Until last year, work had Mitel 5212 softphones as the main devices on desks. This was the case since 2008, and was apparently high time to replace them. As they had nowhere to go but the bin, I grabbed a few in the hope to use them at home. While Mitel has a proprietary protocol (MiNET), they also support standard SIP through another vendor firmware, which allowed me to add a few more physical phones behind my FRITZ!Box.
Today, when trying to log in remotely to my home router (a FRITZ!Box), I was greeted with an TLS certificate error. I was pretty sure it’s my router, but am I really keen to type in a password into a field that I have no idea whether it is actual my machine, or a nice-looking replica? A clear indication that it is time to use a better cert than a self-signed one that I cannot verify remotely.
I use Let’s Encrypt for all my other certificates, so why not use it on my router? However, I found precious little information about how to use it with the FRITZ!Box. Fortunately, it’s pretty straightforward.