I wanted to follow the idea of provisioning.
Therefore I need a rule.
I thought, I’d make that with a regex for Mac-address-based …
I searched and found: http://forum.mikrotik.com/t/create-a-new-ap-access-rule-with-regular-expressions/168192/1
But instead of finding an answer how to regex, I find a guide how to not use regex and instead play with firewall rules…