Do you want to prevent an attack on your site or server? Learn what is a DDoS attack and how does it work?
DDoS Attack Mitigation Introduction
A Distributed Denial-of-Service attack is an attempt to make an online service unavailable by overwhelming it with traffic from multiple sources. Also, it is a cyberattack that occurs when multiple computers (or systems) attack a single target such as a website, server, etc. So, it is an intentionally targeted attack via multiple computers that come from different sources.
Each computer (or system) in the botnet can send a part of the total traffic directed to the victim. Hence, the name “distributed” or “distributed denial-of-service” attack. The distributed nature of the attack makes it difficult to defend against and can result in effective denial of service to legitimate users.
How Does It Work?
DDoS attacks are generally not executed by one person alone, but by groups of people who use automated tools and instructions. This makes it easy for anyone to participate in these attacks. DDoS Attacks typically occur when bandwidth or resources exceed capacity.
This includes preventing legitimate users from accessing the site or service. DDoS attacks can be accomplished in several ways and can target any part of the network infrastructure where they are hosted. They are usually carried out through botnets.
These are networks of computers infected with malicious software and controlled as a group without the owners’ knowledge or consent. Also, a botnet operator can launch different types of DoS attacks through infected computers. So, a botnet’s control mechanism is usually based on IRC (Internet Relay Chat).
Typically, IRC is used for text messaging between members. But certain software clients can be exploited to issue commands to multiple systems at once via C&C channels (Command & Control). Such clients include “IRC bots” often used for automation purposes.
Instead of being controlled by text commands sent over IRC, victims can be controlled through other means. Such as e-mail messages containing malware that installs malware on their computers. So, software vulnerabilities or even physical access to their computers via USB flash drives.
Intrusion Prevention Assessment
A good way to protect against DDoS attacks is by having a failover backup server that can be switched online. This is in case the primary server becomes overwhelmed by requests. If the primary server goes down due to overwhelming traffic from server requests, the backup server can take over.
So this helps ensure continuity of service for legitimate users. Block all incoming connections from outside sources except those necessary for normal operations. Attackers use these connections to control their botnets.
Also, this access compromised computers running as zombies in their botnets. Blocking all incoming connections except those necessary for normal operations will limit the number of computers that a hacker can use for an attack. Another way to harden your network security against DDoS attacks is by blocking all packets.
Block those that are sent with invalid source IP addresses. Hence, this will ensure only valid packets are allowed into your network.