What is the difference between SSO and SAML?

SSO is what users experience; SAML is one protocol that delivers it. Single sign-on can run on SAML 2.0, OpenID Connect or older protocols, and the user signs in once whichever is used.

Is SSO more secure than separate passwords?

Yes, when the identity provider is well protected. One strong, MFA-protected login replaces many weak or reused passwords and access is revoked in one place — but a compromised IdP account opens every connected app, so its MFA must be strong.

Does SSO replace two-factor authentication?

No, it moves it. The identity provider enforces two-factor authentication at sign-in, so every connected app benefits without running its own MFA prompts.

What is SCIM and do I need it with SSO?

SCIM is a standard API that lets the identity provider create, update and deactivate users in an app automatically. SSO controls logins; SCIM keeps accounts in sync, so leavers lose access without waiting for their next login attempt.

Single Sign-On (SSO) for Messaging Platforms

01 · Definition

What is single sign-on (SSO)?

Single sign-on (SSO) is a login arrangement in which people authenticate once, with their organisation's identity provider (IdP), and are then admitted to many separate applications without a password for each. The IdP — a corporate directory or cloud identity service — holds the account, enforces password and multi-factor rules, and tells each application who the user is.

For a business running WhatsApp customer engagement, SSO usually means agents, supervisors and marketers sign in to the messaging dashboard, CRM and analytics tools with their work account. Access is granted by adding someone to the right directory group, reviewed in one place and revoked by disabling one account when they leave — rather than chasing separate logins across every tool, several of which hold customer conversations and the ability to message customers in the brand's name.

SSO is the user-facing capability; protocols do the work underneath. SAML 2.0 passes a signed XML assertion through the browser and dominates long-established enterprise set-ups; OpenID Connect (OIDC), built on OAuth 2.0, returns a signed JSON Web Token and suits newer web, mobile and API clients. Provisioning is a separate standard: SCIM lets the IdP create and deactivate users in each app. Access to Meta's own tools, such as Meta Business Manager, runs through Meta accounts and business roles, so those logins need protecting as well.

Key takeaways

Single sign-on (SSO) lets staff sign in to many apps with one company identity, managed by an identity provider.
SSO is the capability; SAML 2.0 and OpenID Connect are the protocols that carry the login to each app.
Disabling a person in the identity provider blocks their next login everywhere; pair SSO with SCIM to end existing sessions too.
SSO concentrates risk in the identity provider, so protect it with phishing-resistant multi-factor authentication.
SSO controls who can log in; role-based access control decides what they can do once inside.

See InfiQ pricing

02 · Operation

How does single sign-on (SSO) work?

Connect the app to the IdP
An admin registers the dashboard in the identity provider using SAML metadata or OIDC client settings: entity ID or client ID, the ACS or redirect URL, and the signing certificate or keys.
Assign people through groups
Directory groups such as "WhatsApp agents" and "WhatsApp admins" decide who can open the app and which role their attributes map to.
The user starts a login
Opening the dashboard redirects the browser to the IdP. If the user already has an IdP session they pass straight through; otherwise they sign in once with password and MFA.
The app receives a signed identity
The IdP returns a SAML assertion or an OIDC ID token. The app verifies the signature and claims, creates its own session and applies the mapped role.
Deprovision centrally
Disabling the account in the IdP stops new logins everywhere. With SCIM provisioning the app also deactivates the user and ends active sessions straight away.

03 · Specifications

Single sign-on (SSO): key facts and limits

Protocols	SAML 2.0 (XML) and OpenID Connect (JSON, JWT)
Provisioning standard	SCIM 2.0 (RFC 7643 and 7644)
Login starts	From the app (SP-initiated) or an IdP portal
Who enforces MFA	The identity provider
Not covered	Permissions inside the app (role-based access)
Break-glass access	At least one admin login outside SSO

04 · Rationale

Why does single sign-on (SSO) matter?

Most WhatsApp account incidents are access incidents: a former agent who still has a login, an agency account nobody remembered, a shared password on a sticky note. SSO turns joiners, movers and leavers into a single directory change, gives the security team one place to enforce multi-factor authentication and review access, and gives auditors a clean log. For larger buyers, SSO support in a messaging platform is often a procurement requirement rather than a nice-to-have.

05 · Code samples

Single sign-on (SSO) in code

1# What an admin enters in the identity provider for the dashboard app
2application: whatsapp-dashboard
3protocol: saml2
4sp_entity_id: https://app.example.com/saml/metadata
5acs_url: https://app.example.com/sso/acs        # HTTP-POST binding
6name_id_format: urn:oasis:names:tc:SAML:1.1:nameid-format:emailAddress
7signing:
8  response: true
9  assertion: true
10  algorithm: rsa-sha256
11attributes:
12  email: user.mail
13  display_name: user.displayName
14  groups: user.groups          # whatsapp-admins -> Admin, whatsapp-agents -> Agent
15assigned_groups: [whatsapp-agents, whatsapp-admins]
16session_lifetime: 8h

Illustrative field names; every identity provider labels them slightly differently.

06Playground

A working model of SSO. Use its controls to replay it step by step.

Follow one SSO login, then a leaver

8 / 8

Agent's browser
Messaging dashboardservice provider
Company IdPdirectory + MFA

Step 8 of 8Async

Company IdPMessaging dashboard

SCIM: active = false

Weeks later the agent leaves; access ends without waiting for a login

Request — solid arrow — a call that expects an answer
Response — dashed arrow — the answer coming back
Async — double head — fire-and-forget, nobody waits

Step through an agent's sign-in from the dashboard to the identity provider and back, then watch the IdP deactivate the account through SCIM when the agent leaves.

07 · Cautions

Common mistakes with single sign-on (SSO)

Assuming a disabled IdP account logs people out
Without SCIM or short sessions, a leaver's open dashboard session can keep working for hours or days. Set session lifetimes and use SCIM or the app's admin API to deactivate users immediately.
Leaving local passwords enabled
If the app still accepts email-and-password logins alongside SSO, leavers and attackers can bypass the IdP entirely. Enforce SSO for everyone except one guarded break-glass account.
Weak MFA at the identity provider
SSO makes the IdP the master key to every connected app. Protect it with phishing-resistant factors — passkeys or security keys — not SMS codes alone.
Mapping everyone to admin
Granting the top role by default because group mapping is fiddly undoes the benefit. Map directory groups to least-privilege roles and review membership every quarter.

08 · Recommended practice

Best practices for single sign-on (SSO)

Test SSO with a non-admin account before enforcing it for the whole team.
Keep agency and contractor access in their own directory groups with end dates.
Ask vendors whether SSO and SCIM are included in your plan before you sign.
Send the app's login events to your log platform so IdP and in-app activity line up.

09 · Worked example: Offboarding at a Gurugram logistics firm

Example: Offboarding at a Gurugram logistics firm

A logistics company in Gurugram runs 60 WhatsApp agents across three shifts and connects its messaging dashboard to its corporate identity provider with SSO and SCIM. When a shift lead resigns, HR marks her as a leaver at 6 pm; the directory disables her account, SCIM deactivates her dashboard user within minutes and her open session on a shared terminal ends. The monthly access review, which used to mean comparing three spreadsheets, is now one report of who sits in the two WhatsApp groups.

10 · Questions and answers

SSO FAQs

What is the difference between SSO and SAML?: SSO is what users experience; SAML is one protocol that delivers it. Single sign-on can run on SAML 2.0, OpenID Connect or older protocols, and the user signs in once whichever is used.
Is SSO more secure than separate passwords?: Yes, when the identity provider is well protected. One strong, MFA-protected login replaces many weak or reused passwords and access is revoked in one place — but a compromised IdP account opens every connected app, so its MFA must be strong.
Does SSO replace two-factor authentication?: No, it moves it. The identity provider enforces two-factor authentication at sign-in, so every connected app benefits without running its own MFA prompts.
What is SCIM and do I need it with SSO?: SCIM is a standard API that lets the identity provider create, update and deactivate users in an app automatically. SSO controls logins; SCIM keeps accounts in sync, so leavers lose access without waiting for their next login attempt.

Single Sign-On(SSO)

Properties

What is single sign-on (SSO)?

How does single sign-on (SSO) work?

Connect the app to the IdP

Assign people through groups

The user starts a login

The app receives a signed identity

Deprovision centrally

Single sign-on (SSO): key facts and limits

Why does single sign-on (SSO) matter?

Single sign-on (SSO) in code

06Playground

Follow one SSO login, then a leaver

Common mistakes with single sign-on (SSO)

Assuming a disabled IdP account logs people out

Leaving local passwords enabled

Weak MFA at the identity provider

Mapping everyone to admin

Best practices for single sign-on (SSO)

Example: Offboarding at a Gurugram logistics firm

SSO FAQs

See how this works on InfiQ

Put SSO to work

See how this works on InfiQ