With Access Control Lists (ACL) on the BRS, traffic can be filtered through the device, but not access to the device itself.
This is due to the design of the device and is different to other HiOS devices e.g. GRS.
To limit the management traffic on BRS, use the 'IP access restrictions' feature.

CLI:
!*(BRS)#network management access add 1 ip 172.16.17.143 mask 32
!*(BRS)#network management access operation