Dammit! I read from the wrong column for 1960-1962 data. The correct values are:

For 1960-1962 ages 18-79 (tables 1 and 2): 50th percentile male height is 68.3 inches (173.5 cm) and 166 pounds (75.5 kg). The 50th percentile female height is 62.9 inches (160cm) and 137 pounds (62.3 kg)

So the change in 50th percentile from 1960-1962 to 2015-2018 is +0.8 inches and +27 pounds for men and +0.6 inches and +24 pounds for women.

The CDC publishes survey data for the size of Americans. I was looking through the data a few days back purely out of idle curiosity.

From CDC 1960-1962, for ages 18-64 the 50-th percentile man was 68.6 inches (174 cm) and 157 pounds (71 kg). While the 50-th percentile woman was 63.9 inches (162 cm) and 126 pounds (57 kg).

From CDC 2015-2018, for ages 20+ the 50-th percentile man was 69.1 inches (175 cm) and 193 pounds (87.4 kg). While the 50-th percentile woman was 63.5 inches (161 cm) and 161 pounds (73.1 kg).

So, over that time median American men grew half an inch and 36 pounds and American women shrank by a bit under half an inch and gained 35 pounds. Clearly something is going on. I haven't seen more recent data than 2018, but I expect the trend to continue.

I have used ZFS as my file system for years using ZFS Boot Menu and it is great. The boot loader natively supports current versions of ZFS and you can roll-back to prior snapshots, clone your system, recover from backups, etc. I manually take a snapshot before any upgrades, but that could easily be automated.

It's a shame the ZFS license conflicts with the GPL. That means the GRUB is stuck with an old version of ZFS. If you use GRUB, you are forced to have two separate pools; an old version for booting and a newer version for the rest of the system. If you upgrade the boot pool, GRUB won't be able to read it and your system won't boot!

They can save a lot of time and money by producing only one label: TERRIFYINGLY INSECURE* *riddled with more holes than bad guys in a Rambo movie

Exposing root login over SSH to the internet is to be avoided unless you have no other option. A WireGuard VPN is great here becuase it won't respond to packets that don't authenticate.

I used to use OpenVPN for remote connections on TCP port 443. I thought it was clever since it looked like HTTPS traffic and would not be blocked by some random hotel's network connection when I traveled. However, I quickly learned that there are many bots that attempt to connect to TCP port 443. My OpenVPN server was constantly dealing with failed TLS connections. I tired banning IP address for a while, but they keep coming from new addresses. I had constant activity.

So, now my router drops all external connections except valid WireGuard packets. It won't even respond to pings. Everything of interest happens inside the WireGuard VPN. If you don't have one of the accepted keys, it looks like a disconnected IP address.

Of course, a directed DoS attack would still hurt but my life is easier with this approach.

The mirror solved a problem cameras had 60-70 years ago. It used to be you had to pick between one of three main options for a camera design:

• 1. Look through the lens with the shutter open to see what it was pointing at. Then close the shutter, put the film in the camera, and take the picture. (e g. view cameras)
• 2. Use a separate viewing port to see where the camera is pointed and optionally where it is focused. (Leica et. al.)
• 3. Have two lenses: one for the film, one to see what the camera is pointed at. (e. g. Rollei TLR)

The mirror in the SLR (Single Lens Reflex) allowed you to look through the lens that you take the picture with while keeping the viewfinder and film separate. This eliminated the parallax issues with range-finder cameras and allowed you to see depth of field without needing to use film holders or detachable film backs. It did require good alignment between the mirror and the film (or sensor) plane for the auto-focus to be precise. High-end SLRs had the ability to custom tune this for individual lenses to keep the focusing accurate.

Mirrorless cameras that use the sensor for the viewfinder solve all the issues above. At first they had high latency, low resolution, and limited dynamic range. However, Sony largely solved those issues with the A7 in 2013. Nikon and Canon had to wait until the advantages were so strong to be worth changing their existing product line. This is a large investment for them, but if they don't make it they can join Kodak wherever they are now.

There are two reasons to use an SLR camera today:

• 1. You have a large investment in an SLR system and it is not worth it to change yet.
• 2. Nostalgia. The same reason to use a view camera, TLR, range-finder, etc.

5 dimensions, eh? This sounds a bit familiar.

If you want to replicate Silicon Valley, people need to be able to move around and start their own companies. Employee non-compete agreements are void in California. They are enforceable with some limitations in Florida. Even if you ultimately win, the threat of legal action will prevent people from trying new things. Sure Silicon Valley has a lot of stupid start-ups, but some of those crazy ideas turn into great ideas. Onerous non-competes lets entrenched companies dominate.

Of course, stealing trade secrets is always illegal. However, a vibrant and fractious employment economy is part of what makes (made?) Silicon Valley an innovation hub.

While it is important to be able to learn how things work beneath the surface, most people only see the interface presented by whatever technology they use. As the technology matures, these interfaces become more opaque and removed from the underlying mechanics. For example, how many people can explain where the energy comes from that make the room bright when you press the switch on the wall. There are many layers there and most people will never know or care what they are.

I can imagine complaints from an earlier generation of proffessors:

Students these days have no idea how data is stored on drives! They simply type 'cp file1 file2' in a terminal and the bits move as if by magic.

From an even earlier generation:

Bits! You don't even know measure the magnetization of a substrate.

and further:

You can't begin to understand computing until you master the physics of vacuum tubes, you insensitive clod!

and so on...

P.S. The interfaces of modern software (phones, web, etc.) seems to develop an intuition that is in opposition to how things actually work. Maybe this is OK and maybe it isn't, but it means that casual users will be clueless to anything beyond the simple UI metaphors.

If we're talking about living long and accumulating the wisdom of ten generations, count me in. However, if what's on the table involves floating in space after the sun becomes a planetary nebula, count me out.

While not directly related to hacking, this was partly addressed in Executive Order 13920 which banned equipment and investment in the bulk-power system from foreign adversaries. Enforcement of this was suspended in section 7 (c) buried in Executive Order 13990 that was the high profile EO that stopped the KeystoneXL pipeline project.

For those not interested in reading the full EOs, there is a FAQ on the DOE website.

I considered various cloud providers, but ultimately decided that the convenience wasn't worth giving up control of my data. Maybe that's paranoid, but it I wanted ultimate control of my own data. Here is what I use:

1. NAS available to all computers at home. I mostly use SMB since it is the most consistent across Linux, Windows, and Mac clients. Anything important goes on the NAS.
2. The current generation of the NAS uses a 4-drive RIADZ2 ZFS pool with automatic snapshots. This can withstand two drive failures without loss of data. This is mainly so that we maintain redundancy while replacing a drive.
3. The last 14 daily and 12 monthly snapshots are replicated on an external backup drive. Periodically, we swap the external drive with one off site.

The key to this is that it is automated. Anything on the NAS gets snapshotted and backed up with cron jobs, I don't have to manually manage it. The only manual part is the off site drive swap.

BTW, for the latest generation of our NAS I splurged and got the Airtop 3. It is a bit spendy, but is awesome as a server that has to live in the same room as people. I use it as NAS + VM server. I am running a slimmed down debian stable with ZFS on root where the ZFS pools on the server are automatically snapshotted and backed up as well.

Mostly, commercial Unix is what killed commercial Unix. It was a fractured market where expensive custom OSes ran expensive custom software on expensive custom hardware. Linux was a breath of fresh air but big name Unix servers lost because the were punishing their customers. You had to sell your soul and commit to SGI, DEC, HP, or Sun. Good Riddance.

Haven't we seen this before?

It depends on where you are. Working at Big Tech in Silicon Valley can pay $200k+. But if you want to live there, you had better be willing to spend money on a house .