It was designed as a way for a remote administrator to login to an installation of KA Lite on one of the zones they manage, as a dummy admin user, to help with debugging/configuration, even without a Django superuser account on the local installation. There's a central endpoint (currently only enabled for central server superusers, for testing) where you pass the IP address of the distributed server (can't be behind a NAT), and it will negotiate a SyncSession and then redirect to the cryptologin endpoint on the distributed server, passing the SyncSession nonce, which logs it in as a dummy admin.