A PointToPoint link should use [IBSS] and directional antenna. A client connection should use an AccessPoint in [BSS]. See the [RFC] for more details

key:%%%
--- = directional
~~~ = omni/panel

     (nodeA)--[IBSS]--(nodeB)
        |               /
        |              /
        |             /
        |            /
        |           /
        |          /
      [IBSS]    optional redundant [IBSS] link
        |        /
        |       /
        |      /
        |     /
        |    /
        |   /
       (nodeC)~~[BSS]~~(client)
        ~  ~
        ~   ~
       [BSS]  [BSS]
        ~      ~
        ~    (client)
        ~
     (client)