AudioCodes Mediant 8000 Installation, Operation & Maintenance Manual page 667

Installation & Operation Manual
NPI
Private [9]
Level 0 Regional (local) [4] A private local extension number. For example:
For NI-2 and DMS-100 ISDN variants the valid combinations of TON and NPI for
calling and called numbers are (Plan/Type):

0/0 - Unknown/Unknown

1/1 - International number in ISDN/Telephony numbering plan

½ - National number in ISDN/Telephony numbering plan

¼ - Subscriber (local) number in ISDN/Telephony numbering plan

9/4 - Subscriber (local) number in Private numbering plan
Version 6.6
TON
Subscriber [4]
Unknown [0]
Level 2 Regional [1]
Level 1 Regional [2]
PISN Specific [3]
41. PSTN Gateway and IP-to-IP Applications
Description
A public number in complete E.164 format
representing a local subscriber. For example:
5551234
A private number, but with no further information
about the numbering plan
A private number with a location. For example:
3932200
2200
667 October 2014