Construction of DDOS Denial of Service Attack Defense System

In the event of a DDOS Denial-of-Service attack on a website, the second step is to determine the type of DDOS attack in the methods used by EeSafe to help the website solve the problem.

The current website security alliance will be divided into the following three types of denial-of-service attacks:

 1. upgraded and changed SYN Attacks

This type of attack is most effective for websites that provide services based on ports. It can be said that it can kill network services of various server operating systems. The principle is to use a botnet to send a large number of spoofed source IP addresses + Source Port SYN packets to WebSite Services. The same is true for the upgraded and transformed ACK attacks, it also sends a large number of forged source IP address + Source Port ACK packets to the website service to exhaust website server resources and thus cannot provide normal services.

 

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2. TCP full connection attack

Most websites of some scale are installed with software or hardware firewalls. These firewalls are generally used to filter attacks such as teardrop and land, but they are allowed for normal TCP connections. However, for web servers such as IIS and Apache, the number of Tcp connections is limited. Once a large number of TCP connections exist, website access may be very slow or DoS attacks may occur. Tcp full-connection attacks use zombie hosts and website servers to establish a large number of tcp connections, resulting in depletion of server resources.

 

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3. script-based attacks

Almost every website has a list or information query function. These functions are used slowly and consume server memory. Script attacks are officially used, find the function points that consume server resources, and use several proxies to send a large number of requests that consume resources to the website server, so that the server resources are exhausted and the service is denied.

This is the classification of common DDOS denial-of-service attacks by the website security alliance. When we can determine which type of attacks we are under, we can well plan and build a defense system in the future, defend against DDOS attacks in the shortest time

Author: EeSafe Author: http://www.eesafe.com/bbs/thread-546-1-1.html