⚠️ Browser Limitations: This is a browser-based approximation. Results are affected by: (1) Browser connection limits (6-10 per domain), (2) JavaScript timing precision (~1ms), (3) CORS restrictions preventing raw socket access, (4) Single-threaded execution, (5) Memory and GC constraints. This implementation uses best-effort parallel connections, statistical smoothing, and high-resolution timers for realistic measurements within browser constraints. For authoritative results, use native CLI tools like iperf3 or system utilities.