I'm currently looking into networking on Linux and and have found articles about various qdiscs. HTB is among them and as I have read, there are at least 3 versions of HTB, the third version having the best performance as tested on luxik.cdi.cz/~devik/qos/htb/htb3perf/cbqhtb3perf.htm . My question is whether this version is implemented in the newest kernel by default in the iproute2 package or if it uses the older versions and it needs to be added manually to the kernel? Cheers in advance.