NSFOCUS Anti-DDoS System (ADS) is a stateless DDoS mitigation appliance designed for service providers to protect against distributed denial of service attacks. The system removes malicious traffic while allowing legitimate traffic to pass through in real-time, eliminating the need for null routing. The solution consists of multiple components: the core ADS appliance for traffic scrubbing, Network Traffic Analyzer (NTA) for attack detection using flow monitoring with over 30 detection vectors, Anti-DDoS System Manager (ADSM) for centralized multi-tenant management with a customer portal, Magic Flow (MF) for network analysis and threat intelligence integration, Flow Load Balancer (FLB) for distributing traffic across multiple NTA devices, and Active Defense Business Operating System (ADBOS) for centralized management of on-premises devices and cloud services. The system provides mitigation capabilities up to 400Gbps across various performance-optimized appliances. It uses learning algorithms and threat intelligence to detect and mitigate both known and unknown DDoS attack types. The platform includes multi-stage detection engines, behavioral analysis, and automated mitigation capabilities. A web-based dashboard provides visibility into attack lifecycles and mitigation strategies. The solution supports flexible deployment models with scalable licensing that allows capacity expansion as needed.