Simplifying Identity Management: A Hands-On Guide to SSO and Security with Microsoft Entra ID (Part 1)

Introduction

In today's cloud-first world, managing user identities and access across multiple applications can be a complex challenge. Single Sign-On (SSO) helps simplify this by enabling users to access multiple applications with one set of credentials. This guide provides a practical, step-by-step approach to implementing SSO using Microsoft Entra ID (formerly Azure Active Directory), while also integrating key security features like Multi-Factor Authentication (MFA) and Conditional Access (CA) to meet modern security requirements.

“Let’s get honest for a moment…”

❓How many apps do you use regularly at work or in your personal life?

❓How many passwords do you think you have?

❓Are they all unique? Or is that one ‘creative’ password doing all the work?”

How would you feel if you could log in once—with one secure password—and get access to everything you need… securely?

The ability to use just one set of credentials to conveniently access all your apps and resources.

No more memorizing multiple credentials or reusing passwords.

Single sign-on in Microsoft Entra?

Enabling SSO with Microsoft Entra ID means users can sign in once to access their Microsoft apps and other cloud, SaaS, and on-premises apps with the same credential.

• Streamlined sign-in experiences
• Increased employee productivity
• Enhanced security
• Increased IT efficiency

What is Single sign-on?

SSO simplifies access, reduces password fatigue, and minimizes security risks associated with password reuse. It enhances productivity while reducing helpdesk calls and administrative overhead.

What is Microsoft Entra ID?

Microsoft Entra ID is Microsoft’s cloud-based identity and access management (IAM) service. It allows organizations to securely manage users, applications, and devices across hybrid environments. It supports protocols like SAML, OAuth, OpenID Connect, and WS-Fed—making it compatible with thousands of third-party and custom apps.

One Login, Many Doors

The Role of Authentication and Authorization in Single Sign-OnI

It's important to understand two fundamental concepts in identity and access management: authentication and authorization, and how they directly relate to Single Sign-On (SSO).

Authentication: Proving Who You Are

Authentication is the process of verifying a user's identity. When users log in—using a password, a biometric scan, or a one-time passcode—they’re proving who they are. In the context of SSO, once a user authenticates through Microsoft Entra ID, they don’t need to re-enter credentials for each connected application. The authentication token issued during the initial login session is trusted across integrated systems.

Common Security Tokens:

• ID Token – Used in OpenID Connect. It contains identity claims (like username, email) and proves the user has authenticated.
• Access Token – Used in OAuth 2.0. It authorizes access to a specific resource (e.g., Microsoft Graph API or a web app).
• SAML Token – An XML-based token used in SAML 2.0 for federated authentication, typically with SaaS apps.
• Refresh Token – Keeps the session alive by issuing new access tokens without re-authenticating.

Authorization: Defining What You Can Do

Authorization occurs after authentication—it determines what actions a user is allowed to perform and which resources they can access. In Microsoft Entra ID, once a user is authenticated through SSO, their access to different applications and data is controlled via:

• Group-based access
• Role-Based Access Control (RBAC)
• Application permissions
• Conditional Access policies

How They Work Together - The SSO Connection

SSO handles authentication once, and then authorization is enforced by each connected app based on the user’s role, attributes, or policies defined in Microsoft Entra ID.

For example:

• A user signs in once using Microsoft Entra credentials (authentication).
• They are granted access to Teams, SharePoint, and Salesforce based on their group membership or assigned roles (authorization).
• Conditional Access may restrict access to Salesforce if the login comes from an unfamiliar location (dynamic authorization control).

SSO simplifies authentication across apps, but authorization ensures users only access what they’re allowed to—together, they provide a secure and efficient access management model.

Single Sign-On Methods

Microsoft Entra ID supports several Single Sign-On (SSO) methods, each designed to accommodate different types of applications, identity models, and security requirements. While organizations can implement a variety of protocols based on their environment, this guide will focus on the three most widely adopted and practical SSO methods for modern identity scenarios.

Understanding the key characteristics of each SSO method helps IT teams strike the right balance between usability and protection.

SAML 2.0 (Secrurity Assertion Markup Language)

How it works: Microsoft Entra ID issues a digitally signed SAML assertion—an XML-based token—after the user is authenticated. This assertion contains the user's identity and attribute information and is securely posted to the application's SAML endpoint (Assertion Consumer Service URL) to establish the session.

Setup Requirements: To configure SAML-based Single Sign-On, you must define:

• Entity ID (unique identifier for the application)
• Reply URL (Assertion Consumer Service URL)
• Signing Certificate (used to validate the token's authenticity)

SAML 2.0 is widely used for enterprise SaaS applications that support federation but not modern protocols like OpenID Connect and is configured via Enterprise Applications in Microsoft Entra.

OpenID Connect (OIDC)

How it works: OpenID Connect is an identity layer built on top of OAuth 2.0. After the user successfully authenticates, Microsoft Entra ID issues an ID token (in JWT format) and optionally an access token. The application validates the ID token to confirm the user's identity and establish a session. OIDC is ideal for modern web and mobile applications.

Setup Requirements: OIDC-based authentication is configured via App Registrations in Microsoft Entra and includes:

• Redirect URIs (where tokens are sent after login)
• Client ID and Secret (where applicable this is needed to secure token)
• Required Scopes (e.g., openid, profile, email)
• Optional: Access token for calling APIs or backends

OIDC is recommended for cloud-native applications, APIs, SPAs, and mobile apps that require standards-based identity and secure token handling using modern protocols.

OAuth 2.0

How it works: OAuth 2.0 is an authorization framework that allows applications to access protected resources (such as APIs) on behalf of a user—without sharing user credentials. After the user signs in (often through OpenID Connect), Microsoft Entra ID issues an access token, which the application uses to call downstream APIs. OAuth 2.0 is not primarily an SSO protocol but is often used in tandem with OIDC for end-to-end identity and access management.

Setup Requirements: OAuth 2.0 is implemented via App Registrations in Microsoft Entra and requires:

• Client ID and Secret (where applicable this is needed to secure token)
• Redirect URIs
• Defined API scopes and permissions
• Access token validation in the calling application

Optional (for enhanced security or automation):

• Certificates for Client Authentication – Instead of a client secret, confidential applications (like backend services or daemon apps) can use a public/private key pair to authenticate securely using client assertions (JWTs signed with the app's certificate).

Use OAuth 2.0 when your app needs to access APIs or services on behalf of a user or itself. Pair it with OIDC when user authentication is also required. Use certificate-based authentication to reduce reliance on secrets and increase security posture—especially in production environments.

How to decide which Single Sign-on Options

Selecting the right method depends on factors like app compatibility, security requirements, and the desired user experience.

Claims and Attributes: The Building Blocks Inside Security Tokens

Once a user successfully authenticates through Microsoft Entra ID, the identity system issues a security token—such as an ID token or access token. But what exactly is inside these tokens that allows applications to authorize access and personalize the user experience?

The answer lies in claims—and behind those claims are attributes.

What Are Claims?

A claim is a verified identity information about a user that is issued by an identity provider (like Microsoft Entra ID) and embedded within a security token (such as an ID token or SAML assertion). Each claim represents a piece of information about the user, such as:

• A user's name (name)
• Their email address (email)
• Assigned roles (roles)
• Group memberships (groups)
• Department or job title (department)

These claims act like digital ID cards, informing the application about who the user is and what they are allowed to do.

What Are Attributes?

Attributes are the source data—stored in the directory (like Microsoft Entra ID or Active Directory). They include:

• First name, last name
• Job title, department
• Country or region
• Employee ID

When a user signs in, these directory attributes are transformed into claims and embedded into the issued token.

How Claims and Attributes Work with Tokens

1. User authenticates with Microsoft Entra ID
2. Entra ID gathers relevant attributes from the directory
3. These attributes are converted into claims
4. Claims are packaged into the ID or Access token
5. The token is sent to the target application
6. The application reads the claims to determine access and tailor the experience

For example, the application is setup to grant access to a dashboard to only users in the HR Department. In this instance the claim & attribute configured will include department attribute in the directory and becomes a department claim in the token, which an app can use to enforce access rules—

Why This Matters

• Claims-based access simplifies authorization
• It supports dynamic access and conditional logic (e.g., based on device, location, or group)
• Enables fine-grained control across thousands of integrated applications

Seamless Flow with Tokens

Just as tokens serve as identity passports in SSO, claims are the identity details stamped inside—and those are pulled directly from directory attributes. Understanding this chain (attributes → claims → tokens → apps) is crucial to designing secure, scalable identity solutions.

Common Terms

Claim:- A statement about a user (e.g., name, role, email) included in a token, used by applications for authorization and personalization.

Attribute:- A piece of identity data stored in a directory (e.g., job title, department) that is used to generate claims during authentication.

Token: A packaged, signed object (like JWT or SAML) issued after authentication that contains claims and other metadata.

A compact, URL-safe token format used in OAuth 2.0 and OpenID Connect, consisting of a header, payload (with claims), and signature.

SAML Assertion: An XML-based token format used in SAML 2.0 for federated SSO. Contains assertions (claims) about the user issued by an identity provider.

Access Token: A token issued after successful authentication, used to access APIs or resources. It includes claims about the user's permissions.

ID Token: Issued via OpenID Connect, it contains identity claims (e.g., name, email) used to identify the user to the application.

Refresh Token: A long-lived token used to obtain new access tokens without re-authenticating the user. Often used in long-running sessions.

Claims Augmentation: The process of enriching or modifying claims (e.g., adding roles, department info) before they are issued in a token.

Claims Mapping: The transformation or redirection of claims to meet app-specific requirements (e.g., renaming email to userPrincipalName).

Audience (aud) Claim: A standard JWT claim that specifies the intended recipient (e.g., app) of the token. Helps prevent token misuse across services.

Issuer (iss) Claim: A standard JWT claim that identifies who issued the token (e.g., Microsoft Entra ID). Used to validate token authenticity.

Subject (sub) Claim: Uniquely identifies the authenticated user across tokens. Remains constant even if other attributes change.

Expiration (exp) Claim:Defines the token's expiry time. Used to enforce session timeouts and limit token validity.

In this phase, we've laid the foundation for what makes modern identity management work: the critical roles of authentication and authorization, the power of security tokens, and how claims and attributes drive decisions behind the scenes. We’ve also explored the different SSO methods supported by Microsoft Entra ID—each designed to provide secure, seamless access based on your organization's needs.

But understanding the concepts is just the beginning.

Now it’s time to put that knowledge into action.

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