Panasonic KX-TDA30 Features Manual page 204

1.20 Integrated Services Digital Network (ISDN) Service Features
• ISDN extensions can belong to an incoming call distribution group (→ 1.2.2 Incoming Call Distribution
Group Features) or idle extension hunting group (→ 1.2.1 Idle Extension Hunting). In this case, an MSN
can be assigned.
• If the last digit of the MSN is "0", all terminal devices on the same ISDN port receive the call
simultaneously, if the specification of each terminal device is available. To use the MSN whose last digit
is "0" as an individual MSN, system programming is required for each ISDN port.
Feature Guide References
1.1.1.4 Multiple Subscriber Number (MSN) Ringing Service
204 Feature Guide