Week 6: Office Hours Notes

Week 6: Questions for Tom’s office hours

  1. MQTT won't work through Cloudflare's proxy. So now my VPS’s IP is exposed. Should I care?
    1. Set up a firewall for any port I’m not using.
    2. Connecting MQTT request via Web Sockets.
    3. Set up MQTT connections as MQTT secure.
      • Set up an SSH key for MQTT;
      • make sure that all my clients
      • Wifi SSL client is old wifi, everything else is the same.
      • On the client side, you can use everything.
        • Secure certificate.
      • DNS is a system of rumours.
      • Every local domain server has to get new records. It would be a lot of traffic.
      • DNS records sometimes are available through one and not other.
  2. ESP32-Wifi-Depth project - changing router to wpa2 multimodal. Any security vulnerabilities?
    1. If yes, are there any microcontrollers that could do WPA3 and CSI?

WIFI issues

  • Desktop Client MQTT Client to see if I can connect to broker
    • Look at Microcontroller client
  1. (Thesis) Wifi network signal strength is directional. Any ways around this?
  2. Platforms for wireframing hardware? Workflows within a VPS.
  3. Could I SSH into my devices? What OS would they need to run? Base requirements? Linux
    2. It would be so fun to try jailbreaking into my old iPhone

2 radios separated by 1.5m. Someone at ITP tried it and didn’t work so well.

Antenna close

I don’t have antenna in my set up.

Design devices in such a way that they get connected/triggered near each other.

Can I design a PCB and choose direction?

WiFi shouldn’t

Tom’s solutions:

Use NFC; NFC NFC

NFC can ask the device which protocol it needs.

Exist Gappleted; AirPlay.

What does

Network Topology (for Dummies?™️)

VPS would be on the same network from the same provider.

MQTT ran on a VPS.

Dis

VPS + Tunnel + Device (Raspberry Pi) ———- (Cloudflare or nGrok).

Write a separate client Node.js script;

Gave a different Cortex;

They go through same MQTT

TODO

  • My ESP32 needs the WiFi antenna.
  • Need to source an NFC connection. Does PI have it?
  • Add firewall to block unused ports.

Office Hours with Fabri - Week 6 - March 4th, 2026

Advice → Save time in measuring and being precise in hyper optimal organizing components inside enclosures; and learn how to make PCBs. A new argument for how I’ve been wasting TIME™️ and ENERGY™️ at ITP. Get tiny terminal blocks if needed.

Wires

Crimping tools remove need for twisting Stringy Wire, but they’re a lot of work.

Solid core wire eventually breaks when bent.

Shop has 22AW gauge.

Soldering

Warm the pad and wire first so that it transfers.

Coat stringy wire with solder using a larger pen.

Flux lowers temp at which solder melts → releases fumes.

ITP solder has flux in it already.

TBD: how/why I burned my personal soddering pen tip.