Wireless protocol standards determine the advantages and disadvantages of wireless networks (I)

Today, with the proliferation of wireless networks, many people are confused about which kind of wireless technology is better? In fact, we are not quite clear that the difference between wireless networks depends on their wireless protocol standards. Each type of wireless protocol has its own characteristics. The following is a detailed introduction.

802.11 wireless protocol standard is a wireless LAN Standard originally developed by ieee. It is mainly used to solve the wireless access between users and user terminals in office LAN and campus network. The business is mainly limited to data access, the maximum speed is 2 mbps. Because it cannot meet people's needs in terms of speed and transmission distance, the ieee team has successively introduced two new standards, 802.11b and 802.11a. The former has become the mainstream standard, the latter is also favored by many manufacturers.

802.11a wireless protocol standard

802.11awi-fi5) is a follow-up standard that is widely used in 802.11b. It operates in the 5ghzu-nii band, the physical layer speed can reach 54 mbps, and the transmission layer can reach 25 mbps. It provides 25 Mbps wireless atm interface, 10 Mbps Ethernet Wireless Frame Structure interface, and tdd/tdma air interface. It supports voice, data, and image services. One sector can be connected to multiple users, each user can carry multiple user terminals.

Ieee 802.11b wireless protocol standard

Ieee 802.11b is a standard for wireless LAN. The carrier frequency is 2.4 ghz and the transmission speed is 11 mbit/s. Ieee 802.11b is the most famous and widely used standard in all wireless LAN standards. It is sometimes incorrectly labeled as Wi-Fi. In fact, Wi-Fi is a trademark of wlana of the wireless LAN alliance. This trademark only ensures that the products using this trademark can cooperate with each other, and it does not actually matter with the standard itself. A total of 14 22 MHz channels are available in the 2.4-ghz-ism band. The subsequent standard of ieee 802.11b is ieee 802.11 GB, and its transmission speed is 54 mbit/s.

802.11c wireless protocol standard

802.11c is extended at the mac/llc level to develop wireless bridging operation standards, but later added to the existing 802.1 to become 802.1d.

801.11d wireless protocol standard

Like 802.11c, it expands the media access control/link Connection Control (mac/llc) layer, corresponding to the 802.11b standard, to solve the problem of countries that cannot use the GHz band.

802.11e wireless protocol standard

802.11e is a wlan standard developed by ieee to meet qos requirements. Qos is an important indicator in the transmission of voice and video. In the 802.11mac layer, the qos function is added to 802.11e. Its distributed control mode can provide stable and reasonable service quality, while the centralized control mode can flexibly support multiple service quality policies, the Wi-Fi Alliance calls it wmm (wi-fi multimedia ).

802.11f wireless protocol standard

The iappinter-access point protocol (iappinter) protocol is added to 802.11f to ensure that the user is roaming between different access points, so that the user can smoothly and implicitly switch the access area. The 802.11f standard determines the login of an access point in the same network and the information exchange between users switching from one access point to another.