1. MIGRATION OF GSM TO GPRS
TECHNICAL SEMINAR PRESENTATION
MIGRATION OF GSM TO GPRS
Presented by
NISHITH RANJAN SAHOO
Roll no: EI
Under the Guidance of
Dr. Partha S. Mallik
Nishith Ranjan Sahoo EI

2. INTRODUCTION MIGRATION OF GSM TO GPRS
GPRS (General Packet Radio Service)
Reuse the existing GSM infrastructure
Introduce packet-switched routing functionality
Better data transfer rates
Low cost and connectivity-oriented
Migration Path to 3G Networks
“Always on” / always connected
Nishith Ranjan Sahoo EI

3. NEED FOR GPRS MIGRATION OF GSM TO GPRS
Existing Cellular networks have problems:
Data Rates too slow – about 9.6 kbps
Connections setup too long & complicated
Proves expensive for bursty traffic utilization
Inefficient resource utilization for bursty traffic
No efficient method for packet transfers
Nishith Ranjan Sahoo EI

4. PACKET-SWITCHED TECHNIQUE VS. CIRCUIT-SWITCHED
MIGRATION OF GSM TO GPRS
PACKET-SWITCHED TECHNIQUE VS. CIRCUIT-SWITCHED
In circuit-switching, resources (e.g. a channel) are allocated to user for duration of connection
Inefficient use of resources
User pays for the whole connection
High QoS: channel maintains real-time connection
In packet-switching, resources are allocated to user only for the time it takes to send each packet
A channel can serve many users
User pays by the packet
Ideal for bursty data connections
Nishith Ranjan Sahoo EI

5. GPRS ARCHITECTURE MIGRATION OF GSM TO GPRS
GPRS = GSM + packet switching. GPRS has the features of a real data network.
Speeds up to 190 kbps (theoretical maximum).
No dial-up modems needed, but direct
connections.
Billing based on sended/received bits, no
telephone ticks.
All applications available (www, , ftp,..).
The setup time is negligible – less than a second.
Nishith Ranjan Sahoo EI

6. GPRS ARCHITECTURE MIGRATION OF GSM TO GPRS
How is the high speed of GPRS realized?
Dynamic assignment of bursts to a user. In GSM 1 burst per user.
In GPRS theoretical maximum of 8 bursts per user.
Sync: 26 bits
000
Data: 57 bits 1 1
Data: 57 bits
000
Nishith Ranjan Sahoo EI

7. MIGRATION FROM GSM TO GPRS
MIGRATION OF GSM TO GPRS
MIGRATION FROM GSM TO GPRS
The migration path from GSM to GPRS requires:
Additional packet switching nodes (routers between the base stations and the mobile switch center).
The existing GSM nodes to be upgraded with GPRS functionality.
Commercial data services to be provided for this a GPRS operator needs to deploy other elements like Access servers and Firewalls.
Nishith Ranjan Sahoo EI

8. GPRS ENVIRONMENT MIGRATION OF GSM TO GPRS Nishith Ranjan SahooEI

9. GPRS ARCHITECTURE : MOBILE STATION
MIGRATION OF GSM TO GPRS
GPRS ARCHITECTURE : MOBILE STATION
GPRS MS includes two components:
MT (Mobile Terminal). Typically a handset used to access the radio interface.
TE (Terminal Equipment). Typically a laptop or a Personal Digital Assistant (PDA).
Three types of MS:
Class-A: Could be attached to both GPRS and other GSM services, and the MS supports simultaneous operation of GPRS and other GSM services.
Class-B: Could be attached to both GPRS and other GSM services, but the MS can only operate one set of services at a time.
Class-C: Could be exclusively attached to one service type at a given time.
Nishith Ranjan Sahoo EI

10. GPRS Architecture Interfaces
MIGRATION OF GSM TO GPRS
GPRS Architecture Interfaces
MSC/VLR
HLR D Gr Gs Gc A Gb Gn Gi
PDN TE TE MT
BSS
SGSN
GGSN Ga R Um Ga Gp Gn
Billing
System
Other PLMN
CGF
SGSN
GGSN Gf
EIR
• CGF(Charging Gateway)
Nishith Ranjan Sahoo EI

11. SGSN – SERVING GPRS SUPPORT NODE
MIGRATION OF GSM TO GPRS
SGSN – SERVING GPRS SUPPORT NODE
At the same hierarchical level as the MSC.
Transfers data packets between mobile stations and GGSNs.
Keeps track of the individual MSs’ location and performs security functions and access control.
Detects and registers new GPRS mobile stations located in its service area
Participates into routing, as well as mobility management functions.
Nishith Ranjan Sahoo EI

12. GGSN – GATEWAY GPRS SUPPORT NODE
MIGRATION OF GSM TO GPRS
GGSN – GATEWAY GPRS SUPPORT NODE
Provides inter-working between PLMN and external packet-switched networks.
Converts the GPRS packets from SGSN into the appropriate packet data protocol format (e.g., IP or X.25) and sends out on the corresponding packet data network.
Participates into the mobility management.
Maintains the location information of the mobile stations that are using the data protocols provided by that GGSN.
Collects charging information for billing purpose.
Nishith Ranjan Sahoo EI

13. GPRS ARCHITECTURE:BACKBONE NETWORK
MIGRATION OF GSM TO GPRS
GPRS ARCHITECTURE:BACKBONE NETWORK
Tunnels of data and signaling messages between GPRS support nodes.Protocol architecture based on the Internet Protocol (IP).
GTP (GPRS Tunneling Protocol) used to tunnel user data and signaling between GPRS Support Nodes.
Two kinds of GPRS backbone Network:
Intra-PLMN backbone network: The IP network interconnecting GSNs within the same PLMN.
Inter-PLMN backbone network: The IP network interconnecting GSNs and intra-PLMN backbone networks in different PLMNs.
Border Gateway handles the packet transfer between GPRS PLMNs.
Nishith Ranjan Sahoo EI

14. GPRS ARCHITECTURE: BACKBONE NETWORK
MIGRATION OF GSM TO GPRS
GPRS ARCHITECTURE: BACKBONE NETWORK
Packet Data Network
Inter-PLMN Backbone Gi Gi Gp
GGSN BG BG
GGSN
Intra-PLMN Backbone
Intra-PLMN Backbone
SGSN
SGSN
SGSN
Nishith Ranjan Sahoo EI

15. PACKET TRANSFER MIGRATION OF GSM TO GPRS Nishith Ranjan SahooEI

16. Packet Data Network(PDN)
MIGRATION OF GSM TO GPRS
PLMN2
PLMN1
BSC
BTS
BSC
BTS
SGSN
SGSN MS
Inter-PLMN
GPRS Backbone Gn
Intra-PLMN
GPRS Backbone Gp
Intra-PLMN
GPRS Backbone
Border
Gateway Gn
Border Gateway Gn
GGSN
SGSN
Packet Data Network(PDN)
Eg.Internet,Intranet Gi
GGSN
Host
Router
Nishith Ranjan Sahoo EI

17. MOBILITY MANAGEMENT MIGRATION OF GSM TO GPRS
Mobility management is the means by which GPRS keeps track of a mobile subscriber location while connected to the Network.
Main concepts :
GPRS mobility management states
GPRS network access.
Attachment.
Location management
Packet Data protocol PDP context
Detachment
Nishith Ranjan Sahoo EI

18. MOBILITY MANAGEMENT STATES
MIGRATION OF GSM TO GPRS
MOBILITY MANAGEMENT STATES
IDLE
GPRS Attach
unreachable mobile
Explicit Detach
GPRS Detach
READY
Timer expiry/ Force STANDBY/ Abnormal RLC condition
reachable mobile
PDU Transmission /Reception
STANDBY
Nishith Ranjan Sahoo EI

19. CONCLUSION MIGRATION OF GSM TO GPRS
The GPRS should cost uses less than circuit-switched services since communication channels are being used on a shared basis and also the packets are need-based rather than dedicated only to one user.
The next stepping stone would be moving towards 3G by implementing EDGE (Enhanced Data rates for Global Evolution),
The GPRS is the key transition phase and is a fundamental requirement for Third Generation Mobile Communications.
Nishith Ranjan Sahoo EI

20. MIGRATION OF GSM TO GPRS
THANK U !!!!!!!!!!!!!
Nishith Ranjan Sahoo EI