This read-write floating-point object sets the high-water-mark Background Blocks Error Rate above which the terminal raises a BBER alarm, flagging a rise in errored blocks measured outside of severely errored seconds. An administrator uses this to catch a subtler, ongoing quality issue on the link that wouldn't necessarily trip the more severe SES-related alarms. For example, a creeping BBER trend well before any severely errored seconds occur can give advance warning of an antenna alignment drifting out of tolerance.