The purpose of the Redirecting number information element is to identify the number from which a call diversion or transfer was invoked.
The Redirecting number information element is coded as shown in Figure 4-43 and Table 4-32.
The maximum length of this information element is network dependent.
Bits |
||||||||
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
Octets |
Redirecting number Information element identifier |
1 |
|||||||
0 |
1 |
1 |
1 |
0 |
1 |
0 |
0 |
|
Length of redirecting number contents |
2 |
|||||||
0/1 ext. |
Type of number |
Numbering plan identification |
3 |
|||||
0/1 ext. |
Presentation indicator |
0 |
0 |
0 |
Screening indicator |
3a* |
||
Spare |
||||||||
1 ext. |
0 |
0 |
0 |
Reason for redirection |
3b* |
|||
Spare |
||||||||
0 |
Number digits (IA5 characters) |
4 |
||||||
Redirecting number information element
Redirecting number information element
Type of number (octet 3) (Note 1) |
|
Bits |
|
7 6 5 |
|
0 0 0 |
Unknown (Note 2) |
0 0 1 |
International number (Note 3) |
0 1 0 |
National number (Note 3) |
0 1 1 |
Network specific number (Note 4) |
1 0 0 |
Subscriber number (Note 3) |
1 1 0 |
Abbreviated number |
1 1 1 |
Reserved for extension |
All other values are reserved. |
|
Note 1 - For the definition of international, national and subscriber number, see Recommendation I.330 [18]. Note 2 - The type of number "unknown" is used when the user or the network has no knowledge of the type of number, e.g. international number, national number, etc. In this case the number of digits field is organized according to the network dialling plan; e.g. prefix or escape digits might be present. Note 3 - Prefix or escape digits shall not be included. Note 4 - The type of number "network specific number" is used to indicate administration/service number specific to the serving network, e.g. used to access an operator. |
|
Numbering plan identification (octet 3) |
|
Numbering plan (applies for type of number = 000, 001, 010 and 100) |
|
Bits |
|
4 3 2 1 |
|
0 0 0 0 |
Unknown (Note 5) |
0 0 0 1 |
ISDN/telephony numbering plan (Recommendation E.164 [19]) |
0 0 1 1 |
Data numbering plan (Recommendation X.121 [21]) |
0 1 0 0 |
Telex numbering plan (Recommendation F.69 [22]) |
1 0 0 0 |
National standard numbering plan |
1 0 0 1 |
Private numbering plan |
1 1 1 1 |
Reserved for extension |
All other values are reserved. |
|
Note 5 - The numbering plan "unknown" is used when the user on network has no knowledge of the numbering plan. In this case the number digits field is organized according to the network dialling plan; e.g. prefix or escape digits might be present. |
|
Presentation indicator (octet 3a) |
|
Bits |
|
7 6 |
Meaning |
0 0 |
Presentation allowed |
0 1 |
Presentation restricted |
1 0 |
Number not available due to interworking |
1 1 |
Reserved |
Note 6 - The meaning and use of this field is defined in 3/Q.951 and 4/Q.951 |
|
Screening indicator (octet 3a) |
|
Bits |
|
2 1 |
|
0 0 |
User-provided, not screened |
0 1 |
User-provided, verified and passed |
1 0 |
User-provided, verified and failed |
1 1 |
Network provided |
Note 7 - If octet 3a is omitted, "00 - user-provided, not screened" is assumed. |
|
Reason for redirection (octet 3b) |
|
Bits |
|
4 3 2 1 |
|
0 0 0 0 |
Unknown |
0 0 0 1 |
Call forwarding busy or called DTE busy |
0 0 1 0 |
Call forwarding no reply |
0 1 0 0 |
Call deflection |
1 0 0 1 |
Called DTE out of order |
1 0 1 0 |
Call forwarding by the called DTE |
1 1 1 1 |
Call forwarding unconditional or systematic call redirection |
All other values are reserved. |
|
Number digits (octets 4, etc.) |
|
This field is coded with IA5 characters, according to the formats specified in the appropriate numbering/dialling plan. |
|