Ok, I got carried away.
Uncategorized
7
Posts
3
Posters
17
Views
-
Ok, I got carried away. 😆
I added two more nodes:
- it01.bsd.cafe in Italy
- nl01.bsd.cafe at @OpenBSDAmsBoth are based on OpenBSD.
-
Ok, I got carried away. 😆
I added two more nodes:
- it01.bsd.cafe in Italy
- nl01.bsd.cafe at @OpenBSDAmsBoth are based on OpenBSD.
@stefano @OpenBSDAms nodes which do what?
-
@stefano @OpenBSDAms nodes which do what?
@km @OpenBSDAms at the moment, they're caching and sending out the media files. Media is the most critical part of the Mastodon experience as websockets help to keep latency low (even if it's not that low), but media loading can overload the media server and make the experience slower. Replicating them around the world helps.
I've described this kind of setup here: https://it-notes.dragas.net/2024/08/26/building-a-self-hosted-cdn-for-bsd-cafe-media/
-
@km @OpenBSDAms at the moment, they're caching and sending out the media files. Media is the most critical part of the Mastodon experience as websockets help to keep latency low (even if it's not that low), but media loading can overload the media server and make the experience slower. Replicating them around the world helps.
I've described this kind of setup here: https://it-notes.dragas.net/2024/08/26/building-a-self-hosted-cdn-for-bsd-cafe-media/
@stefano @OpenBSDAms i had guessed it'd be something for mastodon, but didn't know what exactly. thank for the details!
-
@stefano @OpenBSDAms i had guessed it'd be something for mastodon, but didn't know what exactly. thank for the details!
@km @OpenBSDAms in the future, I'll also make some of them "entry points" for the other services, too. Caching everything possible.
-
Ok, I got carried away. 😆
I added two more nodes:
- it01.bsd.cafe in Italy
- nl01.bsd.cafe at @OpenBSDAmsBoth are based on OpenBSD.
@stefano @OpenBSDAms Congrats! How do you manage those servers?
-
@stefano @OpenBSDAms Congrats! How do you manage those servers?
@radhitya @OpenBSDAms Thank you. I have a custom script that updates the Varnish vcl
Feed RSS
Gli ultimi otto messaggi ricevuti dalla Federazione
-
What a hole.
Kiev 60
Zodiak-8 30mm F3.5
Lomography Metropolis
-
Even when there’s no accountability, the record matters. Credit to the Wikipedia editors maintaining this page.
-
Tamper Detection with Time-Domain Reflectometry
For certain high-security devices, such as card readers, ATMs, and hardware security modules, normal physical security isn’t enough – they need to wipe out their sensitive data if someone starts drilling through the case. Such devices, therefore, often integrate circuit meshes into their cases and regularly monitor them for changes that could indicate damage. To improve the sensitivity and accuracy of such countermeasures, [Jan Sebastian Götte] and [Björn Scheuermann] recently designed a time-domain reflectometer to monitor meshes (pre-print paper).
Many meshes are made from flexible circuit boards with winding traces built into the case, so cutting or drilling into the case breaks a trace. The problem is that most common ways to detect broken traces, such as by resistance or capacitance measurements, aren’t easy to implement with both high sensitivity and low error rates. Instead, this system uses time-domain reflectometry: it sends a sharp pulse into the mesh, then times the returning echoes to create a mesh fingerprint. When the circuit is damaged, it creates an additional echo, which is detected by classifier software. If enough subsequent measurements find a significant fingerprint change, it triggers a data wipe.
The most novel aspect of this design is its affordability. An STM32G4-series microcontroller manages the timing, pulse generation, and measurement, thanks to its two fast ADCs and a high-resolution timer with sub-200 picosecond resolution. For a pulse-shaping amplifier, [Jan] and [Björn] used the high-speed amplifiers in an HDMI redriver chip, which would normally compensate for cable and connector losses. Despite its inexpensive design, the circuit was sensitive enough to detect when oscilloscope probes contacted the trace, pick up temperature changes, and even discern the tiny variations between different copies of the same mesh.
It’s not absolutely impossible for an attacker to bypass this system, nor was it intended to be, but overcoming it would take a great deal of skill and some custom equipment, such as a non-conductive drill bit. If you’re interested in seeing such a system in the real world, check out this teardown of a payment terminal. One of the same authors also previously wrote a KiCad plugin to generate anti-tamper meshes.
Thanks to [mark999] for the tip!
-
Feditarian Fediversalist
-
@DavidBHimself I guess we will have to agree to disagree on this one.
And yes, I did lose my right to vote when I moved a couple of times, even as a resident+citizen of said location. That’s how our imperfect electoral system works. 😥
-
-
@evan I agree with @EricLawton -- "expatriate" is an imperial term. I see no confusion of terminology in his comment, quite the opposite.
In the context of the poll, "expatriate" was used about emigrants, not immigrants, but the point stands. The clearest term, if a bit long and pedantic, might have been "citizens who are not residents".
-
@DavidBHimself I’m suggesting that you should be able to vote where you live.
