Martin's corner on the web

1.5K followers? – woohoo!

Reminder to self: Arduino's millis() overflows every approx. 50 days, use if ((unsigned long)(millis() – previousMillis) >= interval) instead

I'll be speaking at the "IoT Bulgaria Summit 2019" community event this September, session topic "Securing MQTT for embedded IoT devices with Mutual TLS Authentication". Use this opportunity to chat with me on anything IoT. https://www.eventbrite.com/e/iot-bulgaria-summit-2019-tickets-54290900545?utm-medium=discovery&utm-campaign=social&utm-content=attendeeshare&aff=estw&utm-source=tw&utm-term=listing @Eventbrite

This is why I don't own voice assistants: human workers are listening to recordings from Google Assistant, too: https://www.theverge.com/2019/7/11/20690020/google-assistant-home-human-contractors-listening-recordings-vrt-nws#comments

This is why I chose my IoT development framework carefully. Of course, no one is immune to framework obsolescence: https://www.reddit.com/r/esp32/comments/c9tp0d/super_bummed_spent_almost_2_years_on_a_hobby/

Updated my OTA server to require client certificate to be presented before providing the firmware binary. This way the binary is kept away from curious eyes, and only provided after mutual TLS authentication proves the asking party is who they say they are. #IoT #OTA #Security

Wondering why people fork git projects with the clear intention not to contribute, rather than just starring them?

I am curious if you folks have a separate network for your IoT devices at home? Bonus read on the subject: https://robpickering.com/ubiquiti-configure-micro-segmentation-for-iot-devices/ The poll results are interesting. Looks like 80% of my tech-savvy followers do not have a separate network for their IoT devices, which means either they DIY all of their IoT hardware and…

I am frequently contacted by folks who were advised to use Arduino to build commercial product and are now running into the full spectrum of issues related to using a rapid prototyping platform in production. Someone's giving them the wrong advice and that costs a lot. Also using Arduino code means all of your object…

TIL of the 128 KB limit for MQTT payload size for AWS IoT. Any publish request that contains payload larger than this limit will be rejected and result in a disconnect. Kind of odd, makes it difficult to transport large payloads e.g. frames from cameras or OTA files over AWS IoT.

Working on MQTT rate limiter middleware, it will add an extra layer of security to my already oversecured broker.

Implemented ESP32 OTA rollbacks if the new firmware crashes within 45 seconds of first boot, doesnt manage to connect to MQTT or the device enters degraded operating mode due to failed hardware initialization. This gives me a peace of mind when pushing mass OTA updates. #IoT

Made a short video on my Continuous Delivery setup for ESP32 IoT projects using Node-RED https://youtu.be/paC_rVziIMQ #IoT #MQTT #OTA #ESP32

Just recorded a new video: Provisioning ESP32 devices for mutual TLS authentication for MQTT using own PKI https://youtu.be/7qTT9EPCdCw #IoT #mTLS #MQTT #security #PKI #DIY #eclipse

Made a "how-to" video on how to use self-created CA to secure Node-RED installation with mutual TLS authentication in 12 minutes: https://www.youtube.com/watch?v=oRCpXEj236s&feature=youtu.be #IoT #nodered #tls #mtls #security

I need a node.js guru volunteer to work with me on creating basic PKI PoC that provisions #ESP32 devices with client certificates; node-forge looks right for the purpose. I have the complete solution architecture figured, just need a node.js guru that can code it for free 🙂 Couple volunteers already, thanks @eliofilipe and @MrQinEL ;…

I now load x.509 certificates to dedicated ESP32 partitions rather embedding into the code via COMPONENT_EMBED_TXTFILES; This helps decouple the code from provisioning the device with CA and client certificate+key; Still working on PKI to provision the certificates at flash time

Saw someone drop his wallet while entering a shop (pretty full with cash btw) and ran up to him to return it. Feels good to help, I have been in a position where I've lost wallet with IDs, credit cards and know what it means..