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Transport Layer Security
(TLS)
Secure Socket Layer
(SSL)
Group Members: Roll No.
Ali Akber 1406
Rana Assad Ali 1407
Qasim Ali 1425
Toseef Khadim 1427
BS(cs 4rth smester)
Topic
SSL
(Secure Socket Layer)
SSL History
 Netscape developed The Secure Sockets Layer Protocol
(SSL) in 1994, as a response to the growing concern over
security on the Internet.
 SSL was originally developed for securing web browser and
server communications.
 SSL v3.0 was specified in an Internet Draft (1996)
SSL (Secure Socket Layer)
 SSL is a Secure Sockets Layer
 SSL is the standard security technology for establishing an
encrypted link between a web server and a browser.
 This link ensures that all data passed between the web
server and browsers remain private and integral
 There are several versions of the SSL protocol defined. The
latest version, the Transport Layer Security Protocol (TLS),
is based on SSL 3.0
SSL Version 1.0
SSL Version 2.0
SSL Version 3.0
Where SSL fits?
HTTP SMTP POP3
80 25 110
HTTPS SSMTP SPOP3
443 465 995
Secure Socket Layer
Transport
Network
Data Link
Port
No.
SSL architecture
SSL
Handshake
Protocol
SSL change
Cipher Spec
Protocol
SSL Alert
Protocol
Applications
(e.g., HTTP)
SSL Record Protocol
TCP
IP
SSL
 It is the most widely known as the protocol that, coupled
with HTTP, secures the Web and uses the “https” URI
scheme
SSL components
 SSL Handshake Protocol
 Negotiation of security algorithms and parameters
 Key exchange
 Server authentication and optionally client authentication
 SSL Record Protocol
 Fragmentation
 Compression
 Message authentication and integrity protection
 Encryption
 SSL Alert Protocol
 Error messages (fatal alerts and warnings)
 SSL Change Cipher Spec Protocol
 A single message that indicates the end of the SSL handshake
SSL Goals
 Confidentiality
 The data being transmitted over the Internet or network needs confidentiality. In
 other words, people do not want their credit card number, account login,
 passwords or personal information to be exposed over the Internet.
 Integrity Protection
 The data needs to remain integral, which means that once credit card details and
 the amount to be charged to the credit card have been sent, a hacker sitting in
 the middle cannot change the amount to be cha rged and where the funds should
 go.
 Authentication
 Your organization needs identity assurance to authenticate itself to customers /
 extranet users and ensure them they are dealing with the right organization.
 Your organization needs to comply with regional, national or international
 regulations on data privacy, security and integrity
Reality!!!
Transport Layer Security
(TLS)
Two protocols are dominant today for providing
security at the transport layer
 Secure Sockets Layer (SSL) protocol
 Transport Layer Security (TLS) protocol
Definition:
 Transport Layer Security (TLS) was designed to
provide security at the transport layer.
 TLS was derived from a security protocol called
Secure Sockets Layer (SSL).
Transport Layer Security
(TLS)
 TLS is the successor to the Secure Sockets Layer (SSL).
 Transport Layer Security (TLS) is a protocol that ensures
privacy between communicating applications and their
users on the Internet.
 Is a widely deployed protocol for securing client-server
communications over the internet.
 TLS is designed to prevent eavesdropping, tampering,
and message forgery
Why do we need it?
 TLS ensures that no third party may eavesdrop or
tamper with any message.
Working of Transport Layer
Security
 The Client connect to server (using TCP). The client can
be anything.
 The Client sends a number of specifications :
 Version of SSL/TLS
 Which cipher suites, compression method it wants to use.
Ver : TLS
1.2
CS:RSA,DSA
,RC4
COMPMETH
OD
Working of Transport Layer
Security
 The server checks what the highest SSL/TLS version is
that is supported by them both, picks a cipher suite from
one of the client's options (if it supports one), and
optionally picks a compression method.
Client
Ver : TLS
1.2 
CS:
RSA 
DSA
RC4
COMPMETH
OD
Server
Ver : TLS
1.1
1.2
1.3
CS:RSA 
COMPMETHOD
Working of Transport Layer
Security
 After this the basic setup is done, the server sends its
certificate.
 This certificate must be trusted by either the client itself
or a party that the client trusts.
 For example if the client trusts GeoTrust, then the client
can trust the certificate from Google.com, because
GeoTrust cryptographically signed Google's certificate.
Working of Transport Layer
Security
 Having verified the certificate and being certain this
server really is who he claims to be (and not a man in
the middle), a key is exchanged.
 This can be a public key, a "PreMasterSecret" or simply
nothing, depending on the chosen ciphersuite.
Working of Transport Layer
Security
 Both the server and the client can now compute the key
for the symmetric encryption.
0100100001100
1010110110001
1011000110111
1
Hello
Working of Transport Layer
Security
 The handshake is now finished, and the two hosts can
communicate securely.
Working of Transport Layer
Security
 To close the connection, a close notify 'alert' is used. If
an attacker tries to terminate the connection by finishing
the TCP connection (injecting a FIN packet), both sides
will know the connection was improperly terminated.
The connection cannot be compromised by this though,
merely interrupted
Ok. Gtg
bye..
Ok see you
later. TC
Benefits of TLSSSL
 Encryption
 TLS can help to secure transmitted data using encryption.
 Interoperability
 TLS works with most Web browsers, including Microsoft Internet Explorer and Netscape
Navigator, and on most operating systems and Web servers.
 Algorithm flexibility
 TLS provides options for the authentication mechanisms, encryption algorithms, and
hashing algorithms that are used during the secure session.
 Ease of deployment
 Many applications use TLS transparently on a Windows Server 2003 operating systems.
 Ease of use
 Because you implement TLS beneath the application layer, most of its operations are
completely invisible to the client.
Govt municipal degree college Faisalabad

More Related Content

Ssl and tls

  • 1. Transport Layer Security (TLS) Secure Socket Layer (SSL) Group Members: Roll No. Ali Akber 1406 Rana Assad Ali 1407 Qasim Ali 1425 Toseef Khadim 1427 BS(cs 4rth smester) Topic
  • 3. SSL History  Netscape developed The Secure Sockets Layer Protocol (SSL) in 1994, as a response to the growing concern over security on the Internet.  SSL was originally developed for securing web browser and server communications.  SSL v3.0 was specified in an Internet Draft (1996)
  • 4. SSL (Secure Socket Layer)  SSL is a Secure Sockets Layer  SSL is the standard security technology for establishing an encrypted link between a web server and a browser.  This link ensures that all data passed between the web server and browsers remain private and integral  There are several versions of the SSL protocol defined. The latest version, the Transport Layer Security Protocol (TLS), is based on SSL 3.0 SSL Version 1.0 SSL Version 2.0 SSL Version 3.0
  • 5. Where SSL fits? HTTP SMTP POP3 80 25 110 HTTPS SSMTP SPOP3 443 465 995 Secure Socket Layer Transport Network Data Link Port No.
  • 6. SSL architecture SSL Handshake Protocol SSL change Cipher Spec Protocol SSL Alert Protocol Applications (e.g., HTTP) SSL Record Protocol TCP IP
  • 7. SSL  It is the most widely known as the protocol that, coupled with HTTP, secures the Web and uses the “https” URI scheme
  • 8. SSL components  SSL Handshake Protocol  Negotiation of security algorithms and parameters  Key exchange  Server authentication and optionally client authentication  SSL Record Protocol  Fragmentation  Compression  Message authentication and integrity protection  Encryption  SSL Alert Protocol  Error messages (fatal alerts and warnings)  SSL Change Cipher Spec Protocol  A single message that indicates the end of the SSL handshake
  • 9. SSL Goals  Confidentiality  The data being transmitted over the Internet or network needs confidentiality. In  other words, people do not want their credit card number, account login,  passwords or personal information to be exposed over the Internet.  Integrity Protection  The data needs to remain integral, which means that once credit card details and  the amount to be charged to the credit card have been sent, a hacker sitting in  the middle cannot change the amount to be cha rged and where the funds should  go.  Authentication  Your organization needs identity assurance to authenticate itself to customers /  extranet users and ensure them they are dealing with the right organization.  Your organization needs to comply with regional, national or international  regulations on data privacy, security and integrity
  • 12. Two protocols are dominant today for providing security at the transport layer  Secure Sockets Layer (SSL) protocol  Transport Layer Security (TLS) protocol
  • 13. Definition:  Transport Layer Security (TLS) was designed to provide security at the transport layer.  TLS was derived from a security protocol called Secure Sockets Layer (SSL).
  • 14. Transport Layer Security (TLS)  TLS is the successor to the Secure Sockets Layer (SSL).  Transport Layer Security (TLS) is a protocol that ensures privacy between communicating applications and their users on the Internet.  Is a widely deployed protocol for securing client-server communications over the internet.  TLS is designed to prevent eavesdropping, tampering, and message forgery
  • 15. Why do we need it?  TLS ensures that no third party may eavesdrop or tamper with any message.
  • 16. Working of Transport Layer Security  The Client connect to server (using TCP). The client can be anything.  The Client sends a number of specifications :  Version of SSL/TLS  Which cipher suites, compression method it wants to use. Ver : TLS 1.2 CS:RSA,DSA ,RC4 COMPMETH OD
  • 17. Working of Transport Layer Security  The server checks what the highest SSL/TLS version is that is supported by them both, picks a cipher suite from one of the client's options (if it supports one), and optionally picks a compression method. Client Ver : TLS 1.2  CS: RSA  DSA RC4 COMPMETH OD Server Ver : TLS 1.1 1.2 1.3 CS:RSA  COMPMETHOD
  • 18. Working of Transport Layer Security  After this the basic setup is done, the server sends its certificate.  This certificate must be trusted by either the client itself or a party that the client trusts.  For example if the client trusts GeoTrust, then the client can trust the certificate from Google.com, because GeoTrust cryptographically signed Google's certificate.
  • 19. Working of Transport Layer Security  Having verified the certificate and being certain this server really is who he claims to be (and not a man in the middle), a key is exchanged.  This can be a public key, a "PreMasterSecret" or simply nothing, depending on the chosen ciphersuite.
  • 20. Working of Transport Layer Security  Both the server and the client can now compute the key for the symmetric encryption. 0100100001100 1010110110001 1011000110111 1 Hello
  • 21. Working of Transport Layer Security  The handshake is now finished, and the two hosts can communicate securely.
  • 22. Working of Transport Layer Security  To close the connection, a close notify 'alert' is used. If an attacker tries to terminate the connection by finishing the TCP connection (injecting a FIN packet), both sides will know the connection was improperly terminated. The connection cannot be compromised by this though, merely interrupted Ok. Gtg bye.. Ok see you later. TC
  • 23. Benefits of TLSSSL  Encryption  TLS can help to secure transmitted data using encryption.  Interoperability  TLS works with most Web browsers, including Microsoft Internet Explorer and Netscape Navigator, and on most operating systems and Web servers.  Algorithm flexibility  TLS provides options for the authentication mechanisms, encryption algorithms, and hashing algorithms that are used during the secure session.  Ease of deployment  Many applications use TLS transparently on a Windows Server 2003 operating systems.  Ease of use  Because you implement TLS beneath the application layer, most of its operations are completely invisible to the client.
  • 24. Govt municipal degree college Faisalabad

Editor's Notes

  1. The first difference is the version number (major and minor). The current version of SSL is 3.0; the current version of TLS is 1.0. In other words, SSLv3.0 is compatible with TLSv1.0. Another minor difference between SSL and TLS is the lack of support for the Fortezza method. TLS does not support Fortezza for key exchange or for encryption/decryption. “standardized” by IETF RFC2246.