Google Authenticator available as a public service?

Question

Is there public API for using the Google Authenticator (two factor authentication) on self-running (e.g. LAMP stack) web apps?

Answer 1

Yes, need no network service, because Google Authenticator app won't communicate with the google server, it just keeps synced with the initital secret that your server generate(input into your phone from QR code) while the time pass.