NMDC protocol: the original Direct Connect

NMDC is the original Direct Connect protocol from the NeoModus days. It is text-based, grew organically, and is messy in spots. A lot of it was reverse-engineered by the community, because there was no clean official spec for years. Sniff the traffic and you will see commands like $MyINFO, $Search, $ConnectToMe, and $ADCGET. NMDC later gained TLS encryption (NMDCS).

Documentation

• NMDC protocol documentation (updated by Aleksandr Zenkov, 2026)
• Older NMDC documentation (no longer updated)

See also the modern successor, the ADC protocol.