… Babel can use IPv6 nexthops for IPv4 destinations - which is super useful because it will allow me to retire all of the IPv4 /31 point to point networks between my routers. AS8298 has about half of a /24 tied up in these

In contrast to legacy congestion control protocols that rely on loss as the primary signal of congestion, DCTCP signals in-network congestion (based on queue occupancy) to senders and adjusts the sending rate proportional to the level of congestion. At the time of our deployment, this protocol was well-studied and fairly established with proven efficiency gains in other networks. As expected, we also observed improved performance, and notably decreased packet losses, compared to legacy protocols in our data centers.