GPRS Network composition and interface
GB Port: SGSN through the GB port and base station BSS, for mobile MS Services. Establish a connection between SGSN and Ms through the Logical Control Protocol LLC, providing mobility management (location tracking) and security management functions. SGSN completes the protocol conversion between MS and SGSN, i.e. backbone network uses IP protocol to convert into SNDCP and LLC protocols, and provides MS authentication and registration functions.
GN Port: SGSN through the GN Port and GGSN, through the GPRS Tunneling Protocol (GTP) to establish a channel between SGSN and external data network (X.25 or IP) to achieve the interconnection between MS and external data network.
GS mouth: For SGSN to MSC/VLR send address information, and from the MSC/VLR to receive paging requests, to achieve packet-type business and the association of non-grouped business.
GR Port: HLR Save GPRS user data and routing information (IMSI, SGSN address), each IMSI also contains packet data protocol PDP information, including PDP type (X.25 or IP), PDP address and its QoS level and routing information.
GI mouth: GGSN through the GI port to achieve the GPRS network and external Data Network (PDP) interconnection. GGSN is actually two Internet gateways, GPRS itself belongs to IP domain network, GI port support X.25 and IP protocol. Viewed from the PDN network GGSN,GGSN can be seen as a router connected to the PDN network. The GGSN contains routing information for connecting GPRS users, and provides channels for the PDU of the external data network to be delivered to Ms. Through GGSN and GPRS network interconnection packet Data network PDN, can be PSPDN network, at this time, GPRS support ITU-T X.121 and ITU-T E.164 numbering Scheme provides X.25 virtual circuit and quick selection of X.25, also supports x.75 protocol connection between networks, or Internet network, based on IP protocol, GPRS supports TCP/IP header's compression function in IP datagram transmission mode.
GD Port: Sms_gmsc, Sms_inmsc and SGSN indirect port. Through this interface, SGSN can receive short message, and transfer it to MS, SGSN and SMS Service center-GMSC, through GD interface to complete the short message service on GPRS
GP Mouth: GPRS network indirect port. Using GP interface interconnection among different GPRS networks, the abbreviations are composed of gateways and firewalls.
Drx |
Non-continuous receive |
Em |
Extended measurement |
Gprs |
General Packet Radio Service |
Gsm |
Global Mobile Communication System |
Llc |
Logical Link Control |
Mac |
Media access Control |
Mm |
Mobility Management |
Ms |
Mobile Station |
Pacch |
Packet along-Path control channel |
Pagch |
Packet Access permitted Channel |
Pbcch |
Packet Broadcast control channel |
Pccch |
Packet public control channel |
Pdp |
Packet Data Protocol |
Pdu |
Grouped data units |
Pdch |
Packet data channel |
Pdtch |
Packet Service Channel |
PLMN |
Public Land mobile Network |
Ppch |
Packet Paging channel |
Prach |
Packet Random access Channel |
PSDN |
Packet Switched Data network |
Ptcch |
Group Time Advance Channel |
Rr |
Wireless Resources |
Rlc |
Wireless Link Control |
SI |
System Information |
SGSN |
Service GPRS Support node |
Sndcp |
Subnet-dependent Convergence protocol |
TBF |
Temporary flow identification |
TFI |
Temporary flow identification |
Tlli |
Temporary logical link recognition |
Tqi |
Temporary queue recognition |
USF |
Uplink status Tag |