Entering The Wild World Of Power Over Ethernet

October 11, 2025 by Maya Posch 50 Comments

As Ethernet became the world-wide standard for wired networking, there was one nagging problem. You already have to plug in the network cable. But then you have to also plug in a power cable. That power cable needs to be long enough. And have the right plug on it for your country. And provide the right current and voltage. That’s how Power over Ethernet (PoE) was born, first in a veritable Wild West of proprietary standards and passive injectors, then in a standardized process. Recently [T. K. Hareendran] wrote a primer on PoE, with more of a DIY intro focus, including some favorite PoE PD (powered device) chips to use in your own design.

You can still totally use passive PoE if that’s your jam, and you have full control over the network and any connected devices. This would allow you to, for example, power your SBCs for a couple of bucks, although for adding PoE to your Mac Mini you may want to look at some more refined options, if only as a safety precaution.

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QUIC! Jump To User Space!

October 10, 2025 by Al Williams 19 Comments

Everyone knows that Weird Al lampooned computers in a famous parody song (It’s All About the Pentiums). But if you want more hardcore (including more hardcore language, so if you are offended by rap music-style explicit lyrics, maybe don’t look this up), you probably want “Kill Dash 9” by Monzy. There’s a line in that song about “You thought the seven-layer model referred to a burrito.” In fact, it refers to how networking applications operate, and it is so ingrained that you don’t even hear about it much these days. But as [Codemia] points out, QUIC aims to disrupt the model, and for good reason.

Historically, your application (at layer 7) interacts with the network through other layers like the presentation layer and session layer. At layer 4, though, there is the transport layer where two names come into play: TCP and UDP. Generally, UDP is useful where you want to send data and you don’t expect the system to do much. Data might show up at its destination. Or not. Or it might show up multiple times. It might show up in the wrong order. TCP solves all that, but you have little control over how it does that.

When things are congested, there are different strategies TCP can use, but changing them can be difficult. That’s where QUIC comes in. It is like a user-space TCP layer built over a UDP transport. There are a lot of advantages to that, and if you want to know more, or even just want a good overview of network congestion control mitigations, check the post out.

If you want to know more about congestion control, catch a wave.

Meshtastic: A Tale Of Two Cities

October 9, 2025 by Tom Nardi 81 Comments

If I’m honest with myself, I don’t really need access to an off-grid, fault-tolerant, mesh network like Meshtastic. The weather here in New Jersey isn’t quite so dynamic that there’s any great chance the local infrastructure will be knocked offline, and while I do value my privacy as much as any other self-respecting hacker, there’s nothing in my chats that’s sensitive enough that it needs to be done off the Internet.

But damn it, do I want it. The idea that everyday citizens of all walks of life are organizing and building out their own communications network with DIY hardware and open source software is incredibly exciting to me. It’s like the best parts of a cyberpunk novel, without all the cybernetic implants, pollution, and over-reaching megacorps. Well, we’ve got those last two, but you know what I mean.

Meshtastic maps are never exhaustive, but this gives an idea of node density in Philly versus surrounding area.

Even though I found the Meshtastic concept appealing, my seemingly infinite backlog of projects kept me from getting involved until relatively recently. It wasn’t until I got my hands on the Hacker Pager that my passing interest turned into a full blown obsession. But it’s perhaps not for the reason you might think. Traveling around to different East Coast events with the device in my bag, it would happily chirp away when within range of Philadelphia or New York, but then fall silent again once I got home. While I’d get the occasional notification of a nearby node, my area had nothing like the robust and active mesh networks found in those cities.

Well, they say you should be the change you want to see in the world, so I decided to do something about it. Obviously I wouldn’t be able to build up an entire network by myself, but I figured that if I started standing up some nodes, others might notice and follow suit. It was around this time that Seeed Studio introduced the SenseCAP Solar node, which looked like a good way to get started. So I bought two of them with the idea of putting one on my house and the other on my parent’s place down the shore.

The results weren’t quite what I expected, but it’s certainly been an interesting experience so far, and today I’m even more eager to build up the mesh than I was in the beginning.

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A Lorenz Teletype Shows Us Its Secrets

October 7, 2025 by Jenny List 23 Comments

When we use the command line on Linux, we often refer to it as a terminal. It’s a word with a past invoking images of serial terminals, rows of green-screened machines hooked up to a central computer somewhere. Those in turn were electronic versions of mechanical teletypes, and it’s one of these machines we’re bringing you today. [DipDoT] has a Lorenz teletype from the 1950s, and he’s taking us through servicing and cleaning it, eventually showing us its inner workings.

The machine in question had been in storage for many years, but remained in good condition. To be this long out of use though meant it needed a thorough clean, so he sets about oiling the many hundreds of maintenance points listed in a Lorenz manual. It’s a pleasant surprise for us to see keyboard and printer unit come away from the chassis for servicing so easily, and by stepping it through its operation step by step we can see how it works in detail. It even incorporates an identifier key — think of it as a mechanical ROM that stores a sequence of letters — which leads him to believe it may have come from a New York news office. The video is below the break, and makes for an interesting watch.

He’s going to use it with a relay computer, but if you don’t have one of those there are more modern ways to do it.

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Using The 74HC595 Shift Register To Drive 7-Segment Displays

August 21, 2025 by John Elliot V 19 Comments

In a recent video our hacker [Electronic Wizard] introduces the 74HC595 shift register and explains how to use it to drive 7-segment displays.

[Electronic Wizard] explains that understanding how to apply the 74HC595 can increase the quality of your projects and also help keep the demands on the number of pins from your microcontroller to manageable levels. If you’re interested in the gory details you can find a PDF datasheet for the 74HC595 such as this one from Texas Instruments.

[Electronic Wizard] explains further that a shift register is like a small one byte memory where its data is directly available on its eight output pins, no input address required. When you pulse the clock pin (CLK) each bit in the eight bit memory shifts right one bit, making room for a new bit on the left. The bits that fall off the right hand side can daisy chain into another 74HC595 going out on pin 9 and coming in on pin 14.

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From Smartphone To A Home Server

August 16, 2025 by Tyler August 27 Comments

Some people like their homelabs to be as big and fancy as possible, with racks of new or surplus server hardware sucking down power. [Hardware Haven] evidently has the opposite idea, given he just made a video about making the cheapest, smallest server possible: an Android phone.

Sure, it’s not going to be streaming terabytes of data at multiple gigabytes per second, but that’s not everyone’s use case. Don’t forget, flagship phones had multiple cores and gigabytes of RAM a decade ago, so even an old and busted smartphone has more than enough power for something like Home Assistant, which is what gets installed in this video.

After considering loading termux and rooting his device for Docker-on-Android, he opted for postmarket OS, the premiere Linux for old smartphones. That’s not because the Linux environment you get with termux wouldn’t work; it’s just that he wanted something native. To that end, he bought a somewhat worse-for-wear Xiaomi Mi A1 from eBay to get hardware Alpine-based postmarket could use.

Software wise, it was just a matter of following instructions and reading manuals — Linux is Linux, after all. The firewall proved to be his main challenge, though trying to branch out from Home Assistant to run Minecraft Server did run into Java issues [Hardware Haven] had no interest in troubleshooting. Hardware wise, though, well — do you want to leave a phone plugged in permanently? Smokey the Bear suggests you not, especially if you live near a forest. Besides, you probably don’t want your server on WiFi, and at least this smartphone wouldn’t charge when using a networking dongle.

That meant phone surgery: the battery came out, and 5 V from an old USB charger was piped into the battery charge controller via a diode. The diode was used for its voltage drop, to bring the 5 V supply down to a believable battery voltage — a buck converter might have been better, but you use what you have, and the diode drop doesn’t dissipate much power. Power dissipation is still one watt at idle, six during a stress test.

Given how cheap the phone was, and how little power this thing sips, [Hardware Heaven] has an excellent answer to those who say homelabbing is a rich person’s hobby. This project also reminds us that while our phones might not be as hackable as we’d like, they’re still far from totally locked down. You can even run NixOS on (some of) them.

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Everyone’s Invited To The Copyparty

July 30, 2025 by Tyler August 47 Comments

Setting up a file server can be intimidating to the uninitiated. There are many servers to choose from, and then you need to decide how to install it — Docker? Kubernates? Well, what’s all that then? [9001] has come to the rescue with Copyparty, a full-featured file server in a single Python script.

It’s light enough to run on nearly anything, and getting it running could not be easier: run copyparty-sfx.py, and you’ve got a server. There’s even a 32-bit .exe for older Windows machines — Windows 2000 seems to be the oldest version tested.

It’ll connect to anything, both in terms of the variety of protocols supported, and the browsers its web interface loads in. The GitHub documentation says browser support : “Yes”, which is pretty accurate going down the list. Sadly Copyparty’s pages do not work in NCSA Mosaic, but IE4 is A-OK.

There’s, FTP, TFTP, HTTP/HTTPS, WebDAV, SMB/CIFS, with unp/zeroconf/mdns/ssdp, etc etc. You need to check the readme for all features, some of which — like transcoding — are only available when dependencies such as ffmpeg installed on the server. Alternatively you can watch the video embedded below to get walked through the features. If the video whets your appetite, can also visit a read-only Copyparty server being demoed on a NUC sitting in [9001]’s basement.

Over the years we’ve seen plenty of folks create personal servers, but the focus is generally on the hardware side of things. While those with more software experience might prefer to configure the various services involved manually, we can definitely see the appeal of a project like Copyparty. In some ways it’s the inverse of the UNIX Philosophy: instead of doing one thing perfectly, this program is doing everything [9001] could think of, and doing it “good enough”.

Thanks to [pedropolis] for inviting us to the Copyparty via the tips line. Building a NAS? Writing software? Hardware?Whatever you do, the tips line is for you.

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