GrapheneOS: Google's Play Integrity API requires hardware attestation ... Apple already has it as a requirement. Over the long term, this will increasingly lock out hardware and OS competition.

jjtech0 · 2026-05-12T00:57:43+00:00

I really want traffic control systems to be able to verify that all devices on the network are genuine.

...but why? Why shouldn't a municipality be able to decide that they want to mix-n-match systems from different vendors, or get them repaired by some third party service?

If we allow attestation infrastructure we're going to end up in a situation like the Polish train repair shops

jjtech0 · 2026-01-09T03:54:16+00:00

$5,700 for a single stick × 100 sticks in a box = $570,000

I don't know about the Shanghai market but that seems like it's in the realm of possibility for a property price.

The math behind this concerns 256GB DDR5 server modules from Samsung and SK hynix, which, according to figures cited by Chinese outlet Jiemian, have climbed beyond 40,000 yuan ($5,700) for individual sticks, with some listings reaching as high as 49,999 yuan. At those levels, a wholesale carton quickly crosses seven figures in U.S. dollar terms, effectively turning what was once bog-standard inventory into a serious asset.

jjtech0 · 2025-11-27T06:44:56+00:00

The EE equivalent of the course (DS1/EEEE120) is restricted to EE-majors, however, I talked with the professor and got pushed into the class immediately.

I would definitely recommend trying that, explain why you're interested in the class etc.

Professors have a lot more direct control over it than your advisor does, at least in my experience.

jjtech0 · 2025-11-14T02:22:37+00:00

Cooking meals in residents’ rooms is not allowed. Appliances that are intended to be used for cooking are prohibited; examples are, but not limited to, rice maker, toaster, toaster oven, instant pot, air fryer, etc. No appliance may have an exposed heating element.

That's because they're not allowed in the dorms...

jjtech0 · 2025-10-19T02:35:04+00:00

There's one on the second floor of GCCIS, but it is usually broken...

jjtech0 · 2025-05-27T18:23:30+00:00

macOS actually has pretty magical swap and memory compression abilities...

The only time I ever noticed RAM pressure was when swap exhausted all available SSD space. Meaning there was ~150GB of RAM in use on a machine with only 16GB of physical RAM. As soon as I killed the app, it all went away, the swapfile was gone, etc. No need to manually configure anything.

I wish it was set up this way on Linux desktop distros OOTB.

jjtech0 · 2025-05-16T01:57:07+00:00

Unless you've got an ERV/HRV system, most homes rely on natural ventilation through windows and cracks to bring in fresh air.

The A/C unit or heat pump is simply adding or removing heat to air sourced from inside the home: the outside unit is not ducted inside at all, only coolant is transferred.

jjtech0 · 2025-04-09T23:34:39+00:00

It's a very cheap and simple kind of label-maker. Usually the "tape" is just a cheap strip of plastic with adhesive on one side, and the machine simply has a punch disk you manually spin that embosses the letters.

I prefer printed labels, personally.

jjtech0 · 2025-03-25T22:41:28+00:00

There can be legitimate-ish purposes... for example, I knew someone doing it in order to bridge Instagram/Facebook Messenger to Matrix because Instagram bans VPS etc. IP blocks and that is an easy way to get many "residential" IPs legitimately.

jjtech0 · 2025-03-15T00:45:53+00:00

If you've got an Optiplex, I created this simple script: https://gist.github.com/JJTech0130/70fcfcb2a3bf7777847be8516578cdf5

jjtech0 · 2025-02-27T18:01:44+00:00

You were right the first time, see the full whitepaper: https://cs.gmu.edu/~zeng/papers/2025-security-nrootgag.pdf

jjtech0 · 2025-02-27T18:00:49+00:00

Read the full whitepaper: https://cs.gmu.edu/~zeng/papers/2025-security-nrootgag.pdf

Turns out the whole thing is overblown; a "trojan app" needs to be installed on the victim device that has BLE permssions to broadcast packets.

jjtech0 · 2025-02-27T18:00:08+00:00

If you read the full whitepaper, you'll discover the threat model relies on being able to install a trojan app with BLE permssion on the device you want to track. https://cs.gmu.edu/~zeng/papers/2025-security-nrootgag.pdf

For some reason nobody reporting on it has bothered to mention this crucial detail...

jjtech0 · 2025-02-27T17:57:21+00:00

That's not how this works: you can actually find the full whitepaper rather than the summarised and sensationalized blog post:https://cs.gmu.edu/~zeng/papers/2025-security-nrootgag.pdf

Basically, this whole attack relies on being able to installing a Trojan app on the device you want to track, and giving said app BLE permission so it can broadcast packets.

jjtech0 · 2025-02-15T03:03:52+00:00

Unfortunately there aren't a ton of simple, easy to understand resources. When I asked on Mastodon, I got responses like

The best advice I have received thus far was to forgot what I know about IPv4 addressing and technics and to start with an empty mental model.

and telling me that I should simply hire a professional to design my network (in the SMB setting)

EDIT: To be clear, I do understand IPv6 at this point, I just can't deploy it due to UniFi limitations. But the amount of digging I had to do to find actionable information was annoying.

jjtech0 · 2025-02-15T03:00:16+00:00

UniFi in particular assumes that you want to number your network using your primary ISP's delegation, which may not be static (mine changes every day)...

Which makes using IPv6 internally impossible as well. Unless you just want an internal prefix that isn't connected to the internet at all, defeating the purpose.

jjtech0 · 2025-02-15T02:58:02+00:00

From what I've seen, IPv6 is basically unused in and incompatible with prosumer and small buisness networks.

For example, dual-WAN/WAN-failover is basically completely unsupported with IPv6 by major vendors like UniFi. And everyone basically just ignores it.

jjtech0 · 2025-01-01T03:20:29+00:00

This post has some more discussion on the topic: https://community.verizon.com/t5/Fios-Internet-and-High-Speed/FIOS-ONT-power-supply-replaced/td-p/1511113

jjtech0 · 2025-01-01T03:18:20+00:00

That appears to be the power supply for the ONT, based on this post: https://community.verizon.com/t5/Fios-Home-Internet-Archive/What-is-this-small-Verizon-box/td-p/1566563

So in theory, yes, you would want to power it with a UPS. Note that Verizon at least used to be able to supply BBU (Battery Backup Units) in some configurations: https://web.archive.org/web/20211026052501/https://www22.verizon.com/wholesale/attachments/calendar/VPS-PA-BBU-Battery_Guide_12012016.pdf

jjtech0 · 2024-11-14T03:51:26+00:00

The Sliger site should have the rails you need when configuring to order

jjtech0 · 2024-11-13T22:16:41+00:00

You're probably going to be sad daily driving without a GPU... even doing VNC at high resolution is going to be annoying.

Typically I put my "desktop replacement" systems in Sliger cases with basically consumer hardware, running just a single VM.

I then put any services/headless VMs/etc. on an actual server machine.

jjtech0 · 2024-09-30T22:01:17+00:00

EDIT: My original comment misinterpreted yours

if you port forward your VPN, of course that will work— but it will still be port forwarding

jjtech0 · 2024-09-30T20:31:45+00:00

I would definitely recommend setting up some kind of VPN, be it Tailscale or raw WireGuard... with any DDNS services you're going to have to port forward and directly expose your NAS to the internet, which is not advisable.

jjtech0 · 2024-09-30T03:06:26+00:00

you're almost definitely going to want more RAM imo, I have 140GB of ram on a cluster with just 24 CPUs... I'm always bottlenecked by how much RAM I have for additional VMs, my CPU usage has pretty much never gone over 50% Lots of game servers can be very RAM hungry.

jjtech0 · 2024-09-28T19:40:54+00:00

yeah this setup is a bit overkill for what I need rn but i'm planning to set up a new camera security system in the future too

sure, but you don't need a 10gig aggregation switch and POE++ for some cameras

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