A few months ago, I downgraded my internet, going from a 900Mbps plan to a 200Mbps one. Now, I find that websites can sometimes take a painfully long time to load, that HD YouTube videos have to stop and buffer when I jump around in them, and that video calls can be annoyingly choppy.
In other words, pretty much nothing has changed. I had those exact same problems even when I had near-gigabit download service, and I’m probably not alone. I’m sure many of you have also had the experience of cursing a slow-loading website and growing even more confused when a “speed test” says that your internet should be able to play dozens of 4K Netflix streams at once. So what gives?
Like any issue, there are many factors at play. But a major one is latency, or the amount of time it takes for your device to send data to a server and get data back — it doesn’t matter how much bandwidth you have if your packets (the little bundles of data that travel over the network) are getting stuck somewhere. But while people have some idea about how latency works thanks to popular speed tests, including a “ping” metric, common methods of measuring it haven’t always provided a complete picture.
The good news is that there’s a plan to almost eliminate latency, and big companies like Apple, Google, Comcast, Charter, Nvidia, Valve, Nokia, Ericsson, T-Mobile parent company Deutsche Telekom, and more have shown an interest. It’s a new internet standard called L4S that was finalized and published in January, and it could put a serious dent in the amount of time we spend waiting around for webpages or streams to load and cut down on glitches in video calls. It could also help change the way we think about internet speed and help developers create applications that just aren’t possible with the current realities of the internet.
Before we talk about L4S, though, we should lay some groundwork.
There are a lot of potential reasons. The internet is a
series of tubes vast network of interconnected routers, switches, fibers, and more that connect your device to a server (or, often, multiple servers) somewhere. If there’s a bottleneck at any point in that path, your surfing experience could suffer. And there are a lot of potential bottlenecks — the server hosting the video you want to watch could have limited capacity for uploads, a vital part of the internet’s infrastructure could be down, meaning the data has to travel further to get to you, your computer could be struggling to process the data, etc.
The real kicker is that the lowest-capacity link in the chain determines the limits of what’s possible. You could be connected to the fastest server imaginable via an 8Gbps connection, and if your router can only process 10Mbps of data at a time, that’s what you’ll be limited to. Oh, and also, every delay adds up, so if your computer adds 20 milliseconds of delay, and your router adds 50 milliseconds of delay, you end up waiting at least 70 milliseconds for something to happen. (These are completely arbitrary examples, but you get the point.)
In recent years, network engineers and researchers have started raising concerns about how the traffic management systems that are meant to make sure network equipment doesn’t get overwhelmed may actually make things slower. Part of the problem is what’s called “buffer bloat.”
Right? But to understand what buffer bloat really is, we first have to understand what buffers are. As we’ve touched on already, networking is a bit of a dance; each part of the network (such as switches, routers, modems, etc.) has its own limit on how much data it can handle. But because the devices that are on the network and how much traffic they have to deal with is constantly changing, none of our phones or computers really know how much data to send at a time.