Tag: cryptography

Posted on by

Ancient Web: JProc Preserves the Strange History of TEMPEST

Computers can leak secrets without sending a packet.

Visit JProc’s TEMPEST page

The page collects material about compromising emanations: unintended electromagnetic or acoustic signals from information-processing equipment that can reveal what the machine is doing.

The history is wonderfully strange.

A declassified NSA account traces the problem back to World War II, when Bell Telephone engineers discovered that encrypted teletype equipment was radiating patterns correlated with the plaintext being processed. In a demonstration across the street from a Signal Corps crypto center, engineers were reportedly able to reconstruct much of the message from the leaked signal.

The machine was secure. The room was talking.

That is the conceptual punch of TEMPEST.

A cryptographic system can be mathematically strong while the hardware implementing it leaks information through a completely different channel.

The page follows the subject through Cold War countermeasures, intelligence collection, shielding standards, and later public research into display emissions. It also points to Wim van Eck’s 1985 work showing that information from computer monitors could be reconstructed with comparatively inexpensive equipment.

The site is not itself a modern security standard or operational guide. Its value is historical: it connects wartime teletype equipment, classified shielding programs, declassified NSA material, Cold War espionage, and the eventual public understanding that electronic devices radiate more than engineers intend.

That history matters because side-channel attacks are now a normal security concept. Timing, power use, sound, electromagnetic emissions, and other physical behavior can all betray information even when the cryptography is sound.

Old pages like this preserve how surprising that idea once seemed.

CacheRat’s 1,967 Ancient Web Domains research list includes many technical pages whose real value is contextual: they show when obscure specialist knowledge first escaped into the public web.

TEMPEST is a perfect example.

The secret was not necessarily in the cipher.

Sometimes it was humming out of the box.

Return to JProc’s TEMPEST page

Posted on by

Ancient Web: Crypto Museum Is an Entire Spy Museum Hiding in a Browser

Crypto Museum has the structure of an old specialist website and the inventory of a small intelligence museum. Click around long enough and you are suddenly reading wiring notes for obscure encryption equipment that probably spent most of its working life behind locked doors.

Visit Crypto Museum

Based in the Netherlands, Crypto Museum describes itself as a virtual museum backed by a real physical collection. Its purpose is preservation: historical cipher machines, Enigma equipment, spy radios, burst encoders, intercept receivers, covert devices, bugs, recording gear, codebreaking machines, telephones, telex hardware, radar, and the organizations and manufacturers behind them.

The index is enormous.

Individual equipment pages often combine photographs, technical descriptions, history, internal views, manuals, circuit information, accessories, variants, and references. A visitor can move from a famous Enigma machine into Cold War radio gear, concealed transmitters, telephone security devices, or a manufacturer that vanished decades ago.

It still behaves like a working collection

This is not an abandoned museum site preserved in amber. New items and rewritten pages were still appearing in 2026. The curators acquire equipment, restore it, identify unknown devices, add manuals, run events, and correct older material.

They also explicitly state that the site contains no cookies or trackers. That is almost aggressively on-brand for a cryptography museum.

The archive is especially useful because hardware preservation without documentation only gets you halfway there. A cipher machine behind glass tells you what it looked like. Manuals, wiring, context, model variants, operator accessories, and photographs of internal construction explain what the thing actually was.

The site is privately funded and says its curators aim to share as much information as possible. It is a good example of what specialist web publishing can accomplish when the people maintaining it care more about the collection than about pageviews.

Crypto Museum appeared in CacheRat’s larger Ancient Web research corpus.

Explore the 1,967 Ancient Web Domains research list

If your idea of a pleasant evening includes Enigma machines, Cold War bugs, strange radios, and declassified hardware, you have been warned.

Go back to Crypto Museum