title: What sort of algorithms are involved when an application deciphers the token by the issuer in SSO?
body: <p>In case of claim based authentication which uses SSO, an application receives a token from the issuer for a particular user and that token contains the claims as well as some sort of digital signature in order to be traced by the application that an issuer is a trusted one.
  I want to know, if there are some sort of algorithms involved by which this application recognizes an issuer?
  I had read that issuer has a public key and all the other applications have their own private key, is it true?</p>