Firebase Authentication is a service that can authenticate users using only client-side code. The OpenID protocol does not rely on a central authority to authenticate a user's identity. Digital signatures can be used to authenticate the source of messages. The display manager must authenticate itself to the server. Any client can authenticate with the Access Point and then attempt to associate. A viewer must authenticate itself before it can connect to a sharing session. These contain biometrics to authenticate the identity of travellers. For example, TLS can authenticate one or both parties using a mutually trusted certificate authority. SIM cards store network-specific information used to authenticate and identify subscribers on the network. The site requires Russian users to authenticate themselves via the social network VK. They witness or authenticate documents to be used abroad. In this example, the user could authenticate 1000 times before the hash chain were exhausted. GCE users must authenticate based on OAuth 2.0 before launching the VMs. OpenVPN has several ways to authenticate peers with each other. This chip handles all the data needed to authenticate a charge.