Chat server on a WiFi-enabled SD card | Hacker News Reader

Chat server on a WiFi-enabled SD card

l-o-o-s-e-d.net

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It appears that the linked web page may also be running on a WiFi-enabled SD card and can't handle the load.

I'm sorry, I need to figure out how to handle traffic better/dynamically.. Still learning. I was thinking it would be cool to leave websites "in the wild" though, like something solar powered that would stay alive and could be accessed in the area. Or something with a short lifespan that's battery powered...

We actually did something like this at uni. Meshnet using low-power radio receivers with arduino uno and whatever else you want (gps?), a few power-stations that had solar powerbanks and 3G connection. Power stations were collecting data from the mestnet and sending it to a server. Weak nodes only required battery to be changed less often than every 3.5 month. I thought it was pretty cool.

I'm wondering how doable it would be to make such a mesh network but using LoRaWAN instead, and ensuring privacy using E2EE.

That'd be a nice project to work on.

I think the reason most WISP's are done with industry-grade receivers/transmitters (like Unifi) is the bandwidth/speed limitations of LoRa. I think, for the most part, LoRa is used mainly for remote monitoring and other low-bandwidth applications. Somebody correct me if I'm wrong.

We did it back in ~2011/2012, LoRa wasn't a thing back then.

Post a link if you have one! I'd love to check it out.

I sadly don't have any documentation left from this project.

Our goal was to build lowest possible energy consumption GPS tracker with "live" feedback, 2h delay was acceptable not ideal, 30min was just ideal. It was close to 30min on good weather.

I remember it used Ardunio Uno with xbee or zigbee with mesh module on radio, whichever had lower power consumption. GPS module was checking for fix every 30minutes, transmitting the location to master nodes which were sending it to our server.

Master nodes were located on hills without trees with solar-powerbanks, so even if there was no sun it would keep the nodes running for 2 months, GPS nodes were in areas without even GSM signal, and even on hills 3G was not guaranteed.

GPS nodes had replaceable rechargeable batteries, had to be changed every 3.5months. We didn't care about speed transmission.

We had budget of max. £15000 (including hardware, software and any legal fees and SIM card maintenance) for around 350 devices.

That sounds really neat. If you manage to dig any photos or documentation send it over!

It could be cool for creating some equivalent of wifi geocaching. Small simple websites that you need to get within a specific area to access.

...and somehow pay for its rx/tx costs

For small range (few km) you can just utilise LoraWAN for free communication.

This is a technology that is very interesting to me, but I have not gotten my hands on it yet. I know there were some Italians who had gotten some 100s of km using LoRa (I think it was testing for the Guifi network)

> could be accessed in the area

If you didn't want remote access you would not have to pay rx/tx costs.

They just didn't use the right SD card. You need a class 11 Super ULTRA Extreme SD card made by some specific brand.

We're all being funny, but I definitely have my eye on using underpowered servers along with a more JAMStack-flavored design so that some projects I'm working on stay available even when the load essentially kills all updates.

All the way back in Slashdot Effect days I recall a couple of people getting clever with Referer (sic) headers to detect someone on a tech news site linking to your website. In those cases they would redirect to a public cache, like Google's, reducing origin server traffic to a few packets per request.

I always found that to be way more clever than people gave it credit for.

Only if you are a filthy causal, specific brand vertically integrated sd cards are so 2019.

So what you need to do, if you are serious about this micro server business, is buy a 1.5TB optane 905p and slot it into a pcie x4 to m.2 adapter. From there you will need a M.2 nvme to usb converter(make sure you don't get a SATA-only one). I like to strip out the inside of a tuff nano, but any will do. Now that you have your drive basics setup, you will need a type c to type a usb cable so that you can plug this into a Pi4. You could use the usb c port on the Pi4, but then how will you power the pi4, dummie? From there you will have to write a small driver that translates sd protocol commands to usb mass storage commands. Now get some wires and solder the Pi4's GPIO pins (the ones you used as I/O for your driver) to the micro sd pins on the adapter. And that's it, now you have a real SD card that is actually fast enough to run your server from an SDIO adapter! Wasn't that easy? Plus this way you didn't have to give $am$ung or $andisk any of your money.

No, unfortunately the high-throughput firmware is reserved for the class 11 Super ULTRA Extreme PRO SD card

Damn, the salesman did say I was taking an awful risk not getting the MonsterCable(tm) Super Extra ULTRA Extra Extreme SD+ card but I wasn't prepared for the extra $129.99 it cost over my SanDisk.

Oh, it does. You just can't handle the wait :)

The site is down but I'm assuming that this is making use of one of those old SD-cards that had wifi built in to turn old old point and shoot cameras into wifi devices.

I remember someone got linux running on one of them and ever since then I wish that that form-factor for small computing had taken off.

Imagine if the raspberry pi people made devices like this.

Look into VoCore2, it’s a modern-ish Linux SBC in a very small form factor: https://vocore.io/v2u.html.

This is very cool though a touch pricey. Do you have any hands on experience with them? How's the quality?

It's goodish, the firmware is hard to get right and the chip itself gets waaaarm

"... and ever since then I wish that that form-factor for small computing had taken off."

I know how you feel, but the form factor I prefer is PCMCIA[1].

Interestingly, someone did, in fact, attempt to create a small, modular, computing standard based on PCMCIA - the card was a compute module that could be inserted into a shell laptop ... I cannot find the link, unfortunately ...

[1] "People Can't Memorize Computer Industry Acronyms"

Totally man, the path I had envisioned SBCs going was PCMCIA form factor and SD form factor. Imagine a PCMCIA computer with an SD slot to put your SD form factor computer into.

https://www.youtube.com/watch?v=dE5ROl2YPbs

I found it - it is "EOMA68":

https://www.crowdsupply.com/eoma68/micro-desktop

There are lots of SD card sized devices out there. A bit thicker because of packaging, but, still pretty small.

On a slightly different take, Octavo makes Pi Zero like devices (single core, 512MB) but with Ethernet and (IIRC) eMMC memory within a single package itself smaller than an SD card. I would love to design a board with a couple of them and a network switch.

Anyone remember the Palm Wifi SDIO card? I always wanted one for my Zire 72...

I cannot visit the site either so I ask it here. How does a wifi card work? Mounting of the file system is a host concept. How can a SD card let the host know its contents have been updated?

SD cards are implemented with a bus interface that's quite general. The only thing they provide to the host is block-addressed memory. The file system is an OS abstraction on top of that.

So, the host computer would simply address the WiFi chip on the bus, and issue commands and transfers, similar in overall design to how it would talk to a PCIe device or USB device.

So the host device does need support for a wifi SD card? I thought it was an perfect abstraction.

Since this site is dead right now. Here's something similar to read about in the meantime.

https://hackaday.com/2016/06/30/transcend-wifi-sd-card-is-a-...

Sorry mane.

I'm mostly of the opinion now that we should just treat our computers as a network of connected computers all doing special jobs.

For instance, why not treat a hardware RAID controller as on-board NAS, or even run PostgreSQL (or even just SQLite) directly on the card?

You buffer a bottleneck by controlling the ingress, the egress, or both (eg, a caching proxy server with gzip compression), but these days we don't see 'or both' as often as maybe we used to.

You can treat your NAS as a hardware RAID controller. You will get similar performance as you would get from treating your hardware RAID controller as an on-board NAS.

This is how you start ftp-server in the SD-card. I have never found any other useful application you could start yourself:

    SDCARD/$ cat autorun.sh 
    telnetd -l /bin/bash &
    tcpsvd -vE 0.0.0.0 21 ftpd &

Oh. There is telnet too. Funny but not useful.

archived google cache: https://archive.vn/pYoTM

Hey, that's cool! thanks!

Needs moaarr links for sinking time, like so:

[0] https://hackaday.com/2016/06/30/transcend-wifi-sd-card-is-a-...

Modifying Transcend WiFi SD Card Firmware (fernjager.net) Apr 25, 2014

[1] https://news.ycombinator.com/item?id=7647434

[2] https://web.archive.org/web/20160509130411/http://www.fernja...

[3] https://jamesone111.wordpress.com/2014/03/19/exploring-the-t...

Transcend WifiSD / PQI AirCard / FluCard Pro, 16 Aug 2013

[4] https://forum.archive.openwrt.org/viewtopic.php?id=45820&p=1

[5] http://haxit.blogspot.com/2013/08/hacking-transcend-wifi-sd-...

[6] https://elinux.org/Wifi_SD

Now the only question reamains if this applies to any currently available product at all, or if things changed so much that it doesn't work anymore.

Site is down. The words 'WiFi-enabled SD card' makes my imagination flow. I think in the future you'll have one SD card with all the electronics/computing power and you just insert it into various dummy devices to change it's capabilities.

The original NeXT vision was optical drives. You'd keep your $HOME directory on one and plug in to whatever machine you were in front of.

I remember when the iPhone came out, I wondered if the idea would be updated, but no.

Of course the world went more in the direction of Sun's network computer/JavaStation idea, where other people's computers substitute for the optical/SD card.

There was a "Home on iPod" feature available in at least a beta version of OS X [1]. I remember testing it at one point.

[1] https://appleinsider.com/articles/03/12/01/apple_tweaking_ho...

i remember that feature and dreaming of how awesome it would be... sigh.

As Lammy said, it's not new. There was Eye-Fi, which was an SD card for cameras, but with a WiFi module so you can grab pictures off it from your computer. And there was SDIO, which was a WiFi module for your non-WiFi Palm Pilot, which you'd plug into your SD card slot: https://www.youtube.com/watch?v=vCqn_WpFSH4

And, you can even reprogram the microcontroller inside seemingly normal (micro-)SD cards: https://www.bunniestudios.com/blog/?p=3554

Search ‘SDIO’ as a starting point :)

That is a sick idea. Just saw another post today about a pure JS os. Really interesting thought.

I remember when these cards were new, every month or so you'd see a story about someone recovering their fancy digital camera because the doofus who stole it didn't realize the SD card was phoning home.

wish I still had all of those old Eye-Fi cards

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