What are the connectivity requirements of a Central Services VPN?

What are the connectivity requirements of a Central Services VPN?

A.
Both client and server sites have unlimited connectivity within a Central Service VPN.

B.
Client and server connectivity within the Central Service VPN is defined by the router descriptor within the VRF.

C.
Client sites can only talk to the server sites, server sites have unlimited connectivity within a Central Services VPN.

D.
Client sites have unlimited connectivity within a Central Services VPN, server sites have connectivity only to the clients.