|Subject||Computer and Network Security|
|NU Year||Set: 6.(a) Marks: 5*4 Year: 2014|
Product cipher, data encryption scheme in which the ciphertext produced by encrypting a plaintext document is subjected to further encryption. By combining two or more simple transposition ciphers substitution ciphers, a more secure encryption may result.
SSL (Secure Sockets Layer) 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. SSL is an industry standard and is used by millions of websites in the protection of their online transactions with their customers.
A hash function takes a group of characters (called a key) and maps it to a value of a certain length (called a hash value or hash). The hash value is representative of the original string of characters but is normally smaller than the original.
S/MIME, or Secure/Multipurpose Internet Mail Extensions, is a technology that allows you to encrypt your emails. S/MIME is based on asymmetric cryptography to protect your emails from unwanted access. It also allows you to digitally sign your emails to verify you as the legitimate sender of the message, making it an effective weapon against many phishing attacks out there.