The correct companding law is dependent upon the physical interface type and switch variant. | Port Type | Protocol/Switch Variant | Companding Law |
|---|
| T1 | ISDN/CAS | Mu-Law | | E1 | ISDN/CAS | A-Law | | BRI | Japan ISDN | Mu-Law | | BRI | ETSI/QSIG | A-Law |
CautionMisconfigured Companding Laws may result in dropped calls and/or poor audio quality. Symptoms include dropped outgoing ISDN/BRI calls and loud crackling noises on ISDN/Analog and BRI/Analog calls. |