this week is all about math

It got windy in Aspen which knocked out our power.

What happens to a 'smart' home when the power goes out.

You get visits from the police, fire department (x2) and gas company.  And if I wasn't here to let the gas co in they would have shut off the gas until I could schedule a time to let them into the home to check for a gas leak before restarting the gas.

Where is the math?

Who remembers combinations and permutations?  For those of you who don't there are some not very complicated formulas you can look up, but basically when trying to troubleshoot a system order does matter so you need to look at permutations.  When repetition is allowed the formula is n^r or number of different ways you can do something to the exponent of the number of different ways it can be used.  Wait that is weird and complicated. 

in this house example n= working or not working and r= number of features

a simple (ish) example is troubleshooting a not working light (not smart house)
n=2 (working or not working)
r= 6   (electricity on to house, breaker, bulb, switch working, wiring to socket, socket)


the number of permutations you have to trouble shoot is 2^6 or 2x2x2x2x2x2=64

now in a smart house lets add to r = house wifi working, house router working, lighting wifi working

the number of permutations is now 2^9 or 512 or more than 8Xs more possible points of failure.

I think you probably have started to get my point but to hammer it home with the alarm system in my smart rental house

It has a lot of features---it works on electricity but it has a battery backup, it calls both the alarm company in case of emergency and the relevant service company (fire, police etc) either by landline if available or wirelessly if not, it has sensors to detect a break in, carbon monoxide, gas leak. water leak, AC failure, heat failure, I am sure there are more features but I am going to stop there

possible number of permutations = 2^12 or 4096. 


Bottom line---be mindful of what additional features you add because each ones becomes another possible point of failure and each ones double the number of things you have to troubleshoot. 

KISS=keep it simple stupid (that is directed both at home owners and architects and builders)---fancy feature creep is an expensive hassle --be mindful