Hacker fits 537,000 blocked domains on $5 ESP32 ad-blocking 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 half a million 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 for a primary Pi-hole, automatically taking over during reboots or outages. It can block up to 537,000 domains if over-the-air updates are disabled, or 250,000 with OTA enabled. The project demonstrates a practical, low-cost approach to network-level ad blocking using minimal hardware.

First published Aug 4, 01:55 PM UTCUpdated Jul 19, 10:00 AM UTC1 reports · 1 sources

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Hacker fits 537,000 blocked domains on $5 ESP32 ad-blocking dongle using clever hashing

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

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