ISAE-SUPAERO ENAC ISAE-SUPAERO INRIA This document is a product of the Coding for Efficient Network Communications Research Group (NWCRG). It conforms to the directions found in the NWCRG taxonomy [RFC8406] . This document describes Tetrys, an On-The-Fly Network Coding (NC) protocol that can be used to transport delay and loss-sensitive data over a lossy network. Tetrys can recover from erasures within an RTT-independent delay, thanks to the transmission of coded packets. It can be used for both unicast, multicast and anycast communications.