Engineering For Slow Internet Even When Not Stuck In Antarctica

September 5, 2025 by Maya Posch 25 Comments

With the days of dial-up and pitiful 2G data connections long behind most of us, it would seem tempting to stop caring about how much data an end-user is expected to suck down that big and wide broadband tube. This is a problem if your respective tube happens to be a thin straw and you’re located in a base somewhere in the Antarctic. Take it from [Paul Coldren], who was stationed at a number of Antarctic research stations as an IT specialist for a total of 14.5 months starting in August of 2022.

Prepare for hours of pain and retrying downloads. (Credit: Paul Coldren]

As [Paul] describes, the main access to the Internet at these bases is via satellite internet, which effectively are just relay stations. With over a thousand people at a station like McMurdo at certain parts of the season, internet bandwidth is a precious commodity and latency is understandably high.

This low bandwidth scenario led to highly aggravating scenarios, such as when a web app would time out on [Paul] while downloading a 20 MB JavaScript file, simply because things were going too slow. Upon timing out, it would wipe the cache, redirect to an error page and have [Paul] retry and retry to try to squeeze within the timeout window. Instead of just letting the download complete in ~15 minutes, it would take nearly half an hour this way, just so that [Paul] could send a few kB worth of text in a messaging app.

In addition to these artificial timeouts – despite continuing download progress – there’s also the issue of self-updating apps, with a downloader that does not allow you to schedule, pause, resume or do anything else that’d make downloading that massive update somewhat feasible. Another thing here is distributed downloads, such as when hundreds of people at said Antarctic station are all trying to update MacOS simultaneously. Here [Paul] ended up just – painfully and slowly – downloading the entire 12 GB MacOS ISO to distribute it across the station, but a Mac might still try to download a few GB of updates regardless.

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China Plans Its Own Megaconstellation To Challenge Starlink

June 22, 2023 by Lewin Day 39 Comments

Satellite internet used to be a woeful thing. Early networks relied on satellites in geostationary orbits, with high latency and minimal bandwidth keeping user demand low. That was until Starlink came along, and provided high-speed, low-latency internet access using a fleet of thousands of satellites in Low Earth orbit.

Starlink has already ruffled feathers due to concerns around light pollution and space junk in particular. Now, it appears that China may be readying its own competing constellation to avoid being crowded out of low orbits by the increasingly-popular service.

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The Great Euro Sat Hack Should Be A Warning To Us All

June 2, 2022 by Lewin Day 46 Comments

Military officials and civilian security researchers have been warning us for years: cyberattacks are becoming a very real part of modern warfare. Far from being limited to military targets, cyberattacks can take out everything from vital public infrastructure to commercial and industrial operations, too.

In the early hours of February 24, as the Russian invasion force began raining missiles on Ukrainian cities, another attack was in progress in the digital realm. Suddenly, satellite terminals across Europe were going offline, with many suffering permanent damage from the attack.

Details remain hazy, but researchers and military analysts have pieced together a picture of what happened that night. The Great Euro Sat Hack prove to be the latest example of how vulnerable our digital infrastructure can be in wartime.

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Starlink: A Review And Some Hacks

May 24, 2021 by Jonathan Bennett 129 Comments

I could probably be described as a SpaceX enthusiast. I catch their launches when I can, and I’ve watched the development of Starship with great interest. But the side-effect of SpaceX’s reusable launch system is that getting to space has become a lot cheaper. Having excess launch capacity means that space projects that were previously infeasible become suddenly at least plausible. One of those is Starlink.

Starlink is SpaceX’s satellite Internet service. Wireless and cellular internet have helped in some places, but if you really live out in the sticks, satellite internet is your only option. And while satellite Internet isn’t exactly new, Starlink is a bit different. Hughesnet, another provider, has a handful of satellites in geostationary orbit, which is about 22,000 miles above the earth. To quote Grace Hopper, holding a nearly foot-long length of wire representing a nanosecond, “Between here and the satellite, there are a very large number nanoseconds.”

SpaceX opted to do something a bit different. In what seemed like an insane pipe dream at the time, they planned to launch a satellite constellation of 12,000 birds, some of them flying as low as 214 mile altitude. The downside of flying so low is that they won’t stay in orbit as long, but SpaceX is launching them significantly faster than they’re coming down. So far, nearly 1,600 Starlink satellites are in orbit, in a criss-crossing pattern at 342 miles (550 km) up.

This hundred-fold difference in altitude matters. A Hughesnet connection has a minimum theoretical latency of 480 ms, and in reality runs closer to 600 ms. Starlink predicts a theoretical minimum of under 10 ms, though real-world performance isn’t quite that low yet. In the few weeks I’ve had the service, ping times have fallen from mid-60s down to 20s and 30s. The way Starlink works right now, data goes up to the closest satellite and directly back to the connected ground station. The long-term plan is to allow the satellites to talk directly to each other over laser links, skipping over the ground stations. Since the speed of light is higher in a vacuum than in a fiber-optic cable, the fully deployed system could potentially have lower latency than even fiber Internet, depending on the location of the endpoint and how many hops need to be made.

I got a Starlink setup, and have been trying out the beta service. Here’s my experience, and a bonus hack to boot.

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A Brief History Of Optical Communication

February 18, 2021 by Moritz v. Sivers 44 Comments

We live in the information age where access to the internet is considered a fundamental human right. Exercising this right does largely rely on the technological advances made in optical communication. Using light to send information has a long history: from ancient Greece, through Claude Chappe’s semaphore towers and Alexander Graham Bell’s photophone, to fiber optic networks and future satellite internet constellations currently developed by tech giants.

Let’s dive a little bit deeper into the technologies that were used to spread information with the help of light throughout history. Continue reading “A Brief History Of Optical Communication” →