General
Implementation
The purpose of this section is to describe different traffic cases and how the information exchange between GSM-R and MX-ONE is handled in these cases. The configuration and functions used in GSM-R are not described in the chapter.
Existing Function for Priority
As functions similar to the requirements for priority already exist within Control Telephony Function, the GSM-R priority (MLPP) is mapped towards this function. This will enhance the functions existing in Control Telephony Function to interwork with PSTN/PLMN when the ISDN trunk supports the MLPP stan- dard.
The existing function handles three priority levels:
Emergency, Priority, and Routine which use the FRL/TCM values 7, 6, and 5 respectively. A normal/administrative call will not have any priority (that is; the FRL/TCM value is set to 0 by default).
This is mapped towards the MLPP priority as shown in the following table:
Type of call |
External TCM/CSI |
Protection level |
MLPP |
Priority level |
ABB |
Normal call |
0 |
0 |
NA |
NA |
|
3 |
0 |
Routine |
4 |
||
Administrative call |
4 |
0 |
Priority |
3 |
|
Routine control call |
5 |
5 |
Immediate |
2 |
** |
Priority control call |
6 |
6 |
Flash |
1 |
*# |
Emergency control call |
7 |
7 |
Flash override |
0 |
## |
With no priority is set to "Normal call" IE, no MLPP IE is sent with the call.
Information Handling for Incoming Calls
In addition to priority, UUI information is received for incoming calls. This is used to display additional information about the caller, for example; train number and role. To be able to show this information on the phone, the UUI must be converted to ASCII, added in the name field, and displayed on the phone. In
addition to the name, the priority value is added if received at the end of the name. See the following figure:
In addition to the display on the phone, the same string is sent as correlated data on CSTa3 in the deliv- ered event. If MiCCE is used, this string is mapped to the associated data so that this can be handled in the application.
Information Handling for Outgoing Calls
