principal
                                ^
                                |
                                |
   +----------------------------|-------------+
   | SNMP engine                v             |
   |                    +--------------+      |
   |                    |              |      |
   |  +-----------------| securityName |---+  |
   |  | Security Model  |              |   |  |
   |  |                 +--------------+   |  |
   |  |                         ^          |  |
   |  |                         |          |  |
   |  |                         v          |  |
   |  |  +------------------------------+  |  |
   |  |  |                              |  |  |
   |  |  | Model                        |  |  |
   |  |  | Dependent                    |  |  |
   |  |  | Security ID                  |  |  |
   |  |  |                              |  |  |
   |  |  +------------------------------+  |  |
   |  |                         ^          |  |
   |  |                         |          |  |
   |  +-------------------------|----------+  |
   |                            |             |
   |                            |             |
   +----------------------------|-------------+
                                |
                                v
                             network

lol