Access Point Modes (example device: TPLink TLWA500G)

Original Polish version by Lukasz Sawicki
Access Point is a device that connects wireless network to a wired system. So it has to have at least two interfaces: wireless - WLAN - using 802.11 standard, and wired - LAN - using 802.3 standard.
View of the interfaces of TP-Link TL-WA501G Access Point
The interfaces are quite different, which eliminates a risk of mistake. An antenna is connected to the standard SMA R/P connector (in some devices, e.g. Linksys - TNC R/P). 
The example device is TP-Link TL-WA501G N2940. It operates in 802.11 b/g standard, in one of the modes: Access Point, Access Point Client, Repeater, Bridge (Point to Point, Point to Multipoint). The Access Point has useful functions suitable for application in small cells of WLAN. Thanks to WPA/WPA2, WPA-PSK/WPA2-PSK, TKIP/AES encryption and filtering of MAC addresses, the device ensures high security levels. Possibility of connecting an external/outdoor antenna is another big advantage. Simple menu and easy configuration do not bother any installer, even someone starting the job.
Every Access Point can operate in various modes which allow to perform specific functions. Some modes can combine several functions, increasing functionality of the device. The user should choose them carefully, as they may be less stable in comparison with single-function modes. In each case it depends on the features of the device and quality of its software.
The choice of modes of operation available in TP-Link TL-WA501G
Description of the modes of operation
    Access Point - it is the basic mode that allows wireless communication between any client equipped with a wireless card/adapter and the AP. The users (clients) connect to the wireless network in Infrastructuremode.
The structure of a network operating in Access Point mode (Infrastructure)
    Access Point Client - in this mode the device operates similarly to a wireless card/adapter used by clients. This mode has to be used when there is a need of connecting a number of LAN users in a home, office, building - via wireless link. The Access Point can cooperate with a switch (not showed in the diagram below) providing the adequate number of LAN connections.
Access Point Client (APC) mode
    Repeater (regenerator) - the mode used for extending wireless network. The device receives the desired stream of data and sends it further. This mode is often used in larger buildings for ensuring better coverage. Due to the way of work, the maximum throughput of the AP is decreased by 50%.
The idea of Repeater mode
    Bridge (Point to Point) - the mode for creating direct Point-to-Point links, i.e. wireless bridges. It uses static routing based on the MAC addresses of the Access Points. This mode allows to connect distant parts of wired networks. The links are protected against access from other devices. For this mode there are recommended devices coming from the same manufacturer, because it is not standardized.
A Bridge mode (Point to Point) 
      Bridge (Point to Point) with AP mode - combination of functionality of Bridge and Access Point modes. The point-to-point connection does not eliminate possibility of connecting wireless clients.
Combination of Bridge (Point to Point) and Access Point modes
    Bridge (Point to Multipoint) - ensures multiple paths from a single location to multiple locations, i.e. a set of wireless bridges. It uses static routing based on the MAC addresses of the Access Points. This mode allows to connect distant multiple parts of wired networks. The links are protected against access from other devices. For this mode there are recommended devices coming from the same manufacturer, because it is not standardized.
Bridge (Point to Multipoint) option
      Bridge (Point to Multipoint) with AP mode - combination of functionality of Bridge (Point to Multipoint) and Access Point modes. The point-to-multipoint connections do not eliminate possibility of connecting wireless clients.
Combination of Bridge (Point to Multipoint) and Access Point modes
Comparison of different modes of operation

Mode of work

Support for LAN

Support for wireless clients

Mode of operation of the connected counterpart 

Access Point

yes

yes

Repeater, AP client

Access Point Client

yes

no

Access Point

Repeater

no

yes

Access Point

Bridge (Point to Point)

yes

no

Bridge (Point to Point)

Bridge (Point to Point) with AP mode

yes

yes

Bridge (Point to Point), AP client

Bridge (Point to Multi-Point)

yes

no

Bridge (Point to Point)

Bridge (Point to Multi-Point) with AP mode

yes

yes

Bridge (Point to Point), AP client

原文地址:https://www.cnblogs.com/jjkv3/p/2458834.html