ITU-X25 Packet layer - Facilities
01 - Reverse charging / Fast select
| - Octet : |
facility code |
| bits 8-1 |
01 H |
| - Octet 1: |
facility parameter field |
| bits 8-7 |
Fast select |
| bits 6-2 |
00000 |
| bit 1 |
Reverse charging |
|
|
|
bit 1 |
Reverse charging |
|
0
|
Reverse charging not requested
|
|
1
|
Reverse charging requested
|
|
|
|
|
bits 8-7 |
Fast select |
|
0 0
|
Fast select not requested
|
|
0 1
|
Fast select not requested
|
|
1 0
|
Fast select requested with no restriction on response
|
|
1 1
|
Fast select requested with restriction on response
|
02 -
Throughput class negociation
| - Octet : |
facility code |
| bits 8-1 |
02 H |
| - Octet 1: |
Coding of throughput class |
| bits 8-5 |
From the called DTE |
| bits 4-1 |
From the calling DTE |
|
|
| bits dcba |
Throughput class |
| 0 0 0 0
|
Reserved
|
|
0 0 0 1
|
Reserved
|
|
0 0 1 0
|
Reserved
|
|
0 0 1 1
|
75
|
|
0 1 0 0
|
150
|
|
0 1 0 1
|
300
|
|
0 1 1 0
|
600
|
|
0 1 1 1
|
1200
|
|
1 0 0 0
|
2400
|
|
1 0 0 1
|
4800
|
|
1 0 0 1
|
4800
|
|
1 0 1 0
|
9600
|
|
1 0 1 1
|
19200
|
|
1 1 0 0
|
48000
|
|
1 1 0 1
|
64000
|
|
1 1 1 0
|
Reserved
|
|
1 1 1 1
|
Reserved
|
03 -
Closed user group selection
| - Octet : |
facility code |
| bits 8-1 |
03 H |
| - Octet 1: |
Closed user group selected for the virtual call |
| bits 8-5 |
First digit (binary coded decimal) |
| bits 4-1 |
Second digit (binary coded decimal) |
08 - Called line address modified notification
| - Octet : |
facility code |
| bits 8-1 |
08 H |
| - Octet 1: |
facility parameter field |
| bits 8-1 |
Called line address modified notification |
|
|
| bits 8 7 6 5 4 3 2 1 |
Called line address modified notification |
| 0 0 0 0 0 0 0 1 |
Call redirection due to originally called DTE busy |
| 0 0 0 0 0 1 1 1 |
Call distribution within a hunt group |
| 0 0 0 0 1 0 0 1 |
Call redirection due to originally called DTE out of order |
| 0 0 0 0 1 1 1 1 |
Call redirection due to prior request from originally called DTE for
systematic call redirection |
| 1 1 x x x x x x |
Called DTE originated (a) |
| 1 1 x x x x x x |
Call deflection by the originally DTE address (b) |
| TABLE 32/X.25 (ITU) |
(a): Each X may be independently set to 0 or 1 by the called
DTE and is passed transparently to the calling DTE. Bit 8, when received from
the called DTE, and when it is not set to 1, is forced to 1 by the DCE.
(b): The Xs are those set by the originally called DTE in the call
deflection selection facility.
09 - Closed user group with outgoing access selection
|
- Octet : |
facility code |
|
bits 8-1 |
09 H |
|
- Octet 1: |
Closed user group selected for the virtual call |
|
bits 8-5 |
First digit (binary coded decimal) |
|
bits 4-1 |
Second digit (binary coded decimal) |
41 - Bilateral closed user group selection
|
- Octet : |
facility code |
|
bits 8-1 |
41 H |
|
- Octet 1: |
Bilateral closed user group selected |
|
bits 8-5 |
First digit (binary coded decimal) |
|
bits 4-1 |
Second digit (binary coded decimal) |
|
- Octet 2: |
Bilateral closed user group selected |
|
bits 8-5 |
Third digit (binary coded decimal) |
|
bits 4-1 |
Fourth digit (binary coded decimal) |
42 - Packet size
| - Octet : |
facility code |
| bits 8-1 |
42 H |
| - Octet 1: |
facility parameter field |
| bits 8-5 |
0000 |
| bits 4-1 |
Packet size from the called DTE |
| - Octet 2: |
facility parameter field |
| bits 8-5 |
0000 |
| bits 4-1 |
Packet size from the calling DTE |
The values available for each direction are as follows:
|
bits 4 3 2 1 |
Packet size |
|
0 1 0 0
|
16
|
|
0 1 0 1
|
32
|
|
0 1 1 0
|
64
|
|
0 1 1 1
|
128
|
|
1 0 0 0
|
256
|
|
1 1 0 1
|
512
|
|
1 1 0 0
|
1024
|
|
1 1 1 0
|
2048
|
|
1 1 1 1
|
4096
|
43 - Window size
|
- Octet : |
facility code |
|
bits 8-1 |
43 H |
|
- Octet 1: |
facility parameter field |
|
bit 8 |
0 |
|
bits 7-1 |
Window size from the called DTE |
|
- Octet 2: |
facility parameter field |
|
bits 8 |
0 |
|
bits 7-1 |
Window size from the calling DTE |
The values of window coded on bits 7-1 are binary coded.
44 - RPOA selection
|
- Octet : |
facility code |
|
bits 8-1 |
44 H |
The parameter field contains the data network identification code DNIC corresponding to the initial RPOA transit network requested.
|
- Octet 1: |
Identification code |
|
bits 8-5 |
First digit (binary coded decimal) |
|
bits 4-1 |
Second digit (binary coded decimal) |
|
- Octet 2: |
Identification code |
|
bits 8-5 |
Third digit (binary coded decimal) |
|
bits 4-1 |
Fourth digit (binary coded decimal) |
49 - Transit delay selection and indication
| - Octet : |
facility code |
| bits 8-1 |
49 H |
| - Octets 1-2: |
Transit delay |
| bits 16-1 |
Number in milliseconds from bit 16 to bit 1 (binary coded). Value from 0
to 65534. |
C3 - Call redirection or deflection notification
|
- Octet : |
facility code |
|
bits 8-1 |
C3 H |
|
- Octet 1: |
Length in octets of facility paramater field |
|
bits 8-1 |
= n+2, where n is the number of octets necessary to hold the originally called DTE address. |
|
- Octet 2: |
facility parameter field |
|
bits 8-1 |
Reason for the call redirection or call deflection |
|
- Octet 3: |
facility parameter field |
|
bits 8-1 |
Number of semi-octets in the originally called DTE address |
|
- Octets 4-4+(n-1): |
facility parameter field |
|
|
Originally called DTE address (n octets) |
|
|
|
|
bits 8 7 6 5 4 3 2 1 |
Coding of the reason |
|
0 0 0 0 0 0 0 1 |
Orig. called DTE busy": |
|
0 0 0 0 0 1 1 1 |
Call dist. within a hunt group |
|
0 0 0 0 1 0 0 1 |
Orig. called DTE out of order |
|
0 0 0 0 1 1 1 1 |
Systematic call redirection |
|
1 1 x x x x x x |
Call deflection by the originally DTE address (a) |
|
TABLE 31/X.25 (ITU) |
(a): The Xs are those set by the originally called DTE in the call deflection selection facility.
D1 - Call
deflection selection
| - Octet : |
facility code |
| bits 8-1 |
D1 H |
| - Octet 1: |
Length in octets of facility parameter field |
| bits 8-1 |
= n+2, where n is the number of octets necessary to hold the called
address of the DTE to which the call is to be deflected (the alternative
DTE). |
| - Octet 2: |
facility parameter field |
| bits 8-1 |
Reason for the DTE deflecting the call |
| - Octet 3: |
facility parameter field |
| bits 8-1 |
Number of semi-octets in the alternative DTE address |
| - Octets 4-4+(n-1): |
facility parameter field |
|
Alternative DTE address (n octets) |
|
|
| bits 8 7 6 5 4 3 2 1 |
Reason for the call deflection |
| 1 1 x x x x x x |
Call DTE originated |
| 