intrusion detection system
An intrusion detection system (IDS) inspects all inbound and outbound network activity and identifies suspicious patterns that may indicate a network or system attack from someone attempting to break into or compromise a system.
There are several ways to categorize an IDS:
- misuse detection vs. anomaly detection: in misuse detection, the IDS analyzes the information it gathers and compares it to large databases of attack signatures. Essentially, the IDS looks for a specific attack that has already been documented. Like a virus detection system, misuse detection software is only as good as the database of attack signatures that it uses to compare packets against. In anomaly detection, the system administrator defines the baseline, or normal, state of the network��s traffic load, breakdown, protocol, and typical packet size. The anomaly detector monitors network segments to compare their state to the normal baseline and look for anomalies.
- network-based vs. host-based systems: in a network-based system, or NIDS, the individual packets flowing through a network are analyzed. The NIDS can detect malicious packets that are designed to be overlooked by a firewall��s simplistic filtering rules. In a host-based system, the IDS examines at the activity on each individual computer or host.
- passive system vs. reactive system: in a passive system, the IDS detects a potential security breach, logs the information and signals an alert. In a reactive system, the IDS responds to the suspicious activity by logging off a user or by reprogramming the firewall to block network traffic from the suspected malicious source.
Though they both relate to network security, an IDS differs from a firewall in that a firewall looks out for intrusions in order to stop them from happening. The firewall limits the access between networks in order to prevent intrusion and does not signal an attack from inside the network. An IDS evaluates a suspected intrusion once it has taken place and signals an alarm. An IDS also watches for attacks that originate from within a system.
IT Solutions Builder TOP IT RESOURCES TO MOVE YOUR BUSINESS FORWARD
Which topic are you interested in?
What is your company size?
What is your job title?
What is your job function?
Searching our resource database to find your matches...
Stay up to date on the latest developments in Internet terminology with a free newsletter from Webopedia. Join to subscribe now.
From A3 to ZZZ this guide lists 1,500 text message and online chat abbreviations to help you translate and understand today's texting lingo. Read More »Top Cloud Computing Facts
The following facts and statistics capture the changing landscape of cloud computing and how service providers and customers are keeping up with... Read More »
Java is a high-level programming language. This guide describes the basics of Java, providing an overview of syntax, variables, data types and... Read More »Java Basics, Part 2
This second Study Guide describes the basics of Java, providing an overview of operators, modifiers and control Structures. Read More »Network Fundamentals Study Guide
Networking fundamentals teaches the building blocks of modern network design. Learn different types of networks, concepts, architecture and... Read More »