open system authentication (WLAN) (OSA)

Open System Authentication(OSA) is the standard authentication in WLANs according to IEEE 802.11. It is an open authentication, which is also called unsecured.

Authentication is insecure if the wireless access point( WAP) is not configured for encryption. In such a case, any wireless client can connect to the WLAN.

With OSA authentication, the client sends a request to the access point. The access point sends the authentication to the client, which can then log on to the network. If the access point is encrypted with Wired Equivalent Privacy(WEP), then this key can also be used for authentication. On the other hand, the authentication data can also be exchanged with the clients. Authentication is optional and not mandatory in the standard. Shared Key Authentication( SKA) is available as an alternative to open authentication.