IDS is an acronym for Intrusion Detection System. An intrusion detection system detects intruders; that is, unexpected, unwanted or unauthorized people or programs on my computer network.
Why do I need IDS? A network firewall will keep the bad guys off my network, right? And my anti-virus will recognize and get rid of any virus I might catch, right? And my password-protected access control will stop the office cleaner trawling through my network after I've gone home, right? So that's it - I'm fully protected, right?
Wrong!

This tutorial is a comprehensive guide to the features provided by the Nmap Port Scanner. It is meant as an introduction for new users, a reference on new and existing features for experienced users, and an FAQ list. It is not intended as a replacement for the Nmap Manual Page, but more as a supplement to it.

Cross-site scripting, often abbreviated XSS, is a class of Web security issues. A recent research report stated that XSS is now the top security risk.
In a typical XSS scenario, a Web page might use JavaScript to dynamically generate some document content based on a field in a Uniform Resource Identifier (URI). In the normal course of events, the site itself would generate legitimate information for that field.

The most common blunder people make when the topic of a computer virus arises is to refer to a worm or Trojan horse as a virus. While the words Trojan, worm and virus are often used interchangeably, they are not the same. Viruses, worms and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences among the three, and knowing those differences can help you to better protect your computer from their often damaging effects.

Ten Commandments to Protect your PC:

Please find below the ten best practices you can follow to protect your PC:

TOP Intrusion Detection Systems Interview Questions and FAQs:

Here is a list of the top intrusion detection systems frequently asked questions. This section is also a very good resource for preparation of job interviews for IDS.

What are events?

Events are actions that take place on the network. Examples of events might be a failed connection attempt, a connection established between two computers, a successful authentication and login, a Web browser requesting a URL, or the response sent back by the a Web server.

What are zero day attacks?

Zero-day exploits occur when an exploit for vulnerability is created before, or on the same day that a vulnerability becomes known to the world at large. IT organizations are constantly fighting to keep their systems patched and updated, but the reality is it takes time to adequately test a patch against all applications running on the servers. This leaves organizations exposed to the narrowing of the time between discovering a vulnerability and the time an exploit is launched. As such, an attacker can effectively compromise unprotected servers at will.