Detection Method, Apparatus, and System

A detection method includes: obtaining at least one feature of a first access point (AP), where the at least one feature includes a quantity of target terminals that request to access the first AP within a time period with duration being first duration, and the target terminal is a terminal whose access status is abnormal; and detecting, based on the at least one feature, whether the first AP is a logical edge AP, where the logical edge AP is an AP whose signal coverage area reaches an edge of a signal coverage area of a wireless local area network (WLAN) in which the AP is located.