How to Configure a base station controller(BSC) in GSM
If you are interested to learn how to configure a BSC in a GSM network, then you use this step-by-step BSC configuration process to become familiar with BSC configuration process and procedures. Although this article aims for GSM BSC, but it will help you to get a concrete grasp of BSC configuration in general, irrespective of any mobile communication system standards.
No matter which vendor’s BSC you are going to configure, you will always need to configure the following parameter in general. So the following BSC data configuration process will give you and much detail insight on how to configure a GSM BSC. In real world you have to configure the following four types of configurations:
Configuring the BSC (BM/TC Separated)
- Configuring BSC Global Data
- Configuring the BSC Devices (BM/TC Separated)
- Configuring BSC Links
- Configuring the BSC Clock (BM/TC Separated)
BSC global data configuration
This global configuration parameter is needed regardless of the capacity of your BSC and these data present the basic identity of a BSC. The global data configurations can be further categories into the following three:
- BSC attributes
- Configuring SS7 signaling points
- Configuring OSP to subracks.
During the intial phase of a BSC configuration you have to configure a few basic attributes and the rest of the attributes need to be default . The folliwng basic attributes, more or less, you need to configure.
MOD BSCBASIC: Name=”BSC001″,
Configuring the SS7 Signaling Points
This configuration paramenters set the connection path between a BSC and a MSC. In this part of the configuration you have to select origination signaling point (OSP) and destination signaling point(DSP) of a BSC.If there is no direct physical link between the OSP and DSP, you have to configure signaling transfer point(STP). Before staring this configuration you need to have get you DSP list from the NSS engineers. Execute the following three commands in your BSC.
Step 1 Run the ADD OPC command to configure an OPC.
Step 2 Run the ADD N7DPC command to configure a DPC.
Step 3 Run the ADD STP command to configure an STP.
Configuring the Subrack-OSP Mapping
This portion of the BSC global configuraiotn will make the logical connection between BSC borads and the OSP so as a BSC subrack can be specified by a OSP from the NSS end. Run the following command once you know which subrack to connect with which OSP.
Configure the BSC devices
The following type of configurations you need to perform.
Adding GBSC cabinet– a GBSC can be added as a remote or as a local. When a GBSC cabinet is placed on the MSC side, it is called remote cabinet, otherwise it is local. The commend for adding a GBSC is ADD BSCCAB
Adding GBSC subracks– add GEPS and GTCS when you are done with configuring ss7. The command for adding GEPS and GTCS is ADD BSCSUBRACK
Configure the power distribution box
The command for adding power module to the BSC is ADDPWR( subrack 0, management subrack 0, power box type: normal.)
Configure BSC boards
Use the ADD BRD command to add all the BSC borads. When you are adding E1T1 board, you can also configure the E1 number if you already know which E1 to connect, otherwise you can do it later once you are sure of the number of E1.The command for adding E1 is SETE1T1
Configure BSC EAC
Once BSC can be configured with only one EAC. It collects analog, Boolean and alarm threshold information and repot it to the Local maintenance terminal. Command for adding EAC is ADD EAC.
Configure the subrack communication links
This start communication links between GMPS and GEPS, between GEPS or between GTCS. By default the fully connected communication links between subracks are configured when you configure a subrack. A maximum of not more than three subrack communication links can be established between two subracks. But, ideally only two communication links are configured between two subracks-one is active link and the other is standby.
Configure BSC Links
This links are responsible for communication within BSC(Ater interface) and between MSC and BSC(A interface). The Ater infaces links are responsible for signaling transmission between the GMPS/GEPS to GTCS.If GTCS is configured on the MSC side, the Ater connection path, signaling link and OML must be configured. When GTCS is on the BSC side, only the Ater connection path need to be configured. The command for configuring the Ater connection path is ADD ATERCONPATH
Ater connection path scripts:
ADD ATERCONPATH: BMSRN=0, BMSN=14, BMPN=0, TCSRN=3, TCSN=14, TCPN=0; ADD
ATERCONPATH: BMSRN=0, BMSN=14, BMPN=1, TCSRN=3, TCSN=14, TCPN=1;
Ater OML script: command ADD ATEROML
ADD ATEROML: ATERPIDX=0, TSMASK=TS0-0&TS1-0&TS2-1&TS3-1&TS4-1&TS5-1&
TS27-0&TS28-0&TS29-0&TS30-0&TS31-0; ADD ATEROML: ATERPIDX=1,
Note: TS=Time Slot number
Ater Signaling Link configuration: command ATERSL
ADD ATERSL: ATERPIDX=0, TSNO=7, TNMODE=TRRS, CGST=90, CGET=60, WS=16;
A interface links configuration
A interface links configuration includes the configuration of E1T1 and SS7 signaling link.
A interface E1T1 configuration script: ADD AE1T1: SRN=3, SN=16, PN=0, STCIC=0, DPCGIDX=0, ALLTSTYPE=ALLCIC;
A interface SS7 configuration script: ADD N7LNK:
SERVICEMODE=SEPERATE, ATERPIDX=0, ASN=16, APN=0, ATSMASK=TS1-1,
ATERTSMASK=TS8-1, SLC=1, SLCSEND=1, DPC=H’c1, STPC=H’d1, LKRATE=64K, STFLG=NO;
Configuration BSC clock
BSC clock configuration consists of configuring the line clock for GTCS and GMPS and the 8k reference clock for the GTCS,GEPS, GMPS and the system clock. The complete script of BSC clock configuration is as follows:
Line Clock For GTCS: ADD LINECLK: SRN=3, SN=16, LINENO=LINE0, PN=0;
8K Reference Clock For GTCS: MOD SCUCLK: SRN=3, RefClk=LINE_CLOCK;
Line Clock For GMPS: ADD LINECLK: SRN=0, SN=14, LINENO=LINE0, PN=0;
System Clock:ADD CLKSRC: SRCTYPE=LINE0, SRCSUBTYPE=8K_HZ, PRIORITY=4;
8K Reference Clock for GMPS: MOD SCUCLK: SRN=0, RefClk=GGCU_BACK;
8K Reference Clock for GEPS: MOD SCUCLK: SRN=1, RefClk=GGCU_FACE;
This ends the basic configuration of a BSC. After this basic configuration you need to check the alarms for any misconfiguration or any other configuration related issues. Once you are done with your basic BSC configuration you can start adding BTS on your BSC. To add a BTS in a BSC you need to be sure that the physical connection path between a BSC and a BTS has been setup and there is no bit error rate in the Abis link.