3Com MSR 50 Series Configuration Manual page 427

Table 9 Types and code schemes of ISDN numbers
Field (Bit) value
Type
Protocol 8 7 6 5
DSS1 0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 1 0
1 1 1
ETSI 0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 1 0
1 1 1
NI 0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 1 0
Code scheme
4 3 2 1 Definition
Unknown
International number
National number
Network specific number
Subscriber number
Abbreviated number
Reserved for extension
0 0 0 0 Unknown
0 0 0 1 ISDN/telephony numbering plan
(Recommendation E.164)
0 0 1 1 Data numbering plan (Recommendation X.121)
0 1 0 0 Telex numbering plan (Recommendation F.69)
1 0 0 0 National standard numbering plan
1 0 0 1 Private numbering plan
1 1 1 1 Reserved for extension
Unknown
International number
National number
Network specific number
Subscriber number
Abbreviated number
Reserved for extension
0 0 0 0 Unknown
0 0 0 1 ISDN/telephony numbering plan
(Recommendation E.164)
0 0 1 1 Data numbering plan (Recommendation X.121)
0 1 0 0 Telex numbering plan (Recommendation F.69)
1 0 0 0 National standard numbering plan
1 0 0 1 Private numbering plan
1 1 1 1 Reserved for extension
0 0 0 0 Unknown number in Unknown numbering plan
0 0 0 1 International number in ISDN numbering plan
(Rec. E.164)
0 0 0 1 National number in ISDN numbering plan (Rec.
E.164)
1 0 0 1 Network specific number in private numbering
plan
0 0 0 1 Local (directory) number in ISDN numbering plan
(Rec. E.164)
1 0 0 1 Abbreviated number in private numbering plan
Configuring ISDN 427