Image by Luis Llerena Unsplash

Internet connections get faster but websites get more complex—and that means we often still have to wait an age for pages to load. Now, a new technique from MIT that helps browsers gather files more efficiently could change that.


“As pages increase in complexity, they often require multiple trips that create delays that really add up,” explains Ravi Netravali, one of the researchers, in a press release. “Our approach minimizes the number of round trips so that we can substantially speed up a page’s load-time.” The new system, known as Polaris, was been developed by the University’s at Computer Science and Artificial Intelligence Laboratory.

Loading a web page is an oddly complex business. Hit enter after a URL or click on a link and your browser busies itself gathering a series of objects—HTML files, JavaScript, pictures and who knows what else. Each object is evaluated, then added to the page you’re looking at. But that evaluation can result in having to fetch other, dependent objects—and browsers don’t know what those dependencies are until they’ve grabbed the first object. If they did, they’d be able to pull across more files in one go, reducing the amount of back-and-forth across the network, reducing the time it takes to load a page.


That’s where Polaris comes in. What it does is log all the dependancies and inter-dependancies on a web page. It compiles all of these into a graph for the page that a browser can use to download page elements more efficiently. The researchers liken it to the work of travelling salesperson:

When you visit one city, you sometimes discover more cities you have to visit before going home. If someone gave you the entire list of cities ahead of time, you could plan the fastest possible route. Without the list, though, you have to discover new cities as you go, which results in unnecessary zig-zagging between far-away cities... For a web browser, loading all of a page’s objects is like visiting all of the cities. Polaris effectively gives you a list of all the cities before your trip actually begins.

The team’s tested the the system on 200 different websites, including ESPN, Weather.com, and Wikipedia. On average, it was able to load web pages 34 percent faster than a standard browser. The work will be presented later this week at the USENIX Symposium on Networked Systems Design and Implementation.

The good news is that Polaris is written in JavaScript. That means that it could be introduced to any website—it’d just have to be running on the server in question, so it’d automatically kick in for any page load—and used with unmodified browsers.


But the long-term hope of the researchers is that it becomes integrated into the browsers we all use, where it could “enable additional optimizations that can further accelerate page loads.” We can’t wait.