Network Security 
S/MIME & E-mail Security 
Prafull Johri 2011BTechCSE007 
Pritam Kalwaniya 2011BTechCSE008 
Yogesh Chaube 2011BTechCSE014 
Shiva Johari 2011BTechCSE015
Why E-mail Security 
??? 
The Internet is an expansive network of 
computers, much of which is unprotected 
against malicious attacks. From the time an 
email composed to the time it is read, an email 
travels through this unprotected Internet, 
exposed to various electronic dangers.
What is E-mail Privacy 
The protection of email from unauthorized 
access and inspection is known as electronic 
privacy. In countries with a constitutional 
guarantee of the secrecy of correspondence, 
email is equated with letters and thus legally 
protected from all forms of eavesdropping.
Remedies 
 To provide a reasonable level of privacy, all 
routers in the email pathway, and all 
connections between them, must be secured. 
 At the ISP level, a further level of protection can be 
implemented by encrypting the communication 
between servers themselves, usually employing an 
encryption standard called Transport Layer 
Security (TLS). It is coupled with Simple 
Authentication and Security Layer (SASL), which 
confirms the target router's identity.
Remedies (contd.) 
O E- Mail encryption 
Email encryption can rely on public-key cryptography, in 
which users can each publish a public key that others can 
use to encrypt messages to them, while keeping secret a 
private key they can use to decrypt such messages or to 
digitally encrypt and sign messages they send.
PRETTY GOOD PRIVACY 
(PGP)
It is a remarkable phenomenon 
PGP provides a confidentiality and 
authentication service that can be used for 
electronic mail and file storage applications. 
• Selected the best cryptographic algorithms as building 
blocks 
• Integrated these algorithms to a general purpose 
application that is independent of operating system and 
processor, and is based on a small set of easy to use 
commands 
• Made the package and its documentation, including the 
source code, freely available via the Internet, bulletin 
boards, and commercial networks such as AOL
S/Mime 
O It is a security enhancement to the MIME 
Internet e-mail format standard, based on 
technology from RSA Data Security. 
RFC 822
RFC 822 
O It defines a format for text messages that 
are sent using electronic mail 
O It has been the standard for internet 
based text mail message and remains in 
common use
Mime is an extension to the RFC 822 framework that is 
intended to address some of the problems and limitations of 
the use of SMTP and RFC 822 foe e-mail. 
O SMTP cannot transmit executable files or 
other binary objects 
O SMTP cannot transmit text data that includes 
national language characters 
O SMTP servers may reject mail message over 
a certain size 
O and many more…..
S/MIME Functionality 
O Enveloped Data: This consist of encrypted content of 
any type and encrypted content encryption keys for one or 
more recipients 
O Signed Data: A digital signature is formed by taking the 
message digest of the content to be signed and then 
encrypting that with the private key of the signer.
S/MIME & E-mail Security (Network Security)

S/MIME & E-mail Security (Network Security)

  • 1.
    Network Security S/MIME& E-mail Security Prafull Johri 2011BTechCSE007 Pritam Kalwaniya 2011BTechCSE008 Yogesh Chaube 2011BTechCSE014 Shiva Johari 2011BTechCSE015
  • 2.
    Why E-mail Security ??? The Internet is an expansive network of computers, much of which is unprotected against malicious attacks. From the time an email composed to the time it is read, an email travels through this unprotected Internet, exposed to various electronic dangers.
  • 3.
    What is E-mailPrivacy The protection of email from unauthorized access and inspection is known as electronic privacy. In countries with a constitutional guarantee of the secrecy of correspondence, email is equated with letters and thus legally protected from all forms of eavesdropping.
  • 4.
    Remedies  Toprovide a reasonable level of privacy, all routers in the email pathway, and all connections between them, must be secured.  At the ISP level, a further level of protection can be implemented by encrypting the communication between servers themselves, usually employing an encryption standard called Transport Layer Security (TLS). It is coupled with Simple Authentication and Security Layer (SASL), which confirms the target router's identity.
  • 5.
    Remedies (contd.) OE- Mail encryption Email encryption can rely on public-key cryptography, in which users can each publish a public key that others can use to encrypt messages to them, while keeping secret a private key they can use to decrypt such messages or to digitally encrypt and sign messages they send.
  • 6.
  • 7.
    It is aremarkable phenomenon PGP provides a confidentiality and authentication service that can be used for electronic mail and file storage applications. • Selected the best cryptographic algorithms as building blocks • Integrated these algorithms to a general purpose application that is independent of operating system and processor, and is based on a small set of easy to use commands • Made the package and its documentation, including the source code, freely available via the Internet, bulletin boards, and commercial networks such as AOL
  • 8.
    S/Mime O Itis a security enhancement to the MIME Internet e-mail format standard, based on technology from RSA Data Security. RFC 822
  • 9.
    RFC 822 OIt defines a format for text messages that are sent using electronic mail O It has been the standard for internet based text mail message and remains in common use
  • 11.
    Mime is anextension to the RFC 822 framework that is intended to address some of the problems and limitations of the use of SMTP and RFC 822 foe e-mail. O SMTP cannot transmit executable files or other binary objects O SMTP cannot transmit text data that includes national language characters O SMTP servers may reject mail message over a certain size O and many more…..
  • 12.
    S/MIME Functionality OEnveloped Data: This consist of encrypted content of any type and encrypted content encryption keys for one or more recipients O Signed Data: A digital signature is formed by taking the message digest of the content to be signed and then encrypting that with the private key of the signer.