iocage supports two provisioning types, thick (default) and thin. Thin is basically a ZFS clone of the base jail. If you plan to replicate the jail over the network with ZFS send/receive use the default thick provisioning! This will create a fully independent jail copy which can be sent over the network with ZFS send/receive.
Create a normal jail
iocage create tag=myjail or just iocage create
Create a thin jail
iocage create -c tag=myjail