Technical Architecture Comparison

SAST architecture revolves around sophisticated code analysis engines that parse, model, and analyze application code. These engines build abstract representations of programs—control flow graphs, data flow models, and call graphs—that enable vulnerability detection. Modern SAST tools employ multiple analysis techniques: pattern matching for simple vulnerabilities, taint analysis for injection flaws, and symbolic execution for complex logic errors. The architecture must handle various input formats (source code, bytecode, binaries) while maintaining accuracy across different programming languages.

IAST architecture focuses on runtime instrumentation and observation. Agents or sensors integrate with application runtime environments through various mechanisms: bytecode instrumentation for Java, CLR profiling APIs for .NET, or middleware hooks for interpreted languages. These sensors observe application behavior in real-time, tracking data flow, monitoring security operations, and identifying vulnerability patterns. The architecture must minimize performance overhead while capturing comprehensive security telemetry.

The architectural requirements create different scaling challenges. SAST must process potentially millions of lines of code efficiently, requiring powerful analysis servers and sophisticated caching mechanisms. IAST must operate within application processes without significantly impacting performance, demanding lightweight sensors and efficient data collection. These constraints shape tool capabilities and deployment options.