Practical Training Ppt

PRACTICAL TRAINING PRESENTATION

PRESENTED BY-MEGHA AGARWAL

2K7-MRCE-ECE-029

Company profile

Nokia Siemens Networks is a leading global enabler of telecommunications services. It is one of the largest telecommunications hardware, software and services companies in the world. It is committed to innovation and sustainability and offers a complete portfolio of mobile, fixed and converged network technologies as well as professional services including consulting and systems integration, network implementation, maintenance and care, and managed services.

GSM Architecture & InterfacesGSM defines 2 interfaces:-

AIR INTERFRACE: - this open interface exists between Mobile station and Base station.

A INTERFACE: - this is between Mobile service switching centre(MSC) and the Base station controller(BSC).In a GSM network, this decentralized intelligence is implemented by dividing the whole network into three separate subsystems:

•Network Switching Subsystem (NSS)•Base Station Subsystem (BSS)•Network Management Subsystem(NMS)

The actual network needed for establishing the call is composed of the NSS and the BSS.

The BSS is responsible for radio path control and every call is connected through the BSS.

The NSS takes care of call control functions.

The NMS in the operation and maintenance related part of the network and it is needed for the control of the whole GSM network. The network operator observes and maintains network quality and service offered through the NMS.

GSM NETWORK

The Base Station Subsystem consists of the following elements:BASE STATION COTROLER (BSC) -It is the central network element of the BSS and is responsible for :

•Connection establishment between the MS and the NSS,•mobility management , •Air and A interface signaling support.

BASE TRANSCEIVER STATION (BTS) - It is a network element maintaining the Air interface. It takes care of:

•Air interface signaling, •Air interface ciphering

TRANSCODER AND RATE ADAPATATION UNIT (TRAU) -It is a BSS element taking care of speech transcoding that is, it is capable of converting speech for one digital coding format to another and vice versa. TRAU is controlled by BTS.

The Network Switching Subsystem consists of the following elements:

MSC (Mobile Switching Centre) – It serves a number of BSS’s (Base Station Subsystem) via the A-interface. An MSC is responsible for call control (set-up, routing, control and termination of the calls), manages the inter-MSC handover and supplementary services, and is responsible for collecting charging/accounting information. It acts as a gateway to other GSM networks and public-switched networks. An MSC acting as a bridge between the mobile network and a fixed network is called a Gateway MSC.

HLR (Home Location register) – It is a “Home Base” of information regarding customers subscribing to a particular operators GSM network. It keeps track of subscriber profile, conditions and whereabouts.

MSCBTSBSC

VLR

HLR

SONOFON

M N

VLR (Visitor Location register) –It is a database with information about mobile users present/active in the network segment served by the MSC.

MSCBTS

BSC

VLR

HLR

SONOFON

M N

AUC - Authentication Centre – It contains the individualsubscriber-identification key (also contained in the SIM), and provides the subscriber data to the HLR and VLR used for authentication and encryption of calls.

AUC

HLR

EIR - Equipment Identity Registration – It stores information about mobile stations in use and may block calls from a MS if the MS is stolen, not type-approved or has faults which may disturb the network. Each MS is identified by a unique International Mobile Station Equipment Identity (IMEI). MSC

EIR

NETWORK MANAGEMENT SYSTEM (NMS) :-

The purpose of the NMS is to monitor various functions and elements of the networkThe functions of the NMS is divided into 4 categories:-

•Alarm monitoring- AM department is responsible for monitoring for power failures, communication line alarms and other performance issues that may affect the network.

•Fault management- The purpose of the fault management is to ensure the smooth operation of the network and rapid correction of any kind of problems that are detected.

•Configuration management- The purpose of this department is to maintain up to date information about the operation and configuration status of network elements.

•Performance management-In performance management, the NMS collects measurement data from individual network elements and stores it in a database to compare the actual performance of the network with the planned performance and detect both good and bad performance areas within the network.

I did my practical training at Global Network Operation Centre (GNOC) department in BHARTI CIRCLE .

NSN, Noida has NOCs for 4 network operators:-•BHARTI•TATA TELE SERVICES LIMITED•AIRCEL•IDEA

BHARTI CIRCLESNSN handles 8 circles :-

•Mumbai •Maharashtra & Goa•Gujarat•Madhya Pradesh & Chattisgarh•Bihar & Jharkhand•Orissa•Kolkata•West Bengal.

AM-BSS

This department is concerned with the monitoring of the BSS of GSM like BTS and BSCs. Each transceiver located on a BTS is called a site. Site down criteria:-Minor- less than 5 sitesMajor- 5-24 sitesCritical- 25 and above

The working of this team is summarized in the following flowchart:-

TOP LEVEL VIEW OF BSCs –

MML SESION

TROUBLE TICKET –

ONLINE CELL OUTAGE

MESSAGES

AM-NSSIt monitors the NSS of GSM network, i.e. it manages the MSCs, GMSCs, HLR, VLR.

It monitors the links and routes which are very important for the connection to exist.

ALARM MONITORING WINDOW

REFLECTION WINDOW

TOP LEVEL-NSS

COMMUNICATOR

ESCALATION MATRIX:-

THANK YOU