A rogue AP is an unauthorized wireless access point placed on a network to allow access to the network it is attached to.
A rogue AP may be used to attack a network where it would be noticeable to physically connect to the network. It may also refer to an innocently attached wireless access point which is unauthorized.
Rogue APs are a security threat because they allow a physical network to be connected to wirelessly in a manner that is not properly secured. They may be used for gaining access to a physical network so that attacks can be worked on from outside of the building or secure area in which the rogue ap is located.
For questions dealing with wireless access points that are impersonating another access point, the correct tag is evil-twin.
