Traffic within cluster can consider not being encrypted

[unilinu]

Currently, Traffic from non-leader cnf to the leader one in a cluster is encrypted by wireguard, but it is not necessary.
So, an overley network can be considered among these cnf pods:

1. using a vtep device, for example fleetboard.1 , like flannel.1 in Flannel vxlan mode.
2. cnf pods in a cluster establishes an overlay network.

However this also make the project more complex.