+ *
+ * An IKE_SA passes various states in its lifetime. A newly created
+ * SA is in the state CREATED.
+ * @verbatim
+ +----------------+
+ ¦ SA_CREATED ¦
+ +----------------+
+ ¦
+ on initiate()---> ¦ <----- on IKE_SA_INIT received
+ ¦
+ +----------------+
+ ¦ SA_CONNECTING ¦
+ +----------------+
+ ¦
+ ¦ <----- on IKE_AUTH successfully completed
+ ¦
+ +----------------+
+ ¦ SA_ESTABLISHED ¦
+ +----------------+
+ ¦
+ on delete()---> ¦ <----- on IKE_SA delete request received
+ ¦
+ +----------------+
+ ¦ SA_DELETING ¦
+ +----------------+
+ ¦
+ ¦ <----- after delete() acknowledged
+ ¦
+ \¦/
+ X
+ / \
+ @endverbatim
+ *