Transcript GPRS
GPRS
Muhammad Al-khaldi
215313
Sultan Al-Khaldi
236437
Outline:
What is GPRS?
GPRS Handset Classes.
Classes of GPRS services.
Benefits of GPRS.
GPRS Network Components.
Simple GPRS Architecture.
IP Addressing.
Enhanced Data Rates for GSM Evolution.
GSM Evolution for Data Access.
Summary.
What is GPRS?
GPRS stands for General Packet Radio
Service.
Allows data to be sent and received
across a mobile telephone network.
Step toward 3G.
It is often referred to as 2.5G.
GSM and GPRS different networks
working in parallel.
What is GPRS?
GPRS combines mobile access with
internet protocol (IP).
It is packet based network technology.
Send and receive data as text, graphics
and video.
GPRS is based on modulation technique
known as GMSK (Gaussian minimum-shift keying).
GPRS Handset Classes:
Class A:
• Have 2 transceivers.
• allow them to send / receive data and voice at the
same time.
• takes full advantage of GPRS and GSM.
Class B:
• can send / receive data or voice but not both at the
same time.
GPRS Handset Classes:
Class C:
• Allows one means of connectivity.
• Like GPRS PCMCIA card in a laptop.
Classes of GPRS services:
traffic priority classification :
Precedence Class: An application can be assigned
a Precedence Class 1, 2 or 3. If an application has a higher
precedence (1) than another (3) then its traffic will be given a
higher priority.
Delay Class: Applications can request a delay classes
which guarantee an average and 95% delay for 128 octet and
1024 octet packet size. There are 4 classes, 1 being the
fastest.
Classes of GPRS services:
Reliability class: Applications can request differing
levels of reliability for its data depending on its tolerance to data
loss.
Throughput Class: There are 2 distinctions in
class, peak and mean. Peak throughput class is used mainly for
bursty transmissions. Mean is the average data transfer rate
over a period of time measured in octets per hour.
Benefits of GPRS:
Speed: at around 56–115 kbps
Always on connectivity: data can be sent or
received immediately as it is produced .
The system does not require establishing a
connection .
New and Better applications: such as video
conferencing straight to your desktop or mobile
device.
Benefits of GPRS:
GSM operator Costs: it allows GSM
providers to add value to their business
at relatively small costs.
Extremely efficient use of radio
bandwidth: this is because it is packet
based service.
GPRS Network Components:
GPRS is not a completely separate
network from GSM.
Packet Control Unit (PCU): used to
control a packet switched data.
Base Station Controller (BSC): it is part
of GSM network.
GPRS Network Components:
Serving GPRS Support Node (SGSN): it
performs the following tasks:
• Routing.
• Handover.
• IP address assignment.
• Verification and collection of billing data.
GPRS Network Components:
Gateway GPRS Support Node (GGSN):
provide the following:
• Works as a gateway.
• Works as a router.
• Works as a firewall.
• Confirms user details with RADIUS (Remote
Authentication Dial In User Service) servers for
security.
GPRS Network Components:
GPRS Tunneling Protocol (GTP): The
main function is to make connectivity
between the SGSN & GGSN
• GTP sits on the top of TCP/IP
• responsible for the collection of mediation and
billing information.
Home Location Register (HLR): a
database that contains subscriber
information
Simple GPRS Architecture:
IP Addressing:
There are three different ways:
• Fixed IP addressing: IP to every handset (the
1st way).
IP Addressing:
• Dynamic IP addressing:
The 2nd way is by giving every GGSN an IP
and every handset belong to this domain. (like
LAN)
The 3rd way (also dynamic) the IP is given by
RADIUS.( like dial up)
IP Addressing:
Enhanced Data Rates for GSM
Evolution:
EDGE provides Enhanced GPRS
(EGPRS).
Increased data rates with GSM
compatibility.
Still 200 KHz bands; still TDMA.
In addition to GMSK EDGE uses 8PSK.
8-PSK modulation: 3 bits/symbol give 3X
data rate.
Enhanced Data Rates for GSM
Evolution:
EDGE can carry data speeds up to 384
kbps.
It is anther step to 3G,it reffered as
2.75G.
Shorter range (more sensitive to
noise/interference).
Enhanced Data Rates for GSM
Evolution:
Introduces a new technology not found
in GPRS, Incremental Redundancy.This
increases the probability of correct
decoding.
EDGE takes the cellular community one
step closer to UMTS.
GSM Evolution for Data Access:
Summary:
GPRS is 2.5G.
It have many advantages.
the main components of GPRS is
It have two types of IP addressing:
• SGSN
• GGSN
• Fixed IP addressing
• Dynamic IP addressing.
Summary:
EDGE is 2.75G
Carry data speeds up to 384 kbps.
It uses both GMSK &8PSK.
One step closer to UMTS.
Thank you
Any Question