Dynamic Speed change of user from Freeradius

Hi All,

I am using hotspot feature on my mikrotik with freeradius. I want to dynamically reduce speed of user.

Example:

A) Total bandwidth available it 10 Mbps

User demo@x logins with his first device and he is assigned 2 Mbps from radius server, if user demo@x logins again with his second device, the speed needs to be equally divided like 1 Mbps for each device.

Radius server can check if first user is online and do COA for first login and second login, but how can we communicate this to Mikrotik using vendor specific attribute ?

Regards,
Dipin Thomas
email:dipinthomas2003@gmail.com