Secure Socket Layer, or SSL, is a cryptographic protocol that provides security for communications over networks such as the Internet.
SSL is used in combination with the Hypertext Transfer Protocol (HTTP) to become what is known as HTTPS or Hypertext Transfer Protocol Secure. SSL is used beyond the HTTP though – there are several versions of the protocol for applications like email, internet faxing, instant messaging and voice-over-IP.
SSL and other cryptographic protocols ensure that communications between client and server in a network are safe from eavesdropping and tampering. This is done through a communication method between a client and server following a very well-defined set of steps or protocol of handshaking, encryption and decryption of information packets.
In applications utilizing SSL, such as web browsing, the communication between the client and the server is secured and encrypted. By encrypting the information that is transmitted, it cannot be read or modified by other nodes who might be listening in the network.
The value of SSL in web browsing is underlined in pages that require that the user inputs like passwords, identification numbers, credit card information and other sensitive and critical information. By using HTTPS (HTTP + SSL), the user is assured that any information that is sent to the server is protected and cannot be read by anyone else but the server.
SSL is important in e-commerce because of the sensitivity of financial information transmitted in transactions, such as purchasing using credit cards or other online payment methods.