General Packet Radio Services(GPRS) is a packet-based wireless communication service that promises data rates from 56 up to 114 Kbps and continuous connection to the Internet for mobile phone and computer users. The higher data rates allow users to take part in video conferences and interact with multimedia Web Sites and similar applications using mobile handheld devices as well as notebook computers. GPRS is based on the Global System for Mobile (GSM) communication and complements.
In theory, GPRS packet-based services cost users less than circuit-switched services since communication channels are being used on a shared-use, as packets are needed basis rather than dedicated to only one user at a time. It is also easier to make applications available to mobile users because the faster data rate means that middleware currently needed to adapt applications to the slower speed of wireless system are no longer be needed. As GPRS has become more widely available, along with other 2.6G and 3G services, mobile users of Virtual Private Networks (VPN) have been able to access the private network continuously over wireless rather than through a rooted dial-up connection.
GPRS Also Complements Bluetooth, a standard for replacing wired connections between devices with wireless radio connections. In addition to the Internet Protocol (IP). GPRS supports X.25, a packet-based protocol that is used mainly in Europe. It is an evolutionary step toward Enhanced Data GSM Environment (EDGE) and Universal Mobile Telephone Service (UMTS).
Services Offered
GPRS extends the GSM Packet circuit switched data capabilities and makes following services possible:
- SMS messaging and broadcasting
- Always on internet access
- Multimedia Messaging Services (MMS)
- Push to talk over Cellular Phone (PoC)
- Instant Messaging and presence wireless village
- Internet Applications for smart devices through Wireless Application Protocol (WAP)
- Point-to-Point (P2P) Service
Hardware
Devices Supporting GPRS are divided into three Classes:
Class A
Can be connected to GPRS service and GSM service (Voice,SMS) using both at the same time. Such devices are known to be available today.
Class B
Can be connected to GPRS service and GSM service, but using only one or the other at a given time. During GSM service, GPRS service is suspended. and then resumed automatically after the GSM service has concluded. Most GPRS mobile devices are Class B.
Class C
Are connected to either GPRS service or GSM service. Must be switched manually between one or the other service.
The following table summarises some possible configurations of GPRS and Circuit switched data services.
Cells and Routing Areas
The geographic coverage area of a GPRS network is divided into smaller areas known as cells and routing areas, as shown in Figure 24−14. A cell is the area that is served by a set of radio base stations (BSs). When a GPRS MS wants to send data or prepare to receive data, it searches for the strongest radio signal that it can find. Once the mobile scans for the strongest signal and locates the strongest BS, it then notifies the network of the cell it is receiving the strongest and selects it. At this point, the mobile listens to the BS for news of incoming data packets.
Data Transfer
Once the MS has attached to a SGSN and activated a PDP address, it is now ready to begin communicating with other devices. For example, a GPRS mobile is communicating with a computer system connected to an X.25 or IP network. The other computer may be unaware that the MS is, in fact, mobile.
From this point onward, they are routed based on their original (internal) header. Using tunneling within GPRS solves the mobility problem for the packet networks and helps to eliminate the complex task of protocol interworking. Mobile IP also makes use of tunneling to route packets to mobile nodes. In mobile IP, packets are only tunneled from the fixed network to the MS. Packets flowing from the mobile to fixed nodes use normal routing. GPRS, by contrast, uses tunneling in both directions.
Some Applications for GPRS
Chat. Can be distinguished from general information services because the source of the information is a person with the chat protocol, whereas it tends to be from an Internet site for information services. The information intensity, the amount of information transferred per message, tends to be lower with chat, where people are more likely to state opinions than factual data. In the same way as Internet chat groups have proven to be a very popular application of the Internet, groups of like−minded people, so−called communities of interest, have begun to use non-voice mobile services as a means to chat and discuss.
Textual and Visual Information. A wide range of content can be delivered to mobile phone users, ranging from share prices, sports scores, weather, flight information, news headlines, prayer reminders, lottery results, jokes, horoscopes, traffic, location−sensitive services, and so on. This information does not necessarily need to be textual — it may be maps or graphs or other types of visual information.
Moving Images. Over time, the nature and form of mobile communication is getting less textual and more visual. The wireless industry is moving from text messages to icons, picture messages to photographs, blueprints to video messages, movie previews being downloaded, and on to full−blown movie watching via data streaming on a mobile device.
Audio. Despite many improvements in the quality of voice calls on mobile networks, such as Enhanced Full Rate (EFR), they are still not broadcast quality. In some scenarios, journalists or undercover police officers with portable professional broadcast−quality microphones and amplifiers capture interviews with people or radio reports that they have dictated and need to send this information back to their radio or police station. Leaving a mobile phone on or dictating to a mobile phone would not give
sufficient voice quality to enable that transmission to be broadcast or analyzed for the purposes of background noise analysis or voice printing, where the speech autograph is taken and matched against those in police storage.
Internet E−mail. Services come in the form of a gateway service where the messages are not stored or mailbox services in which messages are stored. In the case of gateway services, the wireless e−mail platform translates the message from SMTP, the Internet e−mail protocol, into SMS and sends it to the SMS Center. In the case of mailbox e−mail services, the e−mails are actually stored, and the user receives a notification on his or her mobile phone and can then retrieve the full e−mail by dialing in to collect it, forward it, and so on.
Technology
|
Download (kbit/s)
|
Upload (Kbit/s)
|
TDMA Timeslots allocated (DL+UL)
|
CSD
|
9.6
|
9.6
|
1+1
|
HSCSD
|
28.8
|
14.4
|
2+1
|
HSCSD
|
43.2
|
14.4
|
3+1
|
GPRS
|
80.0
|
20.0 (Class 8 & 10 and CS-4)
|
4+1
|
GPRS
|
60.0
|
40.0 (Class 10 and CS-4)
|
3+2
|
EGPRS (EDGE)
|
236.8
|
59.2 (Class 8, 10 and MCS-9)
|
4+1
|
EGPRS (EDGE)
|
177.6
|
118.4 (Class 10 and MCS-9)
|
3+2
|
Cells and Routing Areas
The geographic coverage area of a GPRS network is divided into smaller areas known as cells and routing areas, as shown in Figure 24−14. A cell is the area that is served by a set of radio base stations (BSs). When a GPRS MS wants to send data or prepare to receive data, it searches for the strongest radio signal that it can find. Once the mobile scans for the strongest signal and locates the strongest BS, it then notifies the network of the cell it is receiving the strongest and selects it. At this point, the mobile listens to the BS for news of incoming data packets.
Data Transfer
Once the MS has attached to a SGSN and activated a PDP address, it is now ready to begin communicating with other devices. For example, a GPRS mobile is communicating with a computer system connected to an X.25 or IP network. The other computer may be unaware that the MS is, in fact, mobile.
From this point onward, they are routed based on their original (internal) header. Using tunneling within GPRS solves the mobility problem for the packet networks and helps to eliminate the complex task of protocol interworking. Mobile IP also makes use of tunneling to route packets to mobile nodes. In mobile IP, packets are only tunneled from the fixed network to the MS. Packets flowing from the mobile to fixed nodes use normal routing. GPRS, by contrast, uses tunneling in both directions.
Some Applications for GPRS
Chat. Can be distinguished from general information services because the source of the information is a person with the chat protocol, whereas it tends to be from an Internet site for information services. The information intensity, the amount of information transferred per message, tends to be lower with chat, where people are more likely to state opinions than factual data. In the same way as Internet chat groups have proven to be a very popular application of the Internet, groups of like−minded people, so−called communities of interest, have begun to use non-voice mobile services as a means to chat and discuss.
Textual and Visual Information. A wide range of content can be delivered to mobile phone users, ranging from share prices, sports scores, weather, flight information, news headlines, prayer reminders, lottery results, jokes, horoscopes, traffic, location−sensitive services, and so on. This information does not necessarily need to be textual — it may be maps or graphs or other types of visual information.
Moving Images. Over time, the nature and form of mobile communication is getting less textual and more visual. The wireless industry is moving from text messages to icons, picture messages to photographs, blueprints to video messages, movie previews being downloaded, and on to full−blown movie watching via data streaming on a mobile device.
Audio. Despite many improvements in the quality of voice calls on mobile networks, such as Enhanced Full Rate (EFR), they are still not broadcast quality. In some scenarios, journalists or undercover police officers with portable professional broadcast−quality microphones and amplifiers capture interviews with people or radio reports that they have dictated and need to send this information back to their radio or police station. Leaving a mobile phone on or dictating to a mobile phone would not give
sufficient voice quality to enable that transmission to be broadcast or analyzed for the purposes of background noise analysis or voice printing, where the speech autograph is taken and matched against those in police storage.
Internet E−mail. Services come in the form of a gateway service where the messages are not stored or mailbox services in which messages are stored. In the case of gateway services, the wireless e−mail platform translates the message from SMTP, the Internet e−mail protocol, into SMS and sends it to the SMS Center. In the case of mailbox e−mail services, the e−mails are actually stored, and the user receives a notification on his or her mobile phone and can then retrieve the full e−mail by dialing in to collect it, forward it, and so on.
GPRS packet-based services cost users less than circuit-switched services since communication channels are being used on a shared-use, as packets are needed basis rather than dedicated to only one user at a time. Good Job...
TumugonBurahinI think GPRS means General Packet Radio Services...Am I right??
TumugonBurahinYes Raffy your correct!..
BurahinGeneral Packet Radio Services(GPRS) is a packet-based wireless communication service that promises data rates from 56 up to 114 Kbps and continuous connection to the Internet for mobile phone and computer users.
Hope this helps..
GPRS use Packet Mode Technique to transfer data and provides connectivity to Internet.
TumugonBurahinthe faster the data transfer speed. Because GPRS transmits data in packets, the timeslots are not in use all the time, but are shared amongst all users of the network.
TumugonBurahinAs GPRS has become more widely available, along with other 2.5G and 3G services, mobile users of virtual private networks (VPNs) have been able to access the private network continuously over wireless rather than through a rooted dial-up connection.
TumugonBurahin