---
title: OpenID Connect client authentication
description: OAuth 2.0 and OpenID Connect clients can use the same authentication methods described in OAuth 2.0 client authentication.
component: pingam
version: 7.2
page_id: pingam:oidc1-guide:oidc-client-auth
canonical_url: https://docs.pingidentity.com/pingam/8.1/am-oidc1/oidc-client-auth.html
llms_txt: https://docs.pingidentity.com/pingam/llms.txt
docs_for_agents: https://developer.pingidentity.com/build-with-ai/docs-for-agents.md
superseded_by: https://docs.pingidentity.com/pingam/8.1/am-oidc1/oidc-client-auth.html
---

# OpenID Connect client authentication

OAuth 2.0 and OpenID Connect clients can use the same authentication methods described in [OAuth 2.0 client authentication](../oauth2-guide/oauth2-client-auth.html).

However, when using OpenID Connect, you must specify in the client profile the type of authentication the client is using. To configure the authentication method, go to Realms > *Realm Name* > Applications > OAuth 2.0 > Advanced, and select one of the following options from the Token Endpoint Authentication Method drop-down menu:

* **client_secret_post**, if the client sends its credentials as form parameters.

* **client_secret_basic**, if the client sends its credentials in a basic authorization header.

* **private_key_jwt**, if the client sends its credentials as a JWT.

* **tls_client_auth**, if the client uses a CA-signed certificate for mutual TLS authentication.

* **self_signed_tls_client_auth**, if the client uses a self-signed certificate for mutual TLS authentication.

* **none**, if the client is public.

  AM will not require a public client to authenticate even if the authentication method is set to a value different from `none`.

During authentication by HTTP POST without a `client_id` parameter, AM stores the POST data on the user-agent in an `AUTH_REQUEST_ATTRIBUTES` cookie. This cookie lets AM continue the authentication process across redirects. AM marks the cookie for deletion on the next successful OAuth 2.0 authorization.