 नमस्ते, welcome to the video lecture on GPRS, that is General Packet Radio Service. Learning outcome, at the end of this session, students will be able to evaluate features of GPRS, students will be able to explain GPRS architecture. These are the contents of video lecture. Before starting GPRS topic, pause video for 2 minutes and list all second generation standards for an interesting part. Pause the video for 2 minutes and list all second generation standards. I think 2 minutes are over. The answer is second generation standards includes IS-136, GSM, PDC, IS-94. Three technologies are based on FDMA and TDD. That is multiple access which is used in three technologies FDMA that is frequency division multiple access with time division duplexing and one technology is using CDMA that is code division multiple access. The general packet radio service is an enhancement of the GSM system that makes the use of packet switched data service possible to the mobile user. GPRS is an overlay on top of the GSM or IS-136 physical entities. It extends data capabilities of GSM and provides connection to the external packet data network through the GSM infrastructure with short access time. And it is well suited for non-real-time internet uses such as the retrieval of email, faxes and symmetric web browsing. This data overlay network provides packet data transport at rates of 9.6 kbps. Key feature of GPRS. Packet switching GPRS involves overlaying a packet based air interface on existing circuit switched a network. This gives the mobile user an option to use a packet based data service. Mobile data over GPRS network it uses air interface and infrastructure of GSM to provide mobile packet data service that can support data rates up to 171.2 kbps. Generally data rate is 9.6 kbps and it can be extended to 171.2 kbps. Spectrum efficiency. Packet data simply means that GPRS radio resources are used only when mobile user are actually sending or receiving data. Otherwise same time slots or resources can be provided to a voice signal. Capacity enhancement The actual number of simultaneous mobile data users supported by the system depends on the application and how much data is being transferred. For example, a user want to access web that is a small version of websites. Then data rate depends on the size of that particular web page. Reservation protocol in GPRS. Time slot can be reserved for data access using slotted allow or reservation protocol medium access technique. Security features in GPRS. The security offered by GPRS is similar to that offered by GSM and includes the key security parameters such as anonymity, authentication and confidentiality. You can observe the GPRS architecture. It is using same infrastructure that is used by GSM with some additional equipments like HGSN and GGSN. Let us see function of each component in architecture. The infrastructure is looking same, but actually it is upgraded as equipment in architecture is upgraded to support packet-frista data network. Let's see function of each component in architecture. GPRS mobile station. That is GPRSMS. New mobile stations are required to use GPRS service because existing GSM phones do not handle the enhanced air interface or packet data. A variety of MS can exist including a high-speed version of current phones to support high-speed data access, a new PDA device with an embedded GSM phone and PC cards for laptop computers. These mobile stations are backward compatible for making voice call using GSM. So, mobile station must be upgraded to access or there is a feature or hardware which must be included to support a packet data. So, new hardware or new mobile subscribers are required to access GPRS over GSM architecture. The mobile stations which are previously used for voice call cannot be used to support GPRS application or we cannot run GPRS application mobile phones which are designed to use only voice call. Next component is GPRS base station. Each base station requires the installation of one or more packet control units and software upgrade. The PC use that is packet control unit provides a physical and logical data interface to the base station subsystem for packet data traffic. The BTS can also require a software upgrade but typically does not require hardware enhancement. So, same hardware with upgraded software can be used to support a GPRS. When either voice or data traffic is originated at the subscriber mobile it is transported over the air interface to the base station. And from the base station to the BSC in from the base station to the BSC in the same way as standard GSM call. However, at the output of the BSC the traffic is separated. Voice is sent to the mobile switching center per standard GSM and data is sent to a new device called HGSM via the PCU that is packet control unit over a frame relay interface. Serving GPRS support mode. This is the new component or new equipment which is added mainly to support GPRS applications. Previously it was not present in GSM architecture. So, let us see application or function of serving GPRS support mode. The serving GPRS support mode is responsible for authentication of GPRS mobiles, registration of mobiles in the network, mobility management and collecting information on charging for the use of air interface. Next new component is Gateway GPRS support mode. The Gateway GPRS support mode act as an interface and router to external networks. It contains routing information for GPRS mobiles which is used to tunnel packets through the IP based internal backbone to the current serving GPRS support mode. The GSM also collects charging information connected to the use of the external data networks and can act as a packet filter for incoming traffic. Backbone network. The internal backbone is an IP based network used to carry packet between different GSMs. Tunneling is used between HGSM and GGSM. So, the internal backbone does not need any information about domains outside the GPRS network. Signalling from GSM to the MSC, HLR or EIR is done using SS7 protocol. Location management in GPRS. Let us see the process which includes location management in GPRS. There are various scenarios defined in GPRS to update subscribers location within the network. The first method or the first step, routing area update, intra-HGSM and inter-HGSM. GPRS attach and detach. When user want to access GPRS, then it must initiate GPRS attach procedure and when it want to disconnect, it must initiate detach procedure. Cell update. Only why GAM ready state, that is GPRS mobility management ready state. Next process, mobility management in GPRS. GPRS mobility management are used to keep track of the current location of an MS and to initiate security procedure. GPRS mobility management is a function that is mainly handled between MS and HGSM. The HLR is also involved in mobility management process. As we know in GSM, when mobile subscriber visits a new location, then it must be registered to the HLR and the VLR. That procedure is similar to the mobility management in GPRS. Last part of this video lecture is GPRS applications and services. A wide range of last part of this video lecture is GPRS applications and services. A wide range of corporate and consumer applications are enabled by non-voice or data mobile services such as SMS. Typical GPRS applications include all normal GSM services, but in more efficient and faster. Few applications and services which are supported by GPRS are communications, well-ordered services, e-commerce, location-based applications, vertical applications, advertising. These are the references of the video lecture. Thank you.