This project does sound awesome and the release announcement is the first I'd heard of it.
However, there are a couple of issues. First, it appears that the patch set is no longer maintained. For the FreeBSD people out there, does inclusion in FreeBSD mean that that project has assumed the responsibility of porting the patches while they're needed, or should we just assume that FreeBSD 10 won't include the patches if a new SSH server comes out and the patches are not updated against it?
Also, this thread: http://lwn.net/Articles/377723 on LWN, containing input from an OpenSSH contributor (djm), claims that the HPN patches will not help until you are transferring at ~160Mbit/s @ 100ms lag and encourages normal users to benchmark the connection speed difference before assuming HPN will be faster for them. This is much higher than most anyone will get over the public internet, so should it be assumed that HPN is no longer necessary? Note also that thread is about OpenSSH 5.4. Have there been further improvements that have made the patchset even less necessary?
You raise some interesting points. 1) What makes it look like the project is no longer maintained? The latest patch release on the website is for 5.8p1 -- this is just 1 point beneath current (http://openbsd.org.ar/pub/OpenBSD/OpenSSH/portable/). 2) Great question. I would be interested in seeing the response this gets from the FBSD mailing list. 3) It is true that it is challenging (or rare) to get public internet speeds that will make HPN worthwhile, however I find HPN most useful on a LAN (typically within the same datacenter). I perform most of my data replication with rsync over HPN-SSH. It's multi-threaded and generally cuts CPU load over time. Thanks for linking to that thread over on LWN -- that was an interesting read.
I suppose "unmaintained" was incorrect, I probably should have said "not well maintained". I was going off of the notice on the HPN-SSH website at PSC: http://www.psc.edu/networking/projects/hpn-ssh/, which has a large bold header that repeatedly says that updates are "delayed" because all funding for the project is gone and there are no interested sponsors. So while not technically abandoned, the project is apparently "on the ropes" and further updates are questionable.
I usually use SSH on my local network too, but I usually max out the capacity of my disk in transfer speed anyway (gigabit network, but disk max read/write is ~30MB/s sustained), and there are definitely some fairly simple alternatives to local SSH usage if it's not fast enough in a particular situation (which I haven't encountered personally).
Of course, this doesn't mean HPN-SSH is useless, but its utility may manifest only in a small number of cases, making continued interest in maintenance or funding unlikely.
