Unpreventable Network Attacks - DDOS

DDoS (Distributed Denial of Service Attack) is a network attack. The attacker utilizes a large number of computers or network devices to send a large number of requests to the target server, making the target server unable to respond normally to requests from legitimate users,anti DDOS resulting in unavailability of services or degradation of service quality.

DDoS attack is characterized by the attacker can use a distributed way to launch the attack, the attack traffic is huge, the target of the attack is usually a large Internet technology service providers, e-commerce sites, financial management institutions, government agencies, etc.virtual Machine cloud The purpose of the DDoS attack is usually for extortion, political and educational purposes, retaliation and so on.

The principle of DDoS attack is to use a large number of computers or network devices to send a large number of requests to the target server, so that the target server can not properly respond to legitimate user requests.vpshosting Attackers usually use Botnet, which means that the attacker infects a large number of computers or network devices with malware, so that these computers or network devices become the attacker's control nodes, and the attacker can send a large number of requests to the target server through the control nodes.

The main types of DDoS attacks are as follows.

1.SYN Flood Attack: The attacker sends a large number of SYN requests to the target server, which makes the target server unable to respond to legitimate user requests.

2.UDP Flood attack: the attacker sends a large number of UDP requests to the target server, so that the target server can not respond to legitimate user requests.

3. ICMP Flood attack: the attacker sends a large number of ICMP requests to the target server, making the target server unable to respond to legitimate user requests.

4. HTTP Flood attack: The attacker sends a large number of HTTP requests to the target server, making the target server unable to respond to legitimate user requests.

5. DNS Amplification Attack: The attacker utilizes the vulnerability of the DNS server to send a large number of DNS requests to the target server, making the target server unable to respond to legitimate user requests.

The defense of DDoS attack mainly has the following kinds:

1. Traffic cleaning: Traffic cleaning refers to the filtering of network traffic through professional traffic cleaning equipment, which delivers legitimate traffic to the target server and filters out malicious traffic.

2. Load balancing: Load balancing refers to the dispersion of traffic management to multiple network servers by making each of our servers load balanced, which can improve the availability and stability of information systems.

3. Firewall: Firewall refers to the network access rules set up to filter and restrict network traffic, thereby protecting network security.

4. CDN Acceleration: CDN acceleration refers to the distribution of static resources of a website to multiple nodes, so that users can obtain resources from the nearest node, thus improving the access speed and stability of the website.

5. Restricted Access: Restricted access is defined as limiting access from a specific IP address or region by setting access rules to reduce the impact of malicious traffic.

If you can defend, why can't you defend against DDOS? Because DDOS itself is normal access, but someone maliciously using a large number of machines to access, resulting in server traffic load, defense methods are just sacrificing user traffic or increase server costs. In fact, it is also an unreasonable defense.

In short, DDoS attack is a network attack with a very dangerous way, for an enterprise and individuals are a threat. Therefore, we need to take effective defense measures to protect their network information security.