Reverse engineering a Viking VOIP phone protocol with Claude Code
summary
A Viking VoIP phone sits in the ElevenLabs San Francisco office for a year and three senior engineers plus ChatGPT cannot get it working. Claude Code cracks the undocumented protocol in days: brute forced 676 two-letter commands, finds 80 valid commands, sets up a TCP proxy to log the proprietary Windows XP software, identifies a persistence sequence and reverse engineers a one-byte checksum subtraction, open sources the protocol as a Claude Code skill and the red phone booth demo works.
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chapters (14)
- 0:00Viking phone project intro
- 1:33Legacy hardware challenge
- 2:57Claude Code for reverse engineering
- 4:03Phone communication ports
- 6:12Brute-forcing command codes
- 7:41Memory persistence issues
- 9:06Windows VM with TCP proxy
- 10:33Protocol traffic analysis
- 12:21Checksum encryption cracked
- 13:04Phone memory storage reversed
- 14:30Key insights from process
- 15:54Extending to other hardware
- 16:37Demo and final outcome
- 17:18Q&A
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