1. TOPICS
 GPRS
overview.
 GPRS Architecture.
 GPRS Flow.
 TDC Implementation.

2. GPRS OVERVIEW
 GPRS
(General Packet Radio Service) is a
packed based communication service that
allows data to be sent and received across
a mobile telephone network.
 GPRS
 GPRS
uses Packed Switch Data.
is a step toward 3G and is often
referred as 2.5G.

3. Salient Features of GPRS
 Always
 New
on Connectivity.
and Better Application.
 Reduced
 Billing
GSM operator Cost.
based on volume of data
transferred.

4. Services
 Multimedia
messaging service (MMS).
 Internet
applications for smart devices
through wireless application protocol.
 Push
to talk.

5. GPRS Terminals
 Class
A
MS supports simultaneous operation of
GPRS and GSM services.
 Class B
MS able to register with the network for
both GPRS & GSM services
simultaneously. It can only use one of the
two services at a given time.
 Class C
- MS can attach for either GPRS or GSM.

6. GPRS Architecture

7. 13. Cancel Location
20. Cancel Location
14. Cancel Location Ack
21. Cancel
Location Ack
12. Update Location
15. Insert Subscriber Data
HLR
16. Insert Subscriber Data Ack
Old
MSC
/ VLR
26. GMM Attach Accept
9. IMEI Response
I
8. IME
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1. G I, MC
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(TM
Radius
Server
GGSN
n
Mobile
Station
(MS)
o
ati
oc
23. Ins. Sub
Data Ack
17. Update Location
Ack
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ate
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27. G
ns
MM A
e
Com ttach
plete
22. Insert
Subscriber
Data
Old
SGSN
19. Update
Location
GPRS
Combined
Attach
Procedure
18. Location
Update Request
25. Location
Update Accept
28. TMSI
Reallocation
Complete
10
. IM
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Re I Ch
qu
e
11
es ck
. IM
t
E
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se
DHCP
Server
MSC / VLR
DNS
Server
EIR

8. PDP
Context
Activation
Old
SGSN
Old MSC /
VLR
HLR
MSC / VLR
2. DNS Query
(APN)
Mobile
Station
(MS)
1. Activate PDP Context
(APN)
SGSN
3. DNS Response
(GGSN IP Address)
DNS
Server
10. Activate PDP Context
Accept
4. Create PDP context
request (PAP, CHAP,
PDP request)
9. Create PDP context
Response
7. DHCP Address
Request
8. DHCP Address
Response
GGSN
5. Radius Authentication
Request (PAP, CHAP)
6. Radius Authentication
Response
DHCP
Server
Radius
Server

9. CDR FIELDS USED FOR CHARGING
SGSN
GGSN
GGSN, Charging ID
Record Sequence Number
IMSI, IMEI
APN
PDP Type
Opening Time, Duration
Closing Reason
Diagnostics
List of data volumes
Location Area Code
Routing Area Code
Cell ID
SGSN Change

10. CAUSES FOR CDR CLOSURE
PDP Release
Volume
(MB)
Tariff
Change
3.0
Volume
limit
2.5
2.0
CDR 1
CDR 4
1.5
CDR 3
1.0
CDR 2
0.5
17
18
19
20
Time
Limi
t
21
Time
(Hrs)
Combined

11. SPLITTING OF CDRS
Off-Peak
Peak
Off-Peak
PDP Context
Merged CDR
Merged CDR
Merged CDR