GPRS

1. SOFTCOPY OF THE SEMINAR TOPIC ON
“GPRS”
PRESENTED BY :
Mahendra Kumar Mallick
REGD NO. 080203023
6th SEM
ELECTRONICS & TELECOMMUNICATION
BARAPADA SCHOOL OF ENGINEERING &
TECHONOLOGY,BARAPADA, BHADRAK.
BATCH-2008-2011

2. INTRODUCTION
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
 After initial ‘log-on’, user is permanently connected to
end service
 Network resources only used when information ready to
be exchanged

3. What is GPRS
 GPRS is a new set of GSM-bearer
services that provide packet mode
transmission within the GSM network &
interconnects with external packet data
networks.

4. GPRS Network

5. NEED FOR 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

6. How Does GPRS Work?
When a user turns on a GPRS device, typically it
will automatically scan for a local GPRS
channel. If an appropriate channel is detected,
the device will attempt to attach to the network.
The SGSN receives the attach request, fetches
subscriber profile information from the
subscriber’s HLR node, and authenticates the
user. Ciphering may be established at this
point.

7. GPRS Architecture
 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, e-mail, ftp,..)
 The setup time is negligible – less than a second

8. GPRS Architecture
Continue….
 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.
 1 GSM-burst .In 1 burst 114 databits
 So in 8 bursts 8*114=912 databits.
 As We know that a GSM-frame takes 4,615 ms.
The maximum speed for gprs is then
(912)/(4,615.10-3) = 197617 bits per second.
Division by1024 because 1 kbit=1024 bits. So
(197617)/(1024) = 192 kbit/s.

9. Applications of GPRS
 CHAT
 TEXTUAL AND VISUAL INFORMATION
 STILL IMAGES
 MOVING IMAGES
 DOCUMENT SHARING/
COLLABORATIVE WORKING
 AUDIO
 JOB DISPATCH
 CORPORATE EMAIL
 INTERNET EMAIL
 VEHICLE POSITIONING

10. Advantages of GPRS
 Always-On Connection
 Faster Data Transfer Rates
 Robust Connectivity
 Broad Application Support
 Security Support

11. PACKET TRANSFER
-GGSN decapsulates and sends to PDNs.
-A laptop connects with a GPRS-capable handset.
-The handset communicates with GSM base station.
-Base station sends the GPRS packets to SGSN.
-SGSN encapsulates packets
-Handset location information is updated in other
GSM components, such as HLR.
-SGSN sends encaps. packets to GGSN.

12. PACKET TRANSFER

13. CONCLUSION
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.