How does a universal firewall protect against DDOS, does it depend on rules, policies, or whatever?

The attack characteristics, as well as the class addition of the attack, are implemented according to the principle of layers 3 to 5!

Firewalls provide perimeter access control by monitoring and tracking allowed network traffic, packets, and packets. In many ways, firewalls act as the "traffic police" of the network. It allows good, healthy packets to access the server unhindered, while preventing bad, abnormal packets from accessing the server's network.

Firewalls can help detect incoming malicious traffic, but they don't have much of a defense against incoming malicious traffic.

Many enterprise users who rent servers rely solely on firewalls to mitigate DDoS attacks. However, it only relies on hardware firewalls to defend against DDoS attacks, and the defense capability is generally within 30Gbps, and the service is expensive. These business users who use traditional firewalls to defend against DDoS attacks believe that firewalls can be updated, which can effectively prevent DDoS attacks.

However, this is not the case, and the firewall generally controls the flow of data in and out according to the rules pre-defined by the system administrator, which is either a piece of hardware or a set of software built on general hardware. Most firewalls do not have targeted improvements and designs for DDoS attacks, making it difficult to withstand and defend against large-scale and multiple types of DDoS attacks.

There are two main reasons for this:

1. Firewalls are limited by bandwidth and are easy to be breached.

Firewalls and other on-premises hardware have very limited bandwidth, including the scale of bandwidth that enterprises rent.

When the scale of DDoS attacks exceeds 20-30 Gbit/s, the bandwidth can quickly become overwhelming, and defenses will collapse.

2. Firewall rule management.

Firewall-defined rule management can sometimes be fooled by "malicious traffic" masquerading as legitimate normal traffic, like "syn flood" (a type of DDoS attack).

Therefore, it is more effective to provide deep packet and traffic inspection, adjust traffic cleaning rules in a targeted manner, and provide specific countermeasures to combat various types of DDoS attacks, which is more effective than the static operation of firewall rule management.

As a result, a firewall is only one part of a defense strategy, not a complete solution. If you want to defend against DDoS attacks more comprehensively and effectively, you must not only rely on firewalls, but also combine other technologies and devices to defend against them.

Anti-DDoS server, professional anti-DDoS attack, with the characteristics of "ultra-large protection bandwidth, super cleaning ability, and support for all business scenarios". In the Anti-DDoS server room where the Anti-DDoS Pro server is deployed, the defense bar is connected to T-level (1000G) ultra-large protection bandwidth, and the peak defense of a single machine (a single Anti-DDoS server) can reach up to hundreds of Gbit/s, and it is equipped with the defense capability of CC attacks, which can defend against ultra-large-scale DDoS attacks and high-density CC attacks.

This depends on the specific protection capabilities of the firewall you buy. Now many manufacturers are providing dead traffic, but it is very expensive, as long as you have money, you will definitely be able to prevent it.

Yes, but it depends on the ability and level.

Firewalls can't prevent DDoS attacks, DDoS just increases the number of visits, unless you don't let others access, when the traffic exceeds the server's network bandwidth, the server will be congested to the point of inaccessibility, that is, paralysis. The most common is the ping attack, and it is also the simplest, the defense ping attack is very simple, the server IP can be banned, and the ping can also be used to defend against other attacks, and the basis for whether some hackers stop the attack is whether your server is ping, because it also takes cost to launch a DDoS attack, requiring a large number of broilers, etc., it is impossible to continue to attack a target for a long time, unless it is targeted! The most fundamental way to defend against DDoS attacks can be usedWeike Cloud DDoS cloud cleaningThis cloud product features:

DDoS Cloud Cleaning provides customers with a safe and reliable protection service through the widely distributed cleaning centers of service providers around the world. DDoS Cloud Cleaning analyzes a large number of online attack data through the service provider's self-developed protection algorithm, and combines it with its global intelligent scheduling system for real-time detection, and then intelligently cleans various DDoS attacks at edge security nodes.

DDoS traffic attacks are attacks on a single machine by using controlled machines, so that the attacked host has no time to react, so this kind of attack will be more destructive. In the past, in order to fight against DDoS, network administrators would use the method of filtering IP ridges with addresses, but he could not do anything about forged addresses. Therefore, preventing DDoS attacks is not as simple as before, so how should we deal with it?

In the following, I will briefly introduce some small methods to defend against DDoS attacks.

1. Scan regularly.

Regularly scan the primary nodes of the network to find out vulnerabilities and deal with them in a timely manner. Backbone nodes all have high bandwidth and are also the best places for hackers to exploit, so the security of hosts on these nodes needs to be taken seriously.

2. Set up the attack-oriented target.

The firewall itself is used to protect the host, so it can defend against some attacks. Configure the corresponding sacrifice machine in the defense of attacks, and once it is found that it is attacked, it can directly direct the attack to those sacrifice hosts, so as to protect the real host from being attacked.

3. Adopt cluster defense.

By using cluster defense, the defense value of multiple hosts can be added together to jointly resist the attacks faced by a certain machine, which is also a better way to resist attacks, and can fully deploy the limited defense force and concentrate on defense.

4. Use network equipment for defense.

Network defense devices mostly refer to load balancing devices such as routers and firewalls, which can play a role in protecting the network. Along the attack path, when the network is attacked, the router is the first to be killed, but other devices will not be affected. When the attack is carried out on the next device, the previous device may continue to be resurrected and can be used normally.

It's also possible to defend against attacks through network devices. wxalm168888

1. Filter unnecessary services and ports: You can use tools such as InExpress, Express, and Forwarding to filter unnecessary services and ports, that is, filter fake IPs on the router.

2. Cleaning and filtering of abnormal traffic: Through the cleaning and filtering of abnormal traffic by the DDOS hardware firewall, through the rule filtering of data packets, the detection and filtering of data flow fingerprints, and the customized filtering of data packet content, it can accurately judge whether the external access traffic is normal, and further prohibit the filtering of abnormal traffic.

3. Distributed cluster defense: This is currently the most effective method for the network security community to defend against large-scale DDoS attacks. The feature of distributed cluster defense is that each node server is configured with multiple IP addresses, and each node can withstand no less than 10G DDoS attacks.

4. Anti-DDoS intelligent DNS resolution: The perfect combination of the high-intelligence DNS resolution system and the DDoS defense system provides enterprises with super detection functions to combat emerging security threats. It subverts the traditional practice of one domain name corresponding to one image, and can only resolve DNS resolution requests to the server of the user's network according to the user's Internet route.

At the same time, the intelligent DNS resolution system also has a downtime detection function, which can intelligently replace the paralyzed server IP with a normal server IP at any time, so as to maintain a service state that will never go down for the enterprise network.