implementations, make sure to configure identical subnets in such
configurations. IKEv2 supports multiple subnets separated by commas. IKEv1 only
interprets the first subnet of such a definition, unless the Cisco Unity
-extension plugin is enabled.
+extension plugin is enabled. This is due to a limitation of the IKEv1 protocol,
+which only allows a single pair of subnets per CHILD_SA. So to tunnel several
+subnets a conn entry has to be defined and brought up for each pair of subnets.
The optional part after each subnet enclosed in square brackets specifies a
protocol/port to restrict the selector for that subnet.