Protocol

CAS / R2

Channel Associated Signaling · MFC-R2

Lab ready Full lab

Channel Associated Signaling and MFC-R2 multi-frequency compelled trunk signaling used on legacy TDM interconnects. Line signaling may be robbed-bit or dedicated bits; register signaling exchanges address digits with R2 tones. ISDN PRI and SIP have largely replaced it, but international gateways still see it.

Domains

Tags

casr2trunkmf

Sources

  • ITU-T Q.400–Q.490 (R2)
  • ANSI robbed-bit CAS

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