In some countries Mikrotik is really popular and some cheap ISP management/RADIUS send Mikrotik rate limit only but without editing the pppoe.config the rate limit wont work.
Using the command:
set service pppoe-server authentication radius-settings rate-limit attribute Mikrotik-Rate-Limit wont work all the time with some RADIUS servers.
set service pppoe-server authentication radius-settings rate-limit vendor 'XXXXX’ would do the job.
I tested it adding the vendor to the pppoe.config and worked.
This is an export of my [shaper] section:
[shaper] verbose=1 vendor=Mikrotik attr=Mikrotik-Rate-Limit
Edit1: The Mikrotik Dictionary is installed.