@nca78 I don't use ATAES132A. I put it in just in case I wanted to invest some more time using it.
I now just use SimpleEncryption, it's secure enough for my purpose atm.
(since the area I live in uses KAKU a lot, an insecure 433MHz lightswitch, I don't think anyone would be bothered to hack my temperature sensors. I found 163 433Mhz devices when I left domoticz logging for a couple of days.)
this kind of optic fiber is probably only plastic so for a full DIY , you can use also fishing wire with a big power led or an old chistmass tree optic fiber lighted.....