olemus
juurdepääsu taotleva rakenduse ühene autentimiseks kasutatav identifikaator, parooli analoog

täpsemalt
http://csharpcorner.mindcrackerinc.netdna-cdn.com/UploadFile/ff2f08/token-based-authentication-using-Asp-Net-web-api-owin-and-i/Images/Based%20Authentication.jpg

https://scotch.io/tutorials/the-ins-and-outs-of-token-based-authentication