Fishing with WireShark

The software for the Hullpixelbot is coming along nicely. I'm using the amazing esp8266 chip to provide a WiFi connection to the robot and network them all together. Snag is each robot (and whatever we use to tell them what to do) needs to know the network address of all the other robots. 

There's a technology known as mDNS that is supposed to make this easy. It's a local area network version of the Domain Name System that ties the internet together. It uses cunning broadcasts so that systems can find themselves and exchange messages. It's also the basis of the Apple Bonjour zero configuration networking, and there's now an api you can use with Windows 10 Universal Applications to allow them to find and use devices on the local network. 

I couldn't make it work. I tried for a few days and then I used an old software development trick. I asked someone for help. That someone was number one son, who actually took the trouble to read the DNS documentation and tell me what I was doing wrong. And we fixed it.

During our investigations we used an awesome tool called Wireshark. This can capture all the packets on a network, and then provides a set of fantastic tools that let you decode the messages. I think it's great fun to play with, even if you don't have a problem to solve. There's something fascinating about seeing all the messages bouncing around the cable. 

The good news is that we'll be able to appear with a bunch of Hullpixelbots, turn them on and have them all find each other and be found by other machines. I'll publish the software when it's in a state fit for the outside world.