LTI 1.3. Launch as SSO
Besides SAML 2.0 descibed in the main Single Sign-On article, LTI and in particular its LTI 1.3 launch is can also be used as a sort of Single Sign-On, see LTI (Learning Tools Interoperability)
Just like SAML 2.0 also LTI contains both a trust mechanism so two systems can trust relationship, and security features to validate and ensure the authenticity and integrity of messages.