GSM

1. Gb over IPGb over IP
Network Operations- Committed for Excellence Gb over IP

2. Gb over IPGb over IP
Network Operations- Committed for Excellence Gb over IP

3. GB Over IP:-
Gb over IP offers Internet Protocol (IP) as a transport method in the transmission network. IP can
replace Frame Relay (FR) networks as the transport medium in the Subnetwork Service layer.
Network Service Control Protocol Data Units (PDU) are incapsulated within the User Datagram
Protocol (UDP) datagrams when the IP transport medium is in use.
When IP is used instead of FR, packet based traffic does not go through the circuit based Pulse
Code Modulation (PCM) network. IP enables building an efficient transport network for IP based
services, and helps to reduce the transmission costs.
Gb over IP is a license-based application software. The license sets a limit to the number of
PCUs to which IP NSEs can be configured
Network Operations- Committed for Excellence Gb over IP

4. Network Operations- Committed for Excellence Gb over IP

5. The BSC provides Gb interface towards the General Packet Radio Service (GPRS) core
network (Serving GPRS Support Node, SGSN). In the BSC, the Gb interface protocol
software is implemented in the Packet Control Unit (PCU) plug-in unit, located in each Base
Station Controller Signalling Unit (BCSU).
The IP transport can be used in parallel with FR under the same BSC and Base Station
Controller Signalling Unit (BCSU). One Network Service Entity (NSE) and each PCU always
uses either one, IP or FR transport. Inside one BCSU, separate PCUs can use different
transmission media. In the BSC, there is always one local IP endpoint per PCU.
The operator can use the SEG-specific BTS radio network object parameter transport type
(TRAT) to select the transport type (IP or FR) of the Network Service Entity Identifier (NSEI)
which the BTS/SEG will use.
Network Operations- Committed for Excellence Gb over IP

6. Network Operations- Committed for Excellence Gb over IP

7. In Frame Relay, the user builds the Gb interface in two phases: first the Frame Relay
bearer channels are created, then the NS layer. In IP, only the NS layer needs to be
configured. The BSC then builds the BSSGP virtual connection automatically when the
user enables GPRS in a segment.
Packet Control Unit
Packet Control Unit's IP address is configured in the platform. The IP address determines
the type of the IP endpoint (IPv4 or IPv6) in NSE and what type of IP packets it can
receive. An NSE can only have one type of an IP address.
Network Service Virtual Link (NS-VL)
Network Service Virtual Link (NS-VL) is an IP endpoint in SGSN, which is configured in
BSC's NSE. From BSC's point of view, SGSN's IP endpoint is called a remote IP endpoint.
An IP endpoint (local or remote) is identified by an UDP port and an IP address.The local
IP endpoint in PCU may serve several remote IP endpoints inside one NSE. With the IP
sub-network, an NS-VL may be established by administrative means (static configuration)
or by auto-configuration procedures (dynamic configuration). In dynamic configuration, you
can only create one NS-VL per NSE in the BSC. If the SGSN has more IP endpoints in
NSE, the BSC will create the remote IP endpoints to the NSE automatically.
Network Operations- Committed for Excellence Gb over IP

8. Network Service Entity (NSE)
Network Service Entity (NSE) has an end-to-end significance across the Gb interface. The
peer NSEs on the BSS side and the SGSN side are identified by the same NSEI value. NSE
identifies a group of NS-VLs in the NS layer and a group of BSSGP Virtual Connections
(BVCs) in the BSSGP layer.
One NSE per PCU is supported. Within one NSE a maximum of four NS-VLs are supported
in PCU1 and sixteen in PCU2.
Network Operations- Committed for Excellence Gb over IP

9. Benefits of Gb over IP
• Gb over IP reduces transmission costs by using IP capacity instead of frame relay (FR)
capacity.
• Gb over IP offers the possibility to use an efficient IP subnetwork for IP based services.
• Gb over IP simplifies network management. For example, the restrictions of Frame
Relay do not need to be taken into account anymore. In addition, dynamic IP
configuration provides an easy way to configure the IP connection.
Capacity
IP brings more transport capacity into Gb interface. However, Gb over IP license
needs to be taken into account, since it can restrict the number of PCUs that can
use Gb over IP.
Network Operations- Committed for Excellence Gb over IP

10. Restrictions
• Gb over IP requires support from both BSC and SGSN.
• The maximum number of local endpoints is one. The maximum number of remote
endpoints is 4 with Packet Control Unit 1 (PCU1), and 16 with PCU2.
• The type of the IP address can be either IPv4 or IPv6 in one NSE.
Network Operations- Committed for Excellence Gb over IP

11. Requirements for GB Over IP
Software requirements for Gb over IP
Network element Software release required
BSC S11.5 or later
Nokia Flexi EDGE BTSs No requirements
Nokia UltraSite EDGE BTSs No requirements
Nokia MetroSite EDGE BTSs No requirements
Nokia 2nd Gen. BTSs No requirements
Nokia Talk-family BTSs No requirements
Nokia PrimeSite BTSs No requirements
Nokia InSite BTSs No requirements
MSC/HLR Not applicable
SGSN SG3 or later
Nokia NetAct OSS4 or later
Network Operations- Committed for Excellence Gb over IP

12. Hardware requirements for Gb over IP
Network element Hardware requirements
BSC For BSCi and BSC2i,
BSC660TRX an additional LAN panel and
new cabling are required for
connecting Gb interface to
external LAN switch and edge
router. BSC3i has LAN
connections cabling, switches
and panels by default. All
BSC PCUs must have
Ethernet interface cabling.
BSC3i-1000TRX No requirements
BTS No requirements
TCSM No requirements
Network Operations- Committed for Excellence Gb over IP

13. Redundancy:-
The PCU is configured into the BCSU unit. According to the N+1 redundancy principle,
there is one extra BCSU/PCU unit in the BSC. The additional unit is used only if one of
the active units fails.
One logical PCU has two 10/100BaseTx Ethernet interfaces in each PCU board. These
allow the connection to the LAN switches (internal in BSC3i; external in BSC2i) that
provide the interface for an optimised way of transporting packet switched traffic via IP
pipe. The IP traffic runs through one Gb over IP interface; the other interface is used only
for redundancy purpose if the active interface fails.
With Gb interface over IP, both LAN interfaces (0 and 1) can be used
The LAN interface's duplex speed is fixed to auto negotiation mode.
Network Operations- Committed for Excellence Gb over IP

14. GB Over IP creation in BSC:-
Step 1:- Disable the GENA & EGENA for the BTSs.
Step 2:- Delete the NSVCIs and Bearer channels
Step 3:- Check that the license covering GB over IP has been installed (W7I).
ZW7I: LIC, FULL: LIC=<license code>:;
Step 4:- Check the GB over IP feature state (W7I).
ZW7I: FEA, FULL: FEA=7;
Step 5:- Assign the IP address for PCU in all the BCSUs with (ZQRN)
ZQRN :< unit type>,<unit index>:<plug-in unit type>,<plug-in unit
index>:<interface name>:<ip address>,<L/P>,<DEL>:<net mask
length>:<state>:<mtu>;
Step 6:- Create Default Gateway for all the PCUs with (ZQKC)
ZQKC:<unit type>,<unit index>:<plug-in unit type>,
<plug-in unit index>:<destination IP address>,
<netmask length>:<gateway IP address>:<route type>;
Network Operations- Committed for Excellence Gb over IP

15. Step 7:- Create Packet Service Entity (PSEI) with (ZFXA)
ZFXA:PSEI=<packet service entity identifier>,
BCSU=<base station controller signaling unit>,
PCU=<packet control unit>;
Step 8:- Create the network service virtual link (NS-VL) with (ZFXK)
ZFXK:NSVLI=<network service virtual link identifier>,NAME=<network
service virtual link name>,NSEI=<network service entity
identifier>,PSEI=<packet service entity identifier>: LPNBR=<local UDP
port number>,PRE=Y:RIP=<remote IP address>,RPNBR=<remote UDP
port number>;
Step 9:- Check the creation and state of the NS-VL (FXI)
ZFXI:NSVLI=<network service virtual link identifier>;
Network Operations- Committed for Excellence Gb over IP

16. Example:-
1. Check the License feature in BSC
ZW7I:FEA,FULL:FEA=7;
2. Assign the IP address for PCU
ZQRN:BCSU,0:PCUS,1:IFETH0:131.230.42.22,L;
3. Assign the Default Gateway for PCU
ZQKC:BCSU,0:PCUS,1::131.230.42.2;
4. Check the IP address assignment
ZQRI:BCSU,0:PCUS,1;
5. Creation of PSEI
ZFXA:PSEI=24,BCSU=0,PCU=1;
Network Operations- Committed for Excellence Gb over IP

17. 6. Creation of NSVLI
ZFXK:NSVLI=2,NAME=MAIN_CH_02,NSEI=1,PSEI=24:
LPNBR=50000,PRE=N:RIP=”192.168.0.2”,RPNBR=50000,RDW=1,
RSW=1;
7. Check the States of NSVLI
ZFXI:NSVLI=2;
Network Operations- Committed for Excellence Gb over IP