What is DDoS Attack and Why Need to Defend DDoS Attacks?
DDoS is arguably one of the most ferocious and difficult cyber-attacks to defend against. The reality is that there are few perfect and complete DDoS attack protections to this world-class problem, but it is necessary to take appropriate measures to reduce the impact and damage of an attack.
Considering DDoS defense as an important part of the overall security Policy, it is also indispensable to protect against DDoS attacks and thus prevent data leakage, malicious implantation, anti-virus protection, and other security measures.
How to Protect against DDoS Attacks?
First of all, DDoS attack protections are a systematic project, and it is silly and naïve to achieve a home run just by relying on a certain operation and a certain service, just like preventing a flu, you need to dress warmly, pay attention to your diet, and strengthen your exercise. According to the actual situation such as the size of the attack traffic, we can flexibly respond to the actual situation, adopt a variety of combinations, and customize policies to better achieve the defense effect. After all, attacks are all popular to take a hybrid route, how can defense still be a kung fu all-rounder.
Second, since DDoS attacks and defenses are facing costs, when our defense intensity gradually increases, the cost of attacks will also rise, and when most attackers can’t sustain and choose to give up, then the defense is considered successful. Therefore, we need to understand that defense measures and anti-D services are only a “mitigation” therapy, not a “cure” solution, and we talk about defense by taking corresponding measures to reduce the impact of DDoS attacks on enterprise business, rather than completely eradicating DDoS attacks.
Top 10 DDoS Attack Protections
Based on the above, we will talk about some basic measures, defense ideas and service plans to defend against DDoS attacks from three aspects (network facilities, defense solutions, and prevention methods).
Protect from DDoS Attacks by Network Equipment and Facilities
Network architecture, facilities and equipment is the hardware foundation for the smooth operation of the whole system, with enough machines, capacity to withstand attacks, making full use of network equipment to protect network resources is a more ideal coping Policy, in the final analysis, attack and defense is also a competition of resources between the two sides, in it continues to access users, seize user resources, their own energy is gradually depleted. Correspondingly, the investment is not small, but network facilities are the foundation of all DDoS attack protections, and you need to make a balanced choice according to your own situation.
1. Hard Resistance to Bandwidth Expansion
Network bandwidth directly determines the ability to withstand attacks, most of the domestic website bandwidth scale in 10M to 100M, well-known enterprises bandwidth can exceed 1G, more than 100G is basically specialized in bandwidth services and anti-attack services of the website, the number is only a handful. But DDoS is different, the attacker becomes a broiler by controlling some servers, personal computers, etc., if you control 1000 machines, each with a bandwidth of 10M, then the attacker has 10G of traffic. When they launch an attack on a website at the same time, the bandwidth is filled up in an instant.
Increasing bandwidth hard protection is the theoretical optimal solution, as long as the bandwidth is greater than the attack traffic, you are not afraid, but the cost is also unbearable, the bandwidth price of the computer room in non-first-tier cities in China is about 100 yuan/M* month, and the top of buying 10G bandwidth is 1 million, so many people ridicule that fighting bandwidth is fighting RMB, so that few people are willing to spend a high price to buy large bandwidth for defense.
2. Use a Hardware Firewall
Many people will consider using a hardware firewall, which is designed for DDoS attacks and hacker intrusions, and can resist SYN/ACK attacks, TCP full-connection attacks, script brushing attacks, and other traffic-based DDoS attacks by cleaning and filtering abnormal traffic. If your website is plagued by traffic attacks, you can consider placing your website in a DDoS hardware firewall room. However, if the website traffic attack exceeds the protection range of the hard defense (for example, the hard defense of 200G, but the attack traffic has 300G), the flood will not be able to resist the high wall. It is worth noting that some hardware firewalls are based on packet filtering firewall modifications, which only inspect packets at the network layer, and if DDoS attacks rise to the application layer, the defense capability is relatively weak.
3. Choose High-performance Equipment
In addition to firewalls, the performance of network devices such as servers, routers, and switches also needs to keep up. On the premise of network bandwidth guarantee, the hardware configuration should be improved as much as possible.
Effective Anti-D Ideas and Programs about DDoS Attack Protections
The hard-hitting defense is more “reckless”, and the behavior of improving the load capacity of the network through architecture layout, integrating resources, distributing local overloaded traffic, and identifying and intercepting malicious traffic by accessing third-party services is more “rational” and has a good confrontation effect.
1. Load balancing
The ability of a normal-level server to process data is limited to a maximum of hundreds of thousands of link requests per second. Load balancing is built on top of the existing network structure, which provides a cheap, effective and transparent way to expand the bandwidth of network devices and servers, increase throughput, strengthen network data processing capabilities, improve network flexibility and availability, and is effective against DDoS traffic attacks and CC attacks.
CC attacks overload servers due to the large amount of network traffic that is usually generated for a single page or link. After adding the load balancing solution to the enterprise website, the link requests are evenly distributed to each server, reducing the burden on a single server, and the entire server system can handle tens of millions or more service requests per second, and the user access speed will be accelerated.
2. CDN traffic scrubbing
CDN is a content distribution network built on the network, relying on edge servers deployed in various places, through the distribution and scheduling of the central platform, so that users can obtain the content they need nearby, reduce network congestion, and improve user access response speed and hit rate, so CDN Load balancing technology is also used. At present, most CDN nodes have 200G traffic protection function, coupled with hard protection, it can be said that it can cope with the vast majority of DDoS attacks.
3. Distributed cluster defense
If a node is attacked and cannot provide services, the system will automatically switch to another node according to the priority setting and return all the attacker’s data packets to the sending point, so that the attack source becomes paralyzed, and affects the security execution decision of the enterprise from a more in-depth security protection perspective.
Prevention is the Main Guarantee DDoS Attack Protections
The occurrence of DDoS can never be predicted, and it can be as ferocious as a flood bursting a levee, so it is especially important to take precautions and contingency plans for websites. Through daily inertial operation and maintenance, the system is robust and stable, and there are no vulnerabilities to drill, reducing the possibility of vulnerable services being compromised, and minimizing the losses caused by attacks.
1. Screen for system vulnerabilities
Early detection of system attack vulnerabilities, timely installation of system patches, establishment and improvement of backup mechanisms for important information (such as system configuration information), and careful setting of passwords for some privileged accounts (such as administrator accounts) can minimize the opportunities of attackers through a series of measures.
The Computer Emergency Response Coordination Center found that almost every system that was hit by a DDoS attack was not patched in a timely manner. Statistical analysis shows that many attackers have a high degree of success in attacks against organizations, not because of how sophisticated their tools and techniques are, but because the infrastructure they are attacking is inherently fraught with vulnerabilities.
2. System resource optimization
Optimize the system reasonably, avoid the waste of system resources, reduce the number of processes that the computer executes as much as possible, change the working mode, remove unnecessary interruptions to make the machine run more efficiently, optimize the file location to make data read and write faster, free up more system resources for users to use, and reduce unnecessary system add-ons and self-start items, and improve the load capacity of the web server.
3. Filter unnecessary services and ports
In the same way that thieves need to close and seal off redundant doors and windows, it is important to minimize the number of open ports in order to reduce the chance of attackers entering and exploiting known vulnerabilities and banning unused services. The port filtering module allows users to use or prohibit the use of some services by opening or closing some ports, filters data packets, analyzes ports, determines whether it is a port that allows data communication, and then processes accordingly.
4. Restrict specific traffic
Check the source of access and make appropriate restrictions to prevent abnormal and malicious traffic from coming, restrict specific traffic, and proactively protect the security of the website.
Conclusion
Fighting DDoS attacks is a multi-layered problem, and DDoS attack protections require not only a defense plan, a device, but also a team that can break and an effective mechanism. We’ve all heard the saying – God helps those who help themselves. Therefore, in the face of attacks, everyone needs to have security awareness and improve their own security protection system.
With the increasing abundance of Internet services, it is foreseeable that DDoS attacks will increase significantly, and the attack methods will become more and more sophisticated. Safety is a long-term and continuous work, which requires constant vigilance and the joint efforts of the whole society.