E-commerce is the vehicle that allows a consumer to navigate by means of the Internet to a merchant's web site. There, the consumer decides what goods or services to purchase, and is then routed to an online transaction server, where all of the information provided is encrypted. The diversification of the Internet and expansive capability to assist the efforts of E-commerce is predicated on the safety and integrity of information being shared. This electronic connectivity must provide ways of protection and prevent the tampering or reading of important information. This responsibility is eased by an encryption technique. One of the several techniques for ensuring privacy of files and communications is Cryptography. Web security is a complex topic, encompassing computer system security, network security, authentication services, message validation, personal privacy issues, and of course cryptography.
There are two kinds of cryptosystems: symmetric and asymmetric. Symmetric cryptosystems use the same key (the secret key) to encrypt and decrypt a message, and asymmetric cryptosystems use one key (the public key) to encrypt a message and a different key (the private key) to decrypt it. Asymmetric cryptosystems are also called public key cryptosystems.
Cryptography is the science of encoding information into a form that is unreadable and making sure only the intended individuals are capable of decoding the information back into its original form. This is usually done by using an encryption algorithm and a decryption algorithm (these two are often the same) and very often a secret key. Some of the early cryptographic systems did not use a key but instead kept the algorithm itself secret. The message sender uses the encryption algorithm and the key to encode the message, and then sends it to the receiver. The receiver then uses the decryption algorithm and the key to turn back the encrypted information into its original form and read it.
