Hacker packs 537,000 ad-blocking domains into $5 ESP32 dongle using clever hashing

Egyptian developer ZedAxis built a hardware-based DNS ad-blocker using a $5 ESP32-C3 SuperMini microcontroller. By employing 40-bit FNV-1a hashes, he compressed over 537,000 blocked domains into just 4MB of flash memory. The firmware uses only 50KB of RAM and answers blocked DNS lookups in about 10 milliseconds. The device serves as a backup ad-blocker for a home network, activating when the primary Pi-hole is unavailable. It can be powered from a USB port on an ISP gateway. The project sacrifices over-the-air firmware updates to maximize domain storage, and offers a rudimentary dashboard without detailed per-client statistics. The creator describes the cost as $2, though the board typically sells for around $5.

First published Aug 4, 01:52 PM UTCUpdated Jul 19, 10:00 AM UTC1 reports · 1 sources

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Hacker packs 537,000 ad-blocking domains into $5 ESP32 dongle using clever hashing

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Hacker packs 537,000 ad-blocking domains into $5 ESP32 dongle using clever hashingLatest from Tom's HardwareWesternJul 19, 10:00 AM UTC

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