Transcript What is GPRS? - PNGCS | Welcome!

Presentation by Papua New Guinea
Telecommunication & Radiocommunication
Technical Authority (PANGTEL)
For:
PNG COMPUTER SOCIETY ANNUAL
SEMINAR, 4th November 2008
Presenter : Gabriel NAKAU(assisted by Mathew
Wari)
Operations Department (PANGTEL)
What is GPRS?
•This is one of the wireless systems
developed after digital TDMA and CDMA
systems which are classified as B2G
•others are EDGE, HSCSD, iDEN, PHS and
RTT
What does GPRS stand for and
what is it?
• GPRS (General Packet Radio Service) is
a mobile data service available to users of
GSM mobile phones. It is often described
as "2.5G", that is, a technology between
the second and third generations of mobile
telephony.
Continue……
• It provides moderate speed data transfer,
by using unused TDMA channels in the
GSM network.
• The theoretical limit for packet switched
data is 171.2 kbit/s (using 8 time slots and
CS-4 coding). A realistic bit rate is 30–80
kbit/s, because it is possible to use max 4
time slots for downlink.
GPRS Air Interface.
(When we are talking “Radio”, we are already talking: there is an “Air
Interface!”)
• GSM not always efficient to support data traffic
• GPRS is solution-provide more efficient packetbased data services at higher data rates.
• GPRS has same basic ‘air interface’ as GSM
• a 200KHz channel divided into eight time slots.
• However, it defines 4 diff. ch. coding schemes
• CS-1 to CS-4 with diff. data rates.
Most common coding scheme
• For packet data transfer is coding scheme
2(CS-2)
• Enables a given time slot to carry data @
transmission rate of 13.4kbps
Advantage of GPRS
• Use of packet-switching technology
• Enables multiple users to share air
interface resources
• Users feel their services to be “always on”
GPRS-related data traffic and
control signaling
• Though GPRS uses basic structure as
GSM, it introduces new logical channel
types for Packet Common Control
Channel (PCCCH) and for Packet
Dedicated Control Channel (PDCCH)
Comparison of the control and traffic
channels between GSM and GPRS…
Channel
GSM
•CCH (one logical
GPRS
•PCCCH (four
channel)
logical channel)
Broadcast Channel
Dedicated control
channel
•BCCH
•DCCH
•PBCCH
•PDCCH
•PACCH
•PTCCH
Dedicated traffic
channel
•FACCH
•DTCH
•FACCH
•PDTCH
Common Control
Channel
GPRS Network Architecture
RF air
interface
BTS
BSC
MSC/VLR
SMSC
HLR
Packet
Control Unit
(PCU)
SGSN
SGSN
GGSN
Charging
Gateway
Function
PDN
Billing
Therefore,….
• GPRS is primarily for data communication
and not for voice communication.
• GPRS communicates using TCP/IP
protocol similar to the internet.
• GPRS device IP addresses are not
accessible from the internet due to
firewalls.
Regulation Consideration
• PANGTEL ensures relevant frequency is
allocated
• Monitors interference if any, to adjacent
channel
• Ensures equipment deploy in the systems
are in compliance to standard ITU/ETSI
Recommendations
Licensing Requirement
• Spectrum
• Equipment type approval if different
• Agreement between interest
groups(wanted to use GPRS services) &
GSM Operators
Regulatory consideration
• The radio network capacity needed for the
General Packet Radio Service (GPRS) in
coexistence with circuit switched services and
the admissible quality of service for mobile
Internet users is presented.
• Since the GPRS is to be integrated into the GSM
infrastructure, a number of physical channels
has to be made available to GPRS used as fixed
and on-demand packet data channels (PDCH).
Benefits
•Efficient - GPRS mobile devices only use the GSM network
when data is transferred. The GSM connection is not
dedicated to each user, therefore it can be shared with many
users resulting in efficient use of the network.
•Fast - GPRS gives speeds of up to 5 time faster than GSM.
GPRS offers maximum data rates of 56Kbps (down) and
14.4kbps (up), however this is shared bandwidth therefore
actual data rates are potentially lower.
•Payment based on data usage - Billing is not based on
time, but on the amount of data actually transferred.
Way Forward Summary…
• Technology is available
• Provisions in current GSM License
allowed to explore/provide
• Regulator is always available and ready to
assist as long as matter is within
legislative framework & subject to Gov’t
policies.
Source: William C.Y.Lee Wireless & Cellular TelecommunicationsThird Edition & PANGTEL Resources.
And Thank you…