This is a great way to detect non-tail losses, and should definitely be a part of TCP implementations. I hope this gets turned into an RFC and pushed through th

This is a great way to detect non-tail losses, and should definitely be a part of TCP implementations. I hope this gets turned into an RFC and pushed through the standards process and widely deployed. I do hesitate a bit about Google calling it a "new loss detection algorithm" and talking about how "the key innovation in RACK is to use a per-packet transmission timestamp." The same approach was previously described by Sprout in 2013, and I'd bet by a lot of other people before that. ("The assumption underlying this method is that while the network may reorder packets, it will not reorder two packets that were sent more than 10 ms apart. Thus, once the receiver actually gets a packet from the sender, it can mark all bytes (up to the sequence number of the first packet sent within 10 ms) as received or lost, and only keep track of more recent packets." https://www.usenix.org/system/files/conference/nsdi13/nsdi13-final113.pdf https://www.usenix.org/system/files/conference/nsdi13/nsdi13...) The IRTF awarded this one of their Applied Networking Research Prizes that year, so it's not like it was totally just on the academic plane. Which is not to say Google isn't making 90% of the important contribution by measuring and documenting how valuable this is in real life, defining and implementing it in the context of TCP, standardizing it, getting an RFC, etc. It's just not quite as new as the I-D seems to suggest.