NetHang - Network quality simulation(weak network, network impairment)

NetHang is a web-based network quality simulation built on Linux. It is designed for simulating those annoying real-world network issues—like latency, packet loss, jitter or bandwidth limitation. It’s perfect for testing real-time communication apps, like video conferencing or live streaming, and even AI software that needs to interact with large models over the internet and also you can use NetHang for checking how well the congestion control algorithms or link stability hold up. Unlike other tools NetHang is focused on getting you realistic and reliable test results. Now, you might be thinking, “Aren’t there already tools like Linux TC/Netem, Apple’s Network Link Conditioner, or Tencent’s QNET?” Yep, there are, but here’s why NetHang is different—and honestly, better for internet products. First, cross-platform consistency. A lot of tools, like Network Link Conditioner, QNET or Clumsy, only work on specific platforms, making it hard to use the same testing standards across. NetHang? It runs as a service on a Linux soft router, so it delivers the exact same network impairment to any device connected through it. No more inconsistent results! Second, built-in network models. Most weak network tools throw a ton of confusing parameters at you—like packet loss, jitter, delay, reordering, you name it. For example, setting a 50ms jitter sounds simple, but does it really mimic real-world conditions? What about packet reordering? Delay distribution? It’s overwhelming, and honestly, most testers end up guessing. NetHang solves this problem by including pre-built, realistic network models based on actual network data. These models are constantly updated, so you’re not wasting time testing scenarios that don’t even happen in the real world. And third, custom dynamic network models. Last-mile networks—like your home Wi-Fi or mobile data—are super unpredictable. Different devices, signal strengths, and competing traffic make things messy. NetHang lets you create custom network conditions using simple YAML syntax, so you can simulate dynamic, real-time network changes that match what your users actually experience. So, why did I build NetHang? It all comes down to one big problem: most weak network tools focus on how to test, but not what to test. They give you a mountain of parameters—like jitter, packet loss, or bandwidth limits—that aren’t intuitive. For most engineers, it’s tough to know what settings actually make sense for real-world scenarios. Too often, people end up “guessing” and testing unrealistic conditions, like 1000ms jitter with reordering. Not only is that a waste of time, but over-optimizing for those cases can hurt your app’s performance elsewhere. NetHang flips the script by prioritizing what to test, offering realistic models and customizable options to make your testing smarter, not harder.