NETWORK SECURITY

Network Security

Abstract

Network security is a paradoxical expression. The enormous network of networks which is very well known as the Internet is multifaceted, and as we know it is open for all. As many of us might have observed, without those main features in place, there would be no Internet. But with both present, we should understand that there can not be any perfect security, particularly since there are millions of people on the Internet who have a concentration in make the most by exploring its flaws for simple enjoyment, for criminal or theft purposes, or even for fighting war through this medium. The paper explores the computer and network security in depth.

Network Security

Introduction

Network security threats take several forms. First, there are hackers, computer-savvy individuals using their skills to break into computer networks to steal or alter data, or simply to experience the thrill of virtual cat-burglary. Next, there are viruses, destructive programs designed to attach to system files or other handy files in a computer; a virus lies dormant until the file is accessed, and then executes its destructive functions. Third, there are worms, powerful programs that usually gain access to computers through the Internet—often through email, sometimes by Web browsing. Many operate autonomously, but some, like the famous Internet Relay Chat-based PrettyPark worm, are executed only on the command of a hacker. Once worms infect a terminal, they usually seek other computers on the Internet to infect. Some worms, like the email-driven Code Red, have been known to cause many millions of dollars in damage, especially to corporations experiencing expensive down time and the destruction of valuable equipment and data.

Exploring the History of Network Security

Security has been an issue almost as long as there have been networked computers. In 1980, John Shoch and Jon Hupp of Xerox Palo Alto Research Center (PARC) in California created the first malicious worm by accident. Their idea was for the worm, as they called it, to automatically install Ethernet performance-measurement tools on 100 PARC computers, so the duo wrote a program capable of sending and installing itself across Xerox's closed network. However, as Robert Lemos recounted for CNET in March 2001, the program contained a bug, and bad code spread to each computer. Each time a terminal would install the worm, it would start to run, then crash the computer. Before long, Shoch and Hupp had rendered 100 Xerox computers useless.

In 1987, the first worm hit a public network, the IBM-only Internet precursor known as BITNET. The “Christmas Tree virus” drew a picture of a Christmas tree on an infected computer's screen before mailing itself to other computers. It eventually clogged IBM's entire international network.

In 1988, 23-year-old Cornell University graduate student Robert Morris wrote a worm that exploited “sendmail” flaws in the UNIX operating system. Like Shoch and Hupp, however, Morris wrote inadvertent bugs in the worm's code that caused it to propagate much faster than intended, according to Tangled Web author Richard Power. The Cornell worm spread rapidly, overloading between 3,000 and ...