0     8     16    24    32    40    48    56
+-----+-----+-----+-----+-----+-----+-----+-----+
|                      POW                      |
+-----------------------------------------------+
|                   TIMESTAMP                   |
+-----------------------------------------------+
|       ZONE TYPE       |    ZONE KEY           /
+-----+-----+-----+-----+                       /
/                                               /
/                                               /
+-----+-----+-----+-----+-----+-----+-----+-----+