High-defense IP is essentially an intermediate layer for traffic scrubbing and scheduling. Its core principle is not complex: it hides the real IP address of the website or server you need to protect, only publishing the high-defense IP address. All access traffic first arrives at the protection cluster where the high-defense IP resides, where it undergoes a rigorous "security check" process.
This process begins with anomaly detection. The system monitors hundreds of indicators in real time, such as traffic rate, packet characteristics, and connection request frequency, and compares them with a baseline of normal business traffic established by AI learning. It can identify anomalies within milliseconds. For example, a sudden surge of massive UDP packets from a highly concentrated source is likely a UDP Flood attack; while thousands of repeated requests per second to a specific API interface are characteristic of a CC attack.
After detecting an attack, the next step is traffic scrubbing. The scrubbing center uses various techniques to strip away malicious traffic. For network layer attacks (such as SYN Flood), mechanisms such as SYN cookies are used to verify connection authenticity and discard forged requests. For application-layer attacks, the capabilities of Web Application Firewalls (WAFs) are combined. These WAFs use CAPTCHA challenges, JavaScript fingerprinting, or frequency and behavior-based rules to precisely block malicious requests while allowing legitimate users to access the site. Major US service providers, such as AWS Shield Advanced and Google Cloud Armor, employ this type of collaborative protection strategy that deeply integrates with WAFs.
Ultimately, the "cleaned" legitimate traffic is forwarded to your real server via a secure origin-back link. Because the real IP address is hidden, attackers cannot directly attack your origin server, thus ensuring the security of core infrastructure.
How strong is the protection? The reality behind the numbers
US high-defense IP service providers typically promise powerful protection capabilities. Data shows that many services offer protection bandwidth at the Tbps (terabits per second) level. For example, OVHcloud claims up to 1.3Tbps of cleaning capability in the US, while some customized solutions can even scale to 2000Gbps. They can effectively defend against hundreds of attack types, including SYN Flood, UDP Flood, and HTTP Flood.
However, "Tbps-level protection" does not equal "unlimited protection." Each service provider has its own capacity limit, which is often directly related to your investment costs. For example, Tencent Cloud's documentation clearly states that its overseas DDoS protection IP's elastic protection is capped at 400Gbps. This means that if your business suffers an attack of up to 500Gbps, and your protection package's limit is 400Gbps, the excess traffic could potentially cause damage.
Attack methods are also constantly evolving. Today's DDoS attacks are often "hybrid attacks," meaning they launch multi-dimensional attacks simultaneously from the network, transport, and application layers. For example, attackers might use UDP floods to clog bandwidth while simultaneously using sophisticated CC attacks to simulate real users consuming server CPU and database resources. Single defense strategies are easily overwhelmed by such combined attacks; therefore, modern DDoS protection IPs must rely on a "defense-in-depth" system that integrates network layer scrubbing, perimeter WAF, and host layer protection. The advantage of solutions from major US cloud vendors lies precisely in this deep integration and collaboration within a cloud-native environment.
Limitations of DDoS Protection IPs: Which attacks might slip through the net?
Understanding the power of DDoS protected IPs is important, but recognizing their limitations is equally crucial. No security solution can guarantee 100% protection, and DDoS protected IPs are no exception. Their effectiveness is limited primarily in the following areas:
1. Direct attacks bypassing protection: The effectiveness of DDoS protected IPs relies on all traffic passing through them. If your server's real IP address is leaked due to management negligence, attackers can completely bypass the DDoS protected IP and directly attack the origin server, rendering all protection ineffective. Therefore, strictly protecting the origin server's IP and ensuring all access (including management access) passes through the DDoS protected IP or a dedicated channel is the absolute bottom line for effective protection.
2. Large-scale attacks and resource exhaustion: As mentioned earlier, when the attack scale exceeds the limit of your purchased DDoS protected IP package, the protection will be breached. Furthermore, even with application-layer CC attacks, if the remaining legitimate requests (or difficult-to-identify simulated requests) after "cleaning" the attack traffic surge, it may still exceed the processing capacity of your backend servers, leading to service slowdowns or crashes. This necessitates leveraging the cloud platform's auto-scaling capabilities to dynamically expand backend resources to handle traffic.
3. Emerging and Complex Attack Methods: Attack techniques are constantly evolving. For example, low-speed, slow-moving attacks targeting vulnerabilities in new protocols like HTTPS/HTTP/2 and WebSocket, or AI-driven attacks that highly mimic human behavior and constantly change characteristics, may initially bypass detection based on fixed rules and traditional AI models. Defending against these threats heavily relies on the service provider's speed of threat intelligence updates, the iterative capabilities of AI models, and the real-time response level of the security team.
4. Human Oversights in Configuration and Management: High-defense IPs provide tools and platforms; their effectiveness largely depends on the user's configuration. Improper blacklist/whitelist settings, overly lenient or stringent protection rules, and failure to adjust frequency thresholds according to business changes can all significantly reduce protection effectiveness. For example, Tencent Cloud documentation indicates that there is an upper limit to the number of blacklist/whitelist rules for a single high-defense IP instance.
Finally, high-defense IPs should be considered a core component of an enterprise's security system, not the entirety of it. It needs to be combined with a robust upstream network architecture (hiding the origin server), solid backend application security (code security, vulnerability management), and a comprehensive business continuity plan (multi-cloud disaster recovery, data backup). Regular security audits and simulated attack tests (must be conducted with the service provider's authorization) are essential to continuously validate and optimize your protection system.
