📘 Topic: Single Sign-On (SSO)

Subject: Information Technology Infrastructure

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1. 📌 Introduction

In modern IT environments, users often need to access multiple applications like email, ERP systems, cloud services, and databases. Remembering separate usernames and passwords for each system becomes difficult and insecure.

👉 To solve this problem, organizations use Single Sign-On (SSO).

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2. ✅ Definition

Single Sign-On (SSO) is a user authentication process that allows a user to log in once and gain access to multiple related systems or applications without re-entering credentials again.

👉 Simple idea: It means “one login for many systems.”

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3. 🎯 Objectives of Single Sign-On

• Reduce password fatigue for users
• Improve user experience
• Increase system security
• Simplify user authentication management
• Reduce helpdesk password reset requests

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4. ⚙️ How Single Sign-On Works

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🔹 Step-by-Step Process

1. User logs in to the SSO system
2. System verifies credentials
3. Authentication token is generated
4. Token is shared with connected applications
5. User accesses multiple systems without logging in again

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📊 Diagram Description

User Login → SSO Server → Authentication Token → Multiple Applications Access

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5. 🧠 Real-Life Example

In a university system:

• Student logs in once to the university portal

• Then automatically accesses:

  • LMS (Learning Management System)
  • Email system
  • Library system

👉 Result:

• No need to log in again for each service

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6. 🔑 Key Components of SSO

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🔹 1. Identity Provider (IdP)

• Authenticates the user 📊 Example: Google, Microsoft

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🔹 2. Service Provider (SP)

• Applications that trust IdP

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🔹 3. Authentication Token

• Digital proof of identity

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7. 📌 Types of Single Sign-On

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🔑 1. Enterprise SSO

• Used within organizations 📊 Example: Company internal systems

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🔑 2. Web-based SSO

• Used for online services 📊 Example: Google login for YouTube, Gmail

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🔑 3. Federated SSO

• Works across different organizations 📊 Example: Google or Facebook login for third-party apps

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8. 📌 Advantages of Single Sign-On

• Easy access to multiple systems
• Reduces password fatigue
• Improves productivity
• Centralized authentication control
• Enhances security (fewer passwords to manage)

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9. ⚠️ Disadvantages of Single Sign-On

• If SSO is hacked, all systems are at risk
• Complex setup and integration
• Dependency on a single authentication system
• Possible downtime affects multiple services

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10. 🔄 SSO vs Traditional Login

Feature	SSO	Traditional Login
Login Required	Once	Multiple times
Security	Centralized	Distributed
User Convenience	High	Low
Management	Easy	Complex

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11. 📝 Likely Exam Questions

⭐ Short Questions:

1. Define Single Sign-On.
2. What is authentication token?
3. What is Identity Provider?
4. Give one advantage of SSO.
5. What is federated SSO?

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⭐ Long Questions:

6. Explain Single Sign-On with diagram.
7. Describe working of SSO in IT systems.
8. Discuss advantages and disadvantages of SSO.
9. Differentiate between SSO and traditional login systems.
10. Explain types of Single Sign-On.

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12. 📌 Quick Summary / Conclusion

• Single Sign-On allows users to log in once and access multiple systems securely.

• It uses:

  • ✔ Identity Provider
  • ✔ Authentication Token
  • ✔ Service Providers

👉 Final Idea: SSO improves security, usability, and efficiency in modern IT infrastructure systems.

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✅ Exam Tip: Always include:

• Definition
• Working process
• Diagram
• Advantages + disadvantages
• Real-life example for full marks