An umbrella assembly and various embodiments of hub assemblies which provide an umbrellas assembly which is easy to install or remove, is extremely rigid, and is capable of withstanding high wind gusts and other high external forces. A first hub assembly includes a mounting bracket having extended regions for mounting to a hub. A second hub assembly includes securing rings for securely binding mounting brackets to a hub. A third hub assembly includes a mortise-tenon mounting bracket. A fourth hub assembly includes securing rings for securely binding mortise-tenon mounting brackets to a hub. A rib center joint connector having stops is presented. A rotatable fabric connector having a plurality of curved surfaces on the head of the fabric connector is present.