What is DDoS defense? Explanation of core concepts and protection principles

at the moment of rapid development of digital business, network attacks have become a major hidden danger to the stable operation of enterprises. Among them, Distributed Denial-of-service frequently causes paralysis to various network services by virtue of its large-scale attack and strong concealment. In order to help enterprises and individuals clearly understand the response plan of such attacks, this paper will disassemble the core logic of DDoS defense system from basic concepts, protection principles to landing means to make a comprehensive interpretation, so that readers can quickly grasp the key points of building a secure network environment.

What is the core concept of DDoS defense?

to do a good job of DDoS defense, we must first clarify its core definition and protection objectives, which is the basis for understanding the subsequent protection logic.

1, basic definition of DDoS defense

DDoS defense refers to a series of technical and management means to resist the distributed distributed Denial-of-service cyber security measures. Such attacks control a large number of puppet devices, send a large number of invalid requests to the target server or network node, and exhaust the target's bandwidth, computing power and other resources, making it impossible to provide services to legitimate users. The core goal of DDoS defense is to identify and intercept malicious traffic and ensure the normal passage of legitimate requests.

2, DDoS defense

DDoS defense covers the whole link from the network access layer to the application layer, not only to deal with traffic-based attacks against bandwidth, but also to deal with protocol-based attacks against specific application protocols, and resource-exhaustion attacks against business logic. There are differences in attack characteristics at different levels, which also requires the DDoS defense system to have the ability of layered protection.

What are the core protection principles of DDoS defense?

DDoS defense can effectively resist attacks, the core lies in its underlying protection principle based on traffic identification and resource scheduling, which is the technical core of the entire protection system.

1, abnormal flow recognition principle

this is the first step of DDoS defense, by establishing a baseline model of normal traffic and comparing the characteristics of real-time traffic to identify malicious requests. Common identification dimensions include traffic source IP distribution, request frequency, data packet format, protocol compliance, etc. Once the characteristics of a certain type of traffic deviate from the baseline and exceed the normal fluctuation range, it will be marked as abnormal traffic and enter the subsequent interception process.

2, flow cleaning and scheduling principle

identify abnormal traffic, DDoS defense will peel malicious traffic from the overall traffic and intercept it through traffic cleaning technology, and guide legitimate traffic to normal service nodes through intelligent scheduling systems. Some advanced DDoS defense solutions will also use traffic traction technology to direct attack traffic to a special cleaning center for processing, so as to avoid attack traffic directly reaching the target server.

What are the common implementation methods of DDoS defense?

master the specific implementation means of DDoS defense, we can transform the protection principle into practical security measures and build a practical protection system.

1, network layer DDoS defense means

network layer DDoS defense is mainly aimed at traffic-type attacks. Common means include bandwidth expansion, black hole routing and traffic cleaning. Bandwidth expansion can increase the upper limit of network bearer, black hole routing can direct attack traffic to invalid addresses, and traffic cleaning can identify and filter malicious data packets through professional equipment to ensure the normal transmission of legitimate traffic.

2, application layer DDoS defense means

application layer DDoS defense targets attacks launched using HTTP, HTTPS and other protocols. Common methods include CAPTCHA verification, session token verification, and rate limiting. CAPTCHA verification can distinguish between human-machine requests, session token verification can identify forged request sessions, and rate limiting prevents malicious requests from exhausting the resources of the application server by controlling the request frequency of a single IP.

4. Key points for enterprises to deploy DDoS defense?

enterprises to deploy DDoS defense is not a simple pile of technical means, need to combine their own business characteristics, grasp the key points of deployment in order to achieve efficient protection.

1, pre-assessment of DDoS defense

before deploying DDoS defense, enterprises need to complete the baseline assessment of business traffic and anticipate attack risk. By counting the characteristics of business traffic in different time periods, the fluctuation range of normal traffic is clarified, and the types of attacks that may be faced are analyzed in combination with business types. For example, e-commerce platforms are vulnerable to application layer attacks, while Cloud as a Service may face large traffic bandwidth attacks.

2, DDoS defense system

enterprises need to build a layered linkage DDoS defense system, combining network layer protection, application layer protection and traffic monitoring system to achieve full-link protection from traffic access to business response. At the same time, it is necessary to establish an emergency response mechanism. When encountering large-scale attacks, it can quickly switch protection strategies and link resources such as operators and security service providers to minimize attack losses.

sum up, DDoS defense is a multi-layered and multi-link cyber security system, which is closely related to each link from the cognition of the core concept to the implementation of the protection principle, and then to the actual deployment of the enterprise. By mastering the identification and cleaning logic of DDoS defense, and choosing the appropriate implementation means in combination with business characteristics, enterprises can build an effective protection barrier to resist the threat of distributed Denial-of-service and ensure the stable operation of digital business.