Onion routing disguises internet traffic in layers resembling a nesting doll

A US Department of Defense research lab developed the technology for the dark web

Although encryption existed to mask the content of communications across the internet before the 1990s, those managing overseas network infrastructure could determine a spy's affiliation based on where they saw data sent to and received from. To keep this information secret, the US Naval Research Laboratory developed onion routing, which enabled anonymized web browsing. The release of the technology to the public obscured sensitive communications further by growing the volume of anonymous data.

An explanation of TCP/IP, which helps transmit data across the internet like a club sandwich

The system consists of several layers—application, transport, internet, and network—each responsible for specific tasks. These include interacting with a web browser, checking for errors, sending packets of data across various networks to avoid congestion on their way to a destination address, and managing the transmission of information across hardware, such as an Ethernet cable.

Explore metrics on the Tor network, the infrastructure of the dark web

While internet traffic within the network is concealed, public, nonsensitive data can be used to estimate the number of active users, the number of relay servers, network performance speed and reliability, etc. Researchers can use this data to indirectly identify political upheavals or censorship campaigns worldwide, such as the Arab Spring.

Instead of .com or similar, web addresses on the dark web end in 'd.onion'

Since the latest version of the onion routing protocol, dark web domain names consist of a random set of 56 alphanumeric characters followed by .onion (e.g., propublica.org → p53lf57qovyuvwsc6xnrppyply3vtqm7l6pcobkmyqsiofyeznfu5uqd.onion). The last character is always "d" due to the encryption algorithm's requirements.

The 500 subsea cables that run the internet

Subsea cables carry the majority of data sent across the globe on the internet. An estimated 552 such cables—with more in development—lay on the ocean floor, their thickness similar to a garden hose, made up of optic fibers covered in copper.

A look at nodes and miners in managing bitcoin transactions

Each time a transaction involving bitcoin is carried out, the information must be relayed and recorded onto the currency’s blockchain. Multiple steps are involved, including the passage of the transaction to various nodes and miners who comprise multiple layers of verification and validation. See an illustrated guide to how these two crucial features of bitcoin processing work here.

Google data centers possess six layers of security

Property boundaries, such as anti-climb fencing, overlapping cameras, vehicle crash barriers, and circulating patrols, are coupled with lobby iris scans and ID and badge checks. The security operations center monitors individuals throughout their visit, including the less than 1% of Google users who ever receive permission to visit the data center floor.

Money laundering is a three-step process: placement, layering, and integration

"Placement" occurs when dirty money is introduced into the financial system. Then "layering" happens when the money is moved around to disguise where it actually came from. Finally, the money is placed in other assets or investments in a step called integration.

Learn how governments around the world restrict internet access for their citizens

Various countries around the world, including China, Russia, and Iran, control their local DNS infrastructure, allowing them to block access to online content by preventing the internet "phone book" from finding the IP addresses for specific URLs. Government-controlled internet service providers can also cut off access entirely or throttle specific traffic.

How end-to-end encryption protects messages, even from service providers

Using symmetric and asymmetric cryptography, data is encrypted on the sender's device before being transmitted across application servers that lack the key needed to decrypt it. The message is not decrypted until it reaches the recipient's device, which uses their private key to recover the plaintext. E2EE's effectiveness has led to its adoption by WhatsApp and Signal.

Create your own cipher by combining mathematical operations and encryption protocols

This tool allows users to build an encryption workflow in which the output of one customizable function becomes the input to another, thereby creating undiscovered methods for obscuring information via a series of ciphers.

Explaining how open source systems like Linux can be secure, despite their public source code

While no computer system is immune to all cyberattacks and malware, the transparency of open-source technology means many thousands of developers can review and oversee the underlying code powering the software on an ongoing basis. This increases the likelihood of catching and patching vulnerabilities more quickly than smaller groups of cybercriminals looking to exploit them.

The origin of shortest-path algorithms and how they became optimized for navigation apps

In 1956, Dutch programmer Edsger Dijkstra spent about 20 minutes developing an algorithm to demonstrate how computers could quickly determine the shortest route between Rotterdam and Groningen. Since then, modified versions of Dijkstra's formulation comprise the processing backbone of systems such as Google Maps and Apple Maps.

Ads follow you around the internet through cookies

A technology called “cookies” enables advertisers to essentially team up and follow your behavior around on the internet. This video explains why it seems like ads seem to follow you as you go from website to website—as well as data privacy advocates’ war against cookies.

Earth's inner structure is a dynamic system of layers in constant, slow motion

From the crust to the core, each of Earth's layers—some solid, some liquid—plays a role in generating its magnetic field, moving tectonic plates, and cycling matter. These details are determined through modeling since humans have only drilled 12 kilometers underground.

'The Great Onion Corner:' Hear how short-selling onions ended with a ban on onion futures

In the early 1950s, onion farmer and produce trader Vince Kosuga cornered the onion market, resulting in a 1958 ban on onion futures from Congress. After stockpiling onions and buying onion futures, Kosuga then began shorting them. Then, he released his accumulated surplus of onions, driving the price down to essentially zero, and cashed in his short positions.

The platform's ease of use relies on a complex architecture

Hitting "play" on Netflix is easy, but it triggers a multistep process that fetches the selected content, converts it for your screen, and finds the closest server to deliver it in the highest quality.

Pizzagate alleged a neighborhood pizza joint was hosting a sex trafficking scheme

During the 2016 presidential elections, Comet Ping Pong Pizza became the subject of a conspiracy theory that the Clinton family used the space as a front for kidnapping and trafficking children. The hoax began on the message board 4chan after the public became aware that the shop's owner was a Democratic donor.

Essential pipes, sewers, and cables lie buried beneath New York City

The Department of Design and Construction offers a tour of its work sites, explaining the complex systems that exist underground. Gas, electrical, telecom pipes, and many others, sprawl out underneath the entire city, with dozens of maps that help workers know where they're placed. This layout is unusual compared to the rest of the country, where wires are often present and visible above ground.

Trick an LLM into revealing sensitive information

Even with robust training, large language models may be fooled into providing sensitive information if correctly prompted. In this game, a wizard withholds eight passwords, which you must prompt them to reveal with ever-increasing LLM safeguards.

Microchips in payment cards improve security by generating unique transaction codes

Magnetic strips store unchanging data that is easily cloned, but microchips act as miniature computers that encrypt sensitive data. They also resist fraud by creating data unique to each transaction, preventing duplication.

Behind the fascinating disguising mechanism of camouflage

Camouflage—nature's master game of hide-and-seek—is more complex than simply how things look. The disguising process required millions of years of evolution that have programmed how our brains take shortcuts. Watch this video to see examples of camouflage and understand how we process it.

Visualizing the world's food supply chains

The world's food supply chain is complex and lopsided, with much of the world's nutrient-rich food ending up in Europe and North America. This visualization illustrates the paths our food takes around the world, from starchy vegetables in...

Breaking down how Dickinson viewed letters as an extension of her poetry

The poet's many correspondences were dashed with playful arrangements of text, offering her pen pals surprises once they opened their envelopes. Jana Dambrogio and Daniel Starza Smith explain how Dickinson even creatively used the 19th-century security technique of letterlocking in poetic ways.

Boost your Wi-Fi with aluminum foil

A surprising hack using aluminum foil can potentially improve Wi-Fi signals, to many readers' surprise. Check out the science with this brief article. Wi-Fi signals spread like radio or light waves from a router's antenna, often leading to...

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'

The idea for the Federal Reserve was conceived in secret in 1910—with bankers donning duck hunt gear for disguise while traveling to a remote country club on Georgia's Jekyll Island

Netflix profits when you're not watching, and its movies are designed that way—read a detail-rich critical essay exposing lesser-known Netflix takes

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

In 2019, a laptop loaded with six of the worst malware in history and described as 'an exhibit of historical weaponry' sold for $1.3M.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

During the French Revolution, a botanist's letter asking about "dear Rhus" (poison ivy) was intercepted, leading authorities to suspect he was conspiring with the Russians.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

Ebola infects and disables immune cells, triggering a cascade of events that leads to small blood clots throughout the body, weakening blood vessels and interrupting blood flow to key organs.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

Explore fun facts from the USPS, including unique post office buildings, a stamp that traveled past Pluto, and more.

US intelligence allegedly pursued more than 600 schemes to assassinate Cuban revolutionary Fidel Castro.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

Read a deep dive on the 'all-purpose healing' peptide BPC-157.

Neutron stars, the remains of some massive stars after they explode in a supernova, are the densest directly observable objects in the universe.

Up to a million Girl Scouts sell about 200 million cookie boxes every spring, generating $800 million, largely because refusing a child is frowned upon

An initial public offering or 'IPO' is the process of a private company becoming public by putting shares of the company on the stock market for purchase.

Georgia O'Keeffe's flower paintings are often assumed to be sexual, though the artist claimed she was simply interested in highlighting the beauty of flowers that most people neglect

Play the role of a student in a game where you try to navigate college and remain debt-free, selecting different income levels, high school experience, race, ethnicity, and more.