In the past decades, computer networks were primarily used by the researches for sending e-mails and by corporate employees for sharing the printers. While using network systems for theses utilities, security was not a major threat and did not get the due attention.
In today’s world computer networks gained an immensely and cover a multitude of sins. It covers simple issues like sending hate mails. Security problems also are very severe like stealing the research papers of the recent discoveries and inventions by the scientists, who use internet as a sharing tool, also hacking the financial products like credit cards, debit cards, bank accounts etc by hacking the passwords and misusing the accounts.
Cryptography is the ancient science of encoding messages so that only the sender and receiver can understand
them. Cryptography can perform more mathematical operations in a second than a human being could do in a lifetime. Within the context of any application-to-application communication, there are some specific security requirements. There are three types of cryptographic schemes. They are:
1. Secret Key Cryptography (SKC)
2. Public Key Cryptography (PKC)
3. Hash Functions
A basic understanding of computer networks is requisite in order to understand the principles of network security. The Internet is a valuable resource, and connection to it is essential for business, industry, and education. Building a network that will
connect to the Internet requires careful planning.Even for the individual user some planning and decisions are necessary. The computer itself must be considered, as well as the device itself that makes the connection to the local-area network (LAN), such as the network interface card or modem. The correct protocol must be configured so that the computer can connect to the Internet. Proper selection of a web browser is also important
What Is A Network?