Finally I got around to trying to draw the first network diagrams for The Asia House. The first one shows the general network wiring, from the incoming DSL and cable TV wiring through to the LAN wiring to each room in the house.

In addition to the DSL and cable TV lines, the house will also connected to the outside world through a wireless GSM modem, which will be used primarily to automatically send SMS messages to the house occupants in case of security incidents. The home control server is connected to the Internet through a firewall. The home control server and the media server, and in the future possibly other servers as well, are connected to the local controllers, to the touch screen controllers and to the PC’s throughout the house through a standard Ethernet LAN. The incoming phone line is connected to a PABX that we happened to have left over from a previous business, and all phones in the house are connected to the PABX such that we can conveniently dial from room to room as well. The incoming cable TV signal will in the future be combined with video generated by the media server, and with video coming from security cameras, and then distributed throughout the house. This will allow for the implementation of some pretty cool functions in the future

All the major rooms have LAN jacks for PC’s or laptops, and a wireless access point in the dining area should provide sufficient coverage outdoors. Likewise, all major rooms either have a phone, or a provision for a phone. With regards to television, we really only plan to have a TV in the guest-room-combined-TV-room for now, but there will be TV jacks in all major rooms. There will be ceiling-mounted speakers in a couple of the rooms, but we probably won’t be streaming audio to them from the media server for the next year or two, as I’ll have some work to do to implement that in a cost-effective manner.

The touch screen controllers are essentially distributed processors (based on Rabbit core modules) to which I connect intelligent LCD touch screens. These touch screens form the primary means whereby the occupants of The Asia House will interface with the home control system. The “local controllers”, as I call them, connect the server via the LAN to several auxiliary devices, which I attempt to explain on the second network diagram.

I am currently planning to utilize three local controllers, each one managing the auxiliary devices on one floor of The Asia House. Each controller handles IR communication with devices in selected rooms, reads sensors and push buttons, controls devices, and communicates (securely) with the home control server. A wireless controller (probably using Zigbee or Z-Wave) may be used in the future to control the lights in the house.

Each room that is equipped with an air conditioning unit or with a TV has an IR transceiver which can be used by the server to send signals to turn on or off the aircon, or to turn off the TV. The same transceiver can also be used to receive signals from a remote control in the room, which allows the room occupant to communicate with the server to, for example, increase the volume on piped-in audio. All bedrooms will (subsequently) be provided with a small occupancy sensor to allow the home control system to, for example, turn off the aircons if the rooms have been empty for some time, or to brighten the bathroom lights a little if the children wake up at night.

There is a water sensor in the kitchen, and another one in the downstairs laundry/kitchen area. There is one smoke sensor on each floor, centrally located near the staircase. There are also “panic buttons” behind the doors of the three main exterior entrances, which the occupants can press if they feel threatened by any visitor at the door. Finally, the home control system is also connected to external flood lights, a siren and a strobe light, which can be activated manually or automatically depending on the situation.

In addition to the local controllers on each floor, there may also be other controllers added in the future. One important controller which I intend to add relatively soon is a data acquisition module to monitor the power consumed by each electric circuit in the house. This will be an analog data acquisition board with one analog input channel per circuit, connected to inductive sensors placed around the wiring near each circuit breaker, similar to how a clamp ammeter is used. With the current consumption monitored over time, we can not only improve the way we use appliances, we can also automatically be issued a warning signal if, for example, a water heater has remained on for an unusual length of time.