+-----------------------------------+
          |                                   |
          |               BNG-CP              |
          |                                   |
          +--+--------------+--------------+--+
             |              |              |
  1. Service |   2. Control | 3. Management|
   Interface |    Interface |    Interface |
        (Si) |         (Ci) |         (Mi) |
             |              |              |
             |           ___|___           |
             |       ___(       )___       |
            _|______(               )______|_
           (                                 )
          (         Network/Internet         )
           (________                 ________)
             |      (___         ___)      |
             |          (_______)          |
             |              |              |
             |              |              |
          +--+--------------+--------------+--+
          |                                   |
          |               BNG-UP              |
          |                                   |
          +-----------------------------------+