+----------------------------------------+
        | I2NSF User  (IPsec Management System)  | 
        +----------------------------------------+
                  |         
       (1)   Flow-based       I2NSF Consumer-Facing 
          Protection Policy      Interface
                  | 
        +---------|------------------------------+
        |         |                              |
        |         |   I2NSF Controller           |
        |         V                              |
        |  +--------------+ (2) +--------------+ |
        |  |Translate into|---->|   NETCONF/   | |
        |  |IPsec Policies|     |   RESTCONF   | |
        |  +--------------+     +--------------+ |
        |                         |     |        |
        +-------------------------|-----|--------+
                                  |     |
       I2NSF NSF-Facing Interface |     |
                                  | (3) |
           |----------------------+     +--|
           V                               V
  +----------------+             +----------------+
  |     NSF A      |             |     NSF B      |
  | IPsec(SPD/SAD) |             | IPsec(SPD/SAD) |
  +----------------+             +----------------+