Choose SAML or OpenID Connect according to the customer identity provider, supported application flow and operational requirements. Compare verified connection capabilities before implementing either protocol.

OIDC uses JSON-based identity responses and JWT ID tokens. SAML uses XML assertions. The format affects implementation tools, but it does not make an unchecked token or assertion trustworthy.

Compare protocol and application requirements

Requirement	OpenID Connect	SAML 2.0
Authentication message	ID token and defined protocol responses	SAML assertion and protocol messages
Common representation	JSON and JWT	XML
Browser integration	Authorization flow and redirect	Commonly browser redirect and form POST bindings
Mobile application planning	Use the appropriate OAuth/OIDC native flow	Often needs a suitable browser or federation arrangement
Trust configuration	Issuer metadata, client settings and verification keys	Entity metadata, endpoints and signing certificates
Application policy	Membership and resource authorization remain separate	Membership and resource authorization remain separate

Use the actual provider's supported flow and profile. A product brand does not guarantee that its configured connection supports your requirements. OpenID Connect Core, SAML technical overview.

Does JSON make OIDC easier to parse?

JSON tooling is convenient for modern application teams. SAML tooling must handle XML structure, namespaces and signature processing. This can change debugging and library selection. It does not make browser-decoded claims a trusted identity. Both protocols need a maintained implementation and their full validation rules.

Keep the browser's transport role separate from the application's trusted validation. Displaying a decoded JWT or assertion can help development. Do not use that display result as an authorization decision.

Validate the protocol you accept

For OIDC, validate the ID token and authorization response according to the selected flow. Bind the expected issuer, audience, nonce and transaction. Use authorization code with PKCE where required. Treat API access tokens separately from ID tokens.

For SAML, use a maintained service-provider library. Validate signature coverage, issuer, audience, recipient, destination, time conditions and response correlation as required by the profile. Read the assertion that the signature verification actually covered.

The 2025 ruby-saml parser-differential vulnerabilities demonstrate a serious implementation failure. They do not establish that all SAML deployments are unsafe or all OIDC deployments are safe. JWT implementations also need explicit defenses against algorithm and token confusion. Original GitHub security research, JWT validation guide.

Ask the customer for a connection brief

Identify the customer's configured identity provider.
Confirm its supported protocol and application profile.
Record the tenant and verified domains.
Identify assignment and provisioning requirements.
Map incoming attributes to reviewed application roles.
Confirm certificate or key rotation ownership.
Define logout and recovery behavior.
Test the required failure cases.

Avoid choosing a protocol from an assumed market share or a generic procurement checklist. A documented customer requirement is stronger evidence than the organization's size or location.

A successful identity-provider login does not establish membership in every tenant with a matching email suffix. Bind each connection to its intended organization. Review role changes independently from profile updates.

Provisioning determines account and membership lifecycle. SSO determines authentication. Logout and token revocation need their own enforcement and tests. Enterprise SSO readiness, joiner, mover and leaver access.

Test the failure and recovery paths

Test a wrong issuer, wrong audience, expired assertion, rotated certificate, replayed response and missing required attribute. Test a user removed from the customer organization who still holds an application session.

Include a federation outage and the approved emergency-access route. Record which account can recover the configuration and how its use is monitored.

Use the SSO logout matrix to determine what remains usable after each logout or revocation action.

Review the connection with NamoID

NamoID provides customer OIDC authentication and has separately configured organization and workforce federation paths. Confirm the required SAML or OIDC connection, environment and product availability with the team before committing to a rollout.

Our engineers can help review tenant routing, session handling and application policy. Share your customer's provider, stack and connection requirements in Slack for an early response. Contact the NamoID team