Question $1|$

In IEEE $802\mathrm{.}11,$ open system authentication consists of two communications. An authentication is requested by the client which contains the station ID $($typically its MAC address$).$ This is followed by a response from the access point $($AP$)$ containing a success or failure message. A failure could occur if the MAC address of the station is explicitly excluded from network access in the router configuration.

a$.$ what are the benefits of this authentication scheme?

b$.$ what are the security vulnerabilities of this authentication scheme?