looks like crashplan does support client-side encryption? is that true? does it require a local mirror disk/folder like dropbox does? I'm really more intereste

looks like crashplan does support client-side encryption? is that true? does it require a local mirror disk/folder like dropbox does? I'm really more interested in a long-term backup storage instead of a folder-sync storage, cold storage is fine but glacier seems a little hard to use and retrieval is expensive.