So there is a virtual reality device, the Nerve Gear, popularly used for MMOs.
As far as I'm concerned, we never see SAO or Alfheim using any sort of login screen.
Now, it makes sense for SAO to lack a login screen, since you can't log out. But what about Alfheim? How do normal, sane games authenticate their players?
- Do MMO Nerve Gear games use username/password credentials?
- Is it implied anywhere in the series? If I recall correctly, Kirito would just put on his Nerve Gear and instantly enter Alfheim without any sort of password screen.
- Maybe the device serves as the credential itself?
- But if I steal your device, I could impersonate you in all games...
- Besides, using a device ID is not secure at all. If I figure out your device's ID, I could hack mine to use such ID and then login as yourself.
- Perhaps they do some complex biological scan on your body to create an unique ID...
- That doesn't sound very reliable. Or healthy.