WLAN is sometimes called a local area wireless network (LAWN).
What are the two types of wireless LANS?Types of WLANS
Infrastructure Mode − Mobile devices or clients connect to an access point (AP) that in turn connects via a bridge to the LAN or Internet. The client transmits frames to other clients via the AP. Ad Hoc Mode − Clients transmit frames directly to each other in a peer-to-peer fashion.
What is local area network called?A local area network (LAN) consists of a series of computers linked together to form a network in a circumscribed location. The computers in a LAN connect to each other via TCP/IP ethernet or Wi-Fi.
|