VpN, SSl in info sec

1. PRESENTATION
SSL and TLS

2. Secure Socket Layer (SSL)
Secure Socket Layer (SSL) provides
security to the data that is transferred
between web browser and server.
 SSL encrypts the link between a web server
and a browser which ensures that all data
passed between them remain private and free
from attack.

4. Position of SSL

5. SSL Goals
Confidentiality
Integrity Protection
Authentication

6. SSL Protocols
SSL record protocol
Handshake protocol
Change-cipher spec protocol
Alert protocol

8. Handshake Protocol

10. Phase I of Handshake Protocol
After Phase I, the client and server know the
following:
 The version of SSL
The algorithms for key exchange, message
authentication, and encryption
 The compression method
 The two random numbers for key
generation

12. Phase II of Handshake Protocol
After Phase II,
The server is authenticated to the client.
The client knows the public key of the
server if required.

14. Phase III of Handshake Protocol
After Phase III,
The client is authenticated for the server.
 Both the client and the server know the
pre-master secret.

16. Phase IV of Handshake Protocol
After Phase IV, the client and server are
ready to exchange data.

17. SSL Record Protocol
SSL Record provides two services to SSL
connection.
Confidentiality
Message Integrity
Fragmentation
Compression
Message Authentication and Integrity
Protection
Encryption

19. Alert Protocol
Error messages (fatal alerts and warnings)

20. Change-cipher spec protocol
Change-cipher protocol consists of a single
message which is 1 byte in length and can
have only one value.
This protocol’s purpose is to cause the
pending state to be copied into the current
state.

21. Evaluation of SSL
SSL 1.0
was never released to the public.
SSL 2.0
was released in 1995.
SSL 3.0
was released in 1996.
SSLv4.0 or TSLv1.0
was released in 1999.
TLSv1.1
was released in 1999.

22. Transport Layer Security
Transport Layer Security (TLS) was designed
to provide security at the transport layer.
TSL was derived from a security protocol called
Secure Socket Layer(SSL).
TSL is the successor to the Secure Socket Layer
(SSL).
TSL is a protocol that ensures privacy between
communicating applications and their users on
the internet.