This document discusses single sign-on (SSO), which allows a user to use one set of login credentials to access multiple applications. SSO works by authenticating a user once at an authentication domain and then asserting the user's identity to other affiliated domains without requiring additional logins. The document outlines how SSO systems function, their components, dependencies, session management, authentication methods, applications, and advantages and disadvantages. Examples of SSO implementations include logging in with Facebook, Twitter, or LinkedIn to access multiple affiliated sites and services.

1. SINGLE SIGN-ON
Submitted By
Shambhavi Sahay
15869
MCA-VI semester

2.  What is SSO?
 How does SSO work
 Implications of SSO
 SSO products and authentication systems
 SSO real-world examples and applications

3. What is SSO?
 Single sign-on (SSO) is a property
of access control of multiple related, but
independent software systems.
 Multiple systems typically require multiple
sign-on dialogues
◦ E.g. Desktop logon, email, library systems,
external resources …
◦ Multiple sets of credentials
◦ Presenting credentials multiple times

4. What is SSO?
 The more security domains, the more
sign-ons required

5. How does SSO work?

6. Implications of SSO
 Credentials never leave the authentication
domain
 Secondary (affiliated) domains have to
trust the authentication domain
◦ Credentials must be asserted correctly
◦ Protect from unauthorised use
 Authentication transfer has to be
protected

7. Components of SSO

8. Dependencies of SSO
 SSO system relies on other infrastructure
◦ Authentication system
◦ Requires interface with web server
◦ Identity management/registration
 Need to provide for authorisation
◦ Applications often need more than just
authentication information
◦ Attribute information

9. Some other considerations
 Most SSO systems are HTTP based
◦ Browser cookies (restricted to the authentication
domain)
◦ HTTP redirects
 May require integration with application
◦ Agent-based architecture
◦ SSO protocol

10. Some other considerations
 Needs to interact with authentication
system
 Needs protocol between authentication
domain and target application

11. Session Management
 The SSO application maintains a session for
the user
 The target application usually maintains a
session
 Logging out of the target application may not
log you out of the SSO application
 Single Sign-On  Single Sign-Out!
◦ Application specific

12. SSO Methods
 Most SSO systems rely on cookies
◦ Widely accepted and supported by browsers
◦ Users who disable cookies or change browser
security settings may lose SSO capability
 X.509 certificates provide alternative
approach
◦ Require installation on users machine
◦ Need for revocation
◦ Can be confusing for users

13. Supported Authentication Methods
 CAS
◦ LDAP server (OpenLDAP, Active Directory)
◦ Kerberos (MIT, Active Directory)
 Pubcookie
◦ Kerberos v5
◦ LDAP server
◦ /etc/shadow

14. Supported Authentication Methods
 WebAuth
◦ MIT Kerberos
◦ OpenLDAP
 CoSign
◦ Supports GSSAPI
 A-Select
◦ Banking
◦ SMS ‘SURFkey’
◦ LDAP
◦ Radius

15. SSO Applications
 Applications typically require an
‘enforcement agent’
◦ Web server module
◦ Application-level integration
◦ Usually require authorisation info
 Some SSO products utilise a proxy
approach
◦ SSO-enable legacy products without code
change

16. Advantages of SSO
 Reduces the chance of forgetting your
password.
 Reduces IT help desk costs, by reducing
the number of calls to the help desk about
lost password.

17. Advantages of SSO
 Newer technologies are being
implemented to help detect the attempt
to hack a certain system, in which it
would lock out the hacker from the
remaining systems. But, this has more
studying to prove how good it works.

18. Disadvantages of SSO
 Vulnerability problems, such as with
authentication, privacy keys, etc.
 The lacking of a backup stronger
authentication, such as smart cards
or one-time password tokens.

19. Disadvantages of SSO
 The SSO is a highly-critical tool to keep up
always. If the SSO goes out, the user
would lose access to all sites.

20. Examples of Implementations of SSO:-
 Log-in with Facebook
 Log-in with Twitter
 Log-in with Linked-In or Apply with
Linked-In

21. THANK YOU