In theory, yes. However, it depends on whether the controllers for things like the house’s heating and lights offer this function. From a purely technical point of view, you can set things up so that access to the control unit is restricted to, say, devices that are connected to your local network – e.g. computers that are connected to it via network cables, or devices that are linked up to it via your wireless router. That would make it impossible to control the house via the internet. The exception would be if you had a virtual private network (VPN) that allowed a smartphone, tablet or laptop to log into your home network. You could then switch the heating on while you were on the bus. Alongside using good passwords and certificates and ensuring your software is always up to date, securing your smart-home control system like this is certainly a good idea – although it does involve quite a lot of extra work.
Henning Krause from the division Communications and Media Relations from the Helmholtz Association answered this question.