System Diagrams and Photos
A special remote hub control capability was developed using the UDP request/reply mechanism where whenever a UDP datagram with the keyword "send_commands" is received, the house server looks up the value of the redis key udp_reply_to_hub and sends it back to the originator of the datagram (presumably the hub...), then resets the key value to a "Got your datagram!". The hub interprets the reply and executes the commands described in the next subsections.
To send a command you have to log onto www.zouck.org, then start a redis-cli session, then set the key to the correct value, then wait until the key value returns to "Got your datagram!" This capability was made unweildy to make it intentionally difficult to do so that it would not be overused, since some commands like ssh or snap can eat up internet data quickly.
To reboot the hub, which should be done infreqently, you need to log on to the VPS (www.zouck.org) with ssh, run the redis-cli, then set the key "udp_reply_to_hub" key value to "reboot31415".
To shutdown, which sould never be done while away since you can't start it again, set the same key to "shutdown31415".
To start a reverse ssh tunnel from the VPS to the Raspi set the same key to "tunnel31415". This will allow you to ssh to the Raspi using "ssh p1@localhost -p 19999" from a logon session on www.zouck.org
To snap a picture from the webcam and send to this server, set the key to "snap31415"