We can divide GSM System into four components and they are:
· Mobile Station
· Base Station Subsystem
· GPRS Core Network
· Network Switching Subsystem
Mobile Station:
The mobile station (MS) comprises all user equipment and software needed for communication with a Wireless telephone network.
Terminal Equipment:
A device or devices connected to a network or other communications system used to receive or transmit data. It usually includes some type of I/O device.
SIM:
A smart card inserted into GSM telephones that contains the user's telephone account information, and that allows the user to use a borrowed or rented GSM telephone as if it were his or her own.
Base station subsystem:
The base station subsystem (BSS) is the section of a traditional cellular telephone network which is responsible for handling traffic and signaling between a mobile phone and the network switching subsystem.
BTS:
A base transceiver station (BTS) or cell site is a piece of equipment that facilitates wireless communication between user equipment (UE) and a network. UEs are devices like mobile phones (handsets), WLL phones, computers with wireless internet connectivity, Wi-Fi and Wi-MAX gadgets etc.PCU:
The Packet Control Unit (PCU) is a late addition to the GSM standard. It performs some of the processing tasks of the Base Station Controller (BSC), but for packet data.
GPRS Core Network:
The General Packet Radio Service (GPRS) system is used by GSM mobile phones, the most common mobile phone system in the world, for transmitting IP packets. The GPRS core network is the centralized part of the GPRS system. It also provides support for WCDMA based 3G networks
SGSN:
A serving GPRS support node (SGSN) is responsible for the delivery of data packets from and to the mobile stations within its geographical service area.
GGSN:
A network node that acts as a gateway between a GPRS wireless data network and other networks such as the Internet or private networks. GPRS - General Packet Radio Service. An enhancement to the GSM mobile communications system that supports data packets.
Network Switching System:
Network switching subsystem (NSS) (or GSM core network) is the component of a GSM system that carries out call switching and mobility management functions for mobile phones roaming on the network of base stations. It is owned and deployed by mobile phone operators and allows mobile devices to communicate with each other and telephones in the wider Public Switched Telephone Network or (PSTN).
MSC:
Mobile Switching Center (MSC) is the place that provides telephony switching services and controls calls between telephone and data systems. The MSC switches all calls between the mobile and the PSTN and other mobiles.
VLR:
Visitor Location Register (VLR) is a database - part of the GSM mobile phone system - which stores information about all the mobiles that are currently under the jurisdiction of the MSC (Mobile Switching Center) which it serves.
HLR:
A database containing subscriber information files about the subscriber and the current location of a subscriber's mobile station is called home location register.
EIR:
The GSM equipment identity register (EIR) database contains information on the identity of mobile equipment to prevent calls from stolen, unauthorized or defective mobile stations.
PSTN:
The public switched telephone network (PSTN) also referred to as the plain old telephone service (POTS) is the network of the world's public circuit-switched telephone networks. It consists of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables all inter-connected by switching centers which allows any telephone in the world to communicate with any other.
BSC:
A device (or software) that controls the BTS’s within a GSM network. Within Private Mobile Networks one BSC can control and manage the signaling and voice channels for 100 BTS’s.
Abis: The Interface between base station and BSC is called Abis.
0 comments:
Post a Comment