GPRS stands for General Packet Radio Service. It is a standard for wireless communication that enables the transmission of data packets between mobile devices and the internet. GPRS is part of the GSM (Global System for Mobile Communications) standard and represents an evolution beyond traditional circuit-switched data services. Key features of GPRS include: Packet-Switched Technology: GPRS operates on a packet-switched network, where data is broken into packets for transmission. This is in contrast to circuit-switched networks used for voice calls. Always-On Connectivity: GPRS provides an "always-on" data connection, allowing users to stay connected to the internet without the need to establish and terminate connections for each data session. Efficient Data Transmission: The packet-switched nature of GPRS allows for more efficient use of network resources, as data packets are transmitted independently, and network capacity is dynamically allocated. Data Rates: GPRS offers data rates ranging from 56 kbps to 114 kbps, depending on factors such as network conditions and device capabilities. While considered relatively slow by modern standards, GPRS was a significant improvement over earlier data services. Compatibility: GPRS is backward-compatible with GSM networks, allowing devices to seamlessly switch between circuit-switched (voice) and packet-switched (data) modes. Applications: GPRS laid the foundation for various mobile data services, including mobile internet browsing, email, and basic applications. It was a precursor to more advanced technologies like 3G (UMTS) and 4G (LTE). Billing Structure: GPRS introduced a billing model based on the volume of data transmitted rather than the duration of the connection. Users were billed according to the amount of data they consumed, encouraging the development of data-centric applications. While GPRS was widely used in the early 2000s, it has largely been superseded by faster and more advanced technologies like 3G, 4G, and 5G. These newer standards provide significantly higher data rates, lower latency, and improved support for multimedia applications. Despite its diminished role in modern networks, GPRS played a crucial role in paving the way for the mobile data services we use today.

1. By Eng:
Waleed El-Safoury
Copyright © 2020 Waleed Elsafoury

2. • SMS
• FAX
• E-mail
• Internet
• Intranet
• Multimedia

5. 1.Circuit-Switching
2.Message-Switching
3.Packet-Switching

6. • Like Telephone connection
• Both source and destination has nothing but data TX.
• Connection is done after connecting several points between
source and destination
• After setup connection speed is constant during TX

7. • Best for real time applications
• Reverse Charging
• Call Redirect
• Incoming Calls only
• Outgoing Calls Only
- The system offer full channel connection regardless
to traffic amount
- Both source and destination must have the same
protocol
- If the destination or connection points are busy
source may wait a lot until it is free

8. • Store-and-Forward Message Switching
• It is not important to both source and destination to be connected
at the same time
• It is not necessary to establish a full connection between them
• If an error happened it is not necessary to re-transmit the
message as each point it pass has a copy of it

9. •It offers better BW usage
• It has smaller setup time
• If there is more than one path we can select the free one
- User can not control reception time
- can’t be used for real time

10. • Each message is divided into packets and then transmitted
• Each packet has source and destination information and
control data
• Each packet has its own connection and path
• Packets may arrive not in order so it should be re-arranged

11. • It is fastest switching method
• It is not important to both source and destination to be
connected at the same time
• Both source and destination may not have the same protocol
• As packets are small it is easier to re-transmit
• As packets are small it use paths for less time

13. GSM UMTS

14. • GSM900 / E-GSM
• GSM1800 (DCS1800)
• GSM1900 (PCS1900)
• GSM-R

15. GSM Phase1:
- digital transmission
- Data transmission was also defined with transmission rates of
0.3 to 9.6 kbit/sec
- includes only a few supplementary services
GSM Phase2:
- Half-rate speech were considered
- All networks and terminal equipment of phase 2
were compatible to the networks and terminal
equipment of phase 1

16. • Enhanced Full Rate Speech
• multi-mode terminal equipment (satellite roaming)
• Internet access
• High Speed Circuit Switched Data
• General Packet Radio Service
• Enhanced Data Rates for the GSM Evolution

18. • Add new modulation technique 8PSK

19. Downlink Peak Data Rate
(Typical Deployment)
Downlink Peak Data Rate
(Theoretical Maximum)
GSM 9.6kbps 9.6kbps
GPRS 40kbps 171kbps
EDGE 120kbps 473kbps

20. • 9.6 kbps are possible

26. Supports both calls and data with manual switching between them

27. Supports both calls and data with automatic switching between
them but not at the same time with calls priority

28. Supports both calls and data simultaneously

30. MSC GMSC
BSC
VLR
PCU SGSN GGSN
CS-Domain
PS-Domain

33. 1. Screening (Firewall)
2. Routing
3. Billing
4. Protocol translation
GGSN 9811

34. •Routing & Switching
•mobility management
• security
• Authentication
• Ciphering
• Billing
- The cause of early ciphering in the GPRS network
•increase transmission security
• it will not be necessary to reconfigure all existing Base
Transceiver Stations
SGSN 9810

35. • Channel request and assignment
• Power control
• Handover decision
• Retransmission decision

36. BSC&
PCU

38. Idle State
Ready State
Standby State
Attach
Timer
Data
Transfer
Detach
Timer

39. Location area 1
Routing area 1
Routing area 2
Routing area 3

43. 0 1 2 3 4 5 6 7
Frame = 4.615 msec
Slot = 0.577 msec = 156.25 bit

44. 3 181 + 40 + 0000
USF Header + Data BCS
228 bits
228 bits
Convolutional
encoder
6 450
USF payload
456 bits
181 bit/20 msec
= 9.05 Kbps

45. 6 268 + 16 + 0000
USF Header + Data BCS
294 bits
Convolutional
encoder
12 444
USF Payload
456 bits
268 bit/20 msec
= 13.4 Kbps
12 576
USF Payload
588 bits
Remove 132
bits

46. 6 312 + 16 + 0000
USF Header + Data BCS
338 bits
Convolutional
encoder
12 444
USF Payload
456 bits
312 bit/20 msec
= 15.6 Kbps
12 664
USF Payload
676 bits
Remove 220
bits

47. 12 428 + 16 +
USF Header + Data BCS
456 bits
Convolutional
encoder
12 444
USF Payload
456 bits
428 bit/20 msec
= 21.4 Kbps