GPRS (Standard Packet Radio Assistance) signifies an evolution of the GSM common, enabling details transmission in packet mode and delivering higher throughputs as when compared with the circuit-switched mode. This evolution is usually offered under the designation of two.5G to stage out that it is a changeover technology in between 2G and 3G.
The GPRS community architecture reuses the GSM community nodes these kinds of as MSC/VLR, HLR, and BSS. New community nodes have been released for the transport of packet details. These nodes are the gateway GPRS assist nodes (GGSN) and serving GPRS assist nodes (SGSN). The sub community shaped by the SGSNs and the GGSNs is identified as the GPRS core community. In order to reuse the GSM nodes, new interfaces have been defined in between the GSM community nodes and the unique aspects of the GPRS core community.
GPRS community has the following interfaces
1. SGSN – The SGSN is the node that is serving the MS it is responsible for GMM. It provides packets to the MSs and communicates with the HLR to receive the GPRS subscriber profile. It manages the registration of the new cell subscribers in order to hold a record of their LA for routing uses. The SGSN can be related to one or various BSSs.
two. GGSN – The GGSN provides inter doing work with external packet details networks (PDNs). It may well be joined to one or various details networks. It is related with SGSNs through an IP-based GPRS spine community. The GGSN is a router that forwards incoming packets from the external PDN to the SGSN of the resolved MS. It also forwards outgoing packets to the external PDN. The PDN is the external set details community to which is related the GPRS community. An example of a PDN is the Internet community.
3. HLR – The HLR is a databases that contains, between other items, packet domain subscription details and routing information.
4. Mobile switching heart/customer area registers (MSC/VLR) – The MSC coordinates the placing up of phone calls to and from GSM buyers and manages GSM mobility. The MSC is not straight associated in the GPRS community. It forwards circuit-switched paging for the GPRS-attached MSs to the SGSN when the Gs interface is current.
five. BSS – The BSS ensures the radio link in between the cell and the community. It is responsible for radio obtain management. The BSS is composed of two aspects: the BTS and the BSC. The BTS integrates all the radio transmission and radio reception boards. The BSC is responsible for the management of the radio channels. The BSC has switching abilities that are made use of for circuit-switched phone calls and can also be made use of for GPRS site visitors.
6. EIR – The EIR is a databases that contains terminal identities.
Just one of the main GPRS attributes is that a actual physical link is set up in uplink only when the MS wants to deliver continual details to the community and in downlink only when the community wants to deliver continual details to the MS. This actual physical link is unveiled in one path as soon as the sending entity has no additional details to deliver. Diverse allocation strategies for radio useful resource (RR) management have been defined in order to multiplex various MSs on the very same actual physical channel.