What the metrics mean
- ASR (Answer-Seizure Ratio): the share of answered calls. 40–60% is normal for mobile destinations, call centres see less.
- ACD (Average Call Duration): the average length of answered calls. A sudden drop on a trunk points to bad audio or dropped calls.
- NER (Network Effectiveness Ratio): the share of calls that reached the person, answered, busy or not picked up. The rest is the network's fault. A good NER is above 95%.
Which files work
Asterisk and FreeSWITCH Master.csv files are recognised automatically. Billing, FreePBX, 3CX, Grandstream or carrier exports need a destination column; the rest (time, talk time, status or cause, trunk) are matched by header names and can be fixed by hand. The delimiter (comma, semicolon, tab) is detected.
How to spot a hacked PBX
The usual picture: at night or at weekends one extension or trunk dials expensive destinations (satellite networks, Cuba, Somalia, Pacific islands) with long back-to-back calls. If you see this, change SIP passwords, block international routes by default, add fail2ban and a cap on concurrent international calls.
Related: Erlang calculator, dialplan tester, Telegram monitoring.