EXFO FTB-8500 Series for FTB-500 - Manual (Page 142)

Summary Tabs
128 FTB-8500 Series and FTB-8120NGE/8130NGE
Alarm Summary

Higher Layer Protocol (Ethernet): Indicates the presence of any error
related to the HLP over Ethernet (IP header checksum, UDP
checksum, TCP Checksum (FTB-8510B), and IPTV (FTB-8510B)).

Pattern (BERT): Indicates the presence of any alarms/errors related to
pattern testing such as No Traffic, Pattern Loss, and Bit Error.
Indicates also the Bit Error rate and count.

Other: Indicates all other alarms/errors such as SDT (Available with
Ethernet BERT test only).