General Packet Radio Services(GPRS)

GPRS GSM

GPRS GSM-Drawbacks Circuit switching is used. Complete traffic channel is allocated to user for complete call period. In circuit switched services, billing is based on the duration of the connection.

GPRS-Introduction GPRS Packet switching offer better utilization of the traffic channels. A channel will only be allocated when needed and released immediately after transmission of packet. With this principle, multiple users can share one physical channel. In order to address the inefficiency, General Packet Radio Service(GPRS) have been developed.

GPRS-Advantages GPRS It offer higher data transmission rate of 171 kbps. Improves utilization of radio resources. Multiple user can share one channel at a time. Volume based billing. Shorter access time.

GPRS Network Architecture GPRS GPRS uses existing GSM for voice. To provide data services new network node need to be introduced as an upgrade. 1. SGSN(Serving GPRS Support Node) 2. GGSN(Gateway GPRS Support Node) These nodes known as GPRS support nodes. Support nodes provide data delivery and routing of data packets between MS and data network. GPRS Support Nodes

 SGSN is at same level as MSC.  SGSN perform following tasks  Packet switching  routing  mobility management  authentication and charging  SGSN processes registration of new mobile subscriber.  Location register of SGSN stores location information and user profile of all GPRS users registered with the SGSN.  SGSN is at same level as MSC.  SGSN perform following tasks  Packet switching  routing  mobility management  authentication and charging  SGSN processes registration of new mobile subscriber.  Location register of SGSN stores location information and user profile of all GPRS users registered with the SGSN. GPRS Support Nodes GPRS 1. SGSN

 Interface between GPRS backbone network and external packet data networks.  GGSN’s functions is similar to router in LAN.  It convert GPRS packets coming from SGSN into appropriate packet data protocol format like internet.  Interface between GPRS backbone network and external packet data networks.  GGSN’s functions is similar to router in LAN.  It convert GPRS packets coming from SGSN into appropriate packet data protocol format like internet. GPRS Support Nodes GPRS 2.GGSN

GPRS GPRS architecture

GPRS architecture and interfaces MS BSSGGSNSGSN MSC UmUm EIR HLR/ GR VLR PDN GbGb GnGn GiGi SGSN GnGn

GPRS protocol architecture apps. IP/X.25 LLC GTP MAC radio MAC radio FR RLC BSSGP IP/X.25 FR UmUm GbGb GnGn L1/L2 MS BSSSGSNGGSN UDP/TCP GiGi SNDCP RLC BSSGP IP LLCUDP/TCP SNDCP GTP

How voice and data is separated? GPRS When voice or data traffic is originated at the subscriber terminal, it is transported over the air interface to the BTS, and from BTS to BSC in same way as a standard GSM Call. BSC require a software upgrade, as well as the installation of a new piece of hardware called a packet control unit(PCU) for GRPS. The PCU directs the data traffic to the GPRS network and can be separate hardware element associated with the BSC.

How voice and data is separated? GPRS BSC MSC SGSN GGSN PCUPCU

GPRS- Mobility Management GPRS GPRS attachment GPRS detachment Location Management

GPRS attachment process GPRS

GPRS- Detach process GPRS