BSNL internship
description
Transcript of BSNL internship
PRESENTED BY : RAJAN MEENAVIIth SEM ECE
08EC071
HISTORY OF BSNL
Firstly post and telegraph department came into existence in 1980.
First exchange in rajasthan was of 25 lines. Control of Ajmer was upto Udaipur, Agra and Ratlam.
In 1985, post and telegraph seperated into two different departments i.e. Department of Post and Department of Telegraph.
HOW SUBSCRIBER REACHES TO EXCHANGE
Each subscriber who wants to contact require handset
The handset divided into two main parts . The line chord is connected to the handset and reach to a black box known a ROSETTE
Through the rosette two wires comes out which is connected with the WINDOW
After that they reach the DP i.e. the DISTRIBUTION POINT
On DP the wires comes in the form of pair . One I DP 20 wires can be connected from different places
DP must be grounded . DP is a box which is installed on a petlar
After DP , there is a cabinet which is in the form of large box and which is kept in a large area which consists of approximately one thousand pair of wires .
And then it connected to the another type of box this is called Main Distribution Frame
WiMAX Highlights
• WiMAX– Worldwide Interoperability for Microwave Access
– Is a certification mark for products that pass conformity and interoperability tests for the IEEE 802.16
– provides wireless data over long distances in a variety of ways, from point-to-point links to full mobile cellular type access
• Speed– Faster than broadband service
• Wireless– Not having to lay cables reduces cost– Easier to extend to suburban and rural areas
• Broad coverage– Much wider coverage than WiFi hotspots
Two forms of wireless service
• Line-of-sight service– Higher frequencies, lots more bandwidth– 30-mile radius
• Non-line-of-sight– A small antenna on a computer connects to the tower– Uses 2 GHz to 11 GHz frequency range– Limited to a 4-to-6 mile radius
• BASE STATION (BS): The BS is responsible for providing the air interface to the MSS.
• ACCESS SERVICE NETWORK GATEWAY (ASN-GW): The ASN gateway typically acts as a layer 2 traffic aggregation points within an ASN. Additional functions include intra-ASN location management and paging, and admission control, caching of subscriber profiles and encryption keys.
• CONNECTIVITY SERVICE NETWORK (CSN): •The CSN provides connectivity to the Internet, ASP, other public networks, and corporate networks. The CSN is owned by the NSP and includes AAA servers that support authentication for the devices, users, and specific services.
WiMAX Applications
• According to WiMAX Forum it supports 5 classes of applications:
1. Multi-player Interactive Gaming.
2. Video Conference
3. Streaming Media
4. Web Browsing and Instant Messaging
5. Media Content Downloads
Broadband Policy-2004
ALTTC/DX/IBB_OV/AKN
10
Broadband connectivity as defined in Broadband policy-2004 is an “always on” data connection that is able to support interactive services including Internet access and has the capability of minimum download speed of 256 kbps to an individual subscriber from the POP of the service provider
Internet v Broadband Sub’s in India
ALTTC/DX/IBB_OV/AKN
11
0
10
20
30
40
2005 2007 2010
Internet Sub’s
Broadband Sub’s
6M3M
18M
9M
40M
20M
Broadband Technologies
ALTTC/DX/IBB_OV/AKN
12
Broadband Technologies
Wireless
3G Mobile
Wireline
Wi-Fi (Wireless Fidelity)
Satellite
DSL (Digital Sub’s Line)
Cable Modem
Optical Fibre Technologies
PLC (Power Line Communication)
WiMAX
OPTICAL FIBER
OPTICAL FIBER
FIBER OPTICAL TRANSMISSION SYSTEM
A Widely Used Communication Medium Based on TIRInformation (Voice, Data Or Video) Is Transmitted In The Form Of Light
FIG. COMMUNICATION THROUGH OPTICAL FIBRE
Jacket
CladdingCore
Cladding
Angle of reflection
Angle of incidence
Light at less thancritical angle isabsorbed in jacket
Jacket
Light is propagated by total internal reflection
Jacket
Cladding
Core
(n2)(n2)
Fig. Total Internal Reflection in an optical Fibre
ARCHITECTURE OF FIBER AND IT’S PRINCIPLE
ADVANTAGES OF FIBER OPTICS
High Speeds – Up To The GigabitsLow InterferenceLarge BandwidthSignals Can Be Transmitted At Larger Distances Without The Need Of RepeatersGreater Resistance To Electromagnetic NoiseNo Crosstalk
GSM Network Architecture
MS
BTS
BTS
BTS
BTS BTS
BTS
BTS
BTS
BSC
BSC
PSTN
VLR
TRAU HLREIR
OMC
SMSC
BC
AUC
VMSC
MSC
Abis
A
OML
CELLULAR MOBILE CONCEPTS WHAT IS A CELL ?
• A base station (transmitter) having a number of RF channels is called a cell
• Each cell covers a a limited number of mobile subscribers within the cell boundaries ( Coverage area)
• Typical Cell Radius Aprrox = 30 Km (Start up)
GSM Services
SERVICE CATEGORIESMain type of telecommunication services: Basic services: Available to all subscribers to a mobile network. e.g. voice telephone calls. Supplementary services: Additional services that are available by subscription only. e.g. Call forwarding.