It may not be the implementation you referred to, but https://github.com/savoirfairelinux/opendht https://github.com/savoirfairelinux/opendht exist and is used

It may not be the implementation you referred to, but https://github.com/savoirfairelinux/opendht https://github.com/savoirfairelinux/opendht exist and is used by the Ring distributed communication platform along with SIP (ring.cx) to implement the account less, P2P and PKI encrypted communication. (disclaimer, I have previously worked on Ring.cx)