DST is the Datagram Stream Transfer protocol. In principle it's yet another way to provide a reliable stream protocol on top of UDP, similar to uTP, RUDP, and DST.
In fact, it's mostly based on DST with some significant differences;
The packet format is simplified.
The keepalive mechanism has been removed to reduce complexity and bandwidth use. Applications can perform keepalives as desired.
Windowing and congestion control is simpler, with room for future improvement.
There's currently no protocol specification document apart from the code. One will be written once it's proven to work and the formats can be locked down.
The API follows the usual
net conventions and should be familiar.