I received a Netduino Plus for Christmas this year to keep my other Netduino company. After working my way through the "Internet of things" book from O'Reilly, I decided to write a Netduino MQTT client after hearing about MQTT a few weeks earlier.
MQTT is a light-weight protocol for machine to machine communications, or "Internet of things" communications. This seemed like a fun project with my goal being to monitor the temperature, of my desk... Which I sit at... But enough of that! - It's a Netduino with Ethernet! That is cool enough that it doesn't have to be useful yet.
I haven't got the temperature bit working (I bought a 1 wire sensor before I learned of the issues that choice brought with it - I'm waiting for an analog solution now ), but I have written an MQTT publisher/client that I thought I'd share with you. I've already learned so much from this forum (motor drivers, USB HID, shift registers, etc) that I hope that this might be useful to some of you in your future projects.
I have a page on my blog: http://diabolicalws....tduinomqtt.html
I have this hosted on Github here: https://github.com/d...an/NetduinoMQTT
MQTT operates in a publisher/subscriber model where you either post messages to a named topic or you can subscribe to a named topic. If you publish to that topic, all clients on that broker, who are subscribed to that topic - will get your message. At this point, I have only implemented the publish parts and the most basic QoS level.
If you download the code from GitHub, just add it to a Netduino Plus project, change the Program.cs as needed (IP address, login/passwd, etc), and deploy it, you can send MQTT messages to an MQTT broker (on button press for now).
This project was very fun - I found myself up at 4 in the morning on several occasions - awaiting "one more change". That hasn't happened for me in awhile, so it was quite fun.