+--------+                +--------------+
          | Device |                |Config server |
          +--------+                |(e.g., TFTP)  |
                                    +--------------+
+---------------------------+    +------------------+
| +-----------+             |    |                  |
| |           |             |    |                  |
| |   DHCP    |             |    |                  |
| |           |             |    |                  |
| +-----+-----+             |    |                  |
|       |                   |    |                  |
| +-----v------+            |    |  +-----------+   |
| |            |            |    |  | Encrypted |   |
| |Fetch config|<------------------>|  config   |   |
| |            |            |    |  |   file    |   |
| +-----+------+            |    |  +-----------+   |
|       |                   |    |                  |
|       X                   |    |                  |
|      / \                  |    |                  |
|     /   \ N    +--------+ |    |                  |
|    | Enc?|---->|Install,| |    |                  |
|     \   /      |  Boot  | |    |                  |
|      \ /       +--------+ |    |                  |
|       V                   |    |                  |
|       |Y                  |    |                  |
|       |                   |    |                  |
| +-----v------+            |    |                  |
| |Decrypt with|            |    |                  |
| |private key |            |    |                  |
| +-----+------+            |    |                  |
|       |                   |    |                  |
|       v                   |    |                  |
|      / \                  |    |                  |
|     /   \ Y    +--------+ |    |                  |
|    |Sane?|---->|Install,| |    |                  |
|     \   /      |  Boot  | |    |                  |
|      \ /       +--------+ |    |                  |
|       V                   |    |                  |
|       |N                  |    |                  |
|       |                   |    |                  |
|  +----v---+               |    |                  |
|  |Retry or|               |    |                  |
|  | abort  |               |    |                  |
|  +--------+               |    |                  |
|                           |    |                  |
+---------------------------+    +------------------+