PRESENTATION. BHARAT SANCHAR NIGAM LTD.HIMANSHU EC 08L068T H

SEM.

INTRODUCTIONWHAT IS BSNL COMPANYS PROFILE PRODUCT AND SERVICES TYPES OF EXCHANGES LAYOUT OF EXCHANGES CALL PROCESSING TESTING AND DETECTION OF FAULTS

BHARAT SANCHAR NIGAM LTD.

BSNL is the largest telecom operator in India On October 1,2000 the Department of Telecom Operations, Government of India became a corporation and was christened Bharat Sanchar Nigam Limited (BSNL). Service is being provided through 32,000 electronic exchanges.

BHARAT SANCHAR NIGAM LTD. (Cont.)Over 2.5 lakh km of Optical Fiber Cable used The Telephone infrastructure alone is worth about Rs. 1,00,000 crore (US $ 21.2 billion) Today with a 37 million line capacity, 99.9% of its exchanges are DIGITAL

PRODUCTS AND SERVICESBSNL connects four corners of the country It provides world class facilities round the clock

PRODUCTS AND SERVICES (Cont.)Cellular Service Basic Telephone Services Internet ISDN Intelligent Network Wireless In Local Loop Leased Lines

TYPES OF EXCHANGESThere are many types of exchanges like: OCB E-10B SEIMENS C-DOT

OCB-283WHAT IS OCB ? OCB means Organ Control Bhersion which is a French word. Alcatel of France has developed this DIGITAL System in 1991(R-11 ver.)

Salient Features Of OCB

It supports both analog and digital signal. The call processing program is distributed over different control organs of the system and is stored in ROM/RAM of the units. The system is made up of only 35 types of cards The system has automatic recovery feature when serious fault occurs in control station Back up unit brings back exchange to its normal functioning.

Specifications.

It is digital switching system; maximum of 2048 PCMs can be connected. The system supports all the existing signaling system e.g. MF (R2) for E10B, CAS, CCS7. The traffic handling capacity of the system is huge depending on the traffic, 200,000 subscribers or 60,0000 circuits.

Main Divisions Of OCB283

MDF Room. Exploitation Room. Switching Room. Power Room.

MDF ROOMWHAT IS MDF ROOM MDF stands for Main Distribution Frame. It is divided into two parts : VDF HDF

MDF ROOM (Cont.)

This room is used to distribute the subscribers call according to his request. The distribution frame provides easy and flexible interconnection, isolation point for testing, protective devices used for safety of exchange equipment etc. All lines are coming from subscribers, non exchange lines, telex lines and analog junction lines are meeting here.

MDF ROOM (Cont.)

One side of MDF is Exchange side and other is called Line Side. MDF is a link between Exchange and Subscribers. It helps in deciding that whether the fault is internal or external.

MDF ROOM (Cont.)TRANSMISSION MEDIA Twisted Pair: Two wires each having its own insulation (low frequency) Coaxial cable: To connect subscribers with exchange (high frequency). Optical Fiber Cable: To connect two exchanges.

Switching Room

The hardware equipment of the OCB 283 consists of a set of control (multiprocessor) station SM. It consists of Racks that has CARDS fitted in it. RACKS SMC : Main Control Station SMA : Auxiliary Equipment SM SMT : PCM trunk SM SMX : Switching Matrix SM SMM : Maintenance SM

Switching Room (Cont.)CARDS

Types Of Cards.There are four types of cards : For analog signal: TABAF, TABASE. For digital signal: TABND, TADPB.

TABAF card is for STD PCO Subscribers. TABASE card is for local subscriber. TABNP card is for basic ISDN.

Switching Room (Cont.)

SMC: Main Control Station

It consists of MR, MQ, TR, TX, PC, GX, which helps, in call processing.

(SMA): Auxiliary Multiprocessor Station It is used for Tone generation, CCITT 7 signaling management, Conference call.

Switching Room (Cont.)

(SMT): Trunk Multiprocessors Station Provide terminations of a maximum of 128 PCM from trunks, CSED and CSND. (SMX): Switching Multiprocessor Station Provide connection between subscribers, subscriber to junction, junction to junction Subs., Fault and alarm processing (SMM A and B) Maintenance Station It works as hot stand.It has got two mirror unique hard disks of 1.2 Gb capacities.

Exploitation Room

Exploitation Room(Cont.)

Also known as Operational and Maintenance Room (OMR). All the operations are done through system software by operating different commands over there. Computers present in the room are having Software's like DOT-SOFT etc. These Computers have all the records, facilities of subscriber.

Call Processing

Call Processing

Off Hook Condition. Feeding Dial Tone. Digit Receiving. Digit Analysis. Release Tandem Call. Power Supplies and Ringers.

Power Plant Of Exchange

Power plants are designed for continuous handling of constant load. The main exchange requires two types of supplies : The first one is 48 V DC supply mainly for switch room. The second one is 220V AC supply for switch room mainly for computer peripheral devices.

OTHER REQUIREMENTS FOR OCB FUNCTIONING:

AIR CONDITIONERS. MICROPROCESSORS. BATTERY AND POWER SUPPLY. POWER ROOM. GENERATORS. TEMPERATURE CONTROLLER. HUMIDITY CONTROLLER. FIRE DETECTORS AND EXTINGUISHERS. EARTHING CONDUCTORS. RECTIFIERS

Subscriber facilitiesThe E-10B system offers a number of facilities to its subscribers. Hotline Detailed billing Absent service Barred access Malicious call tracing Outgoing only subscribers Incoming only subscribers Abbreviated dialing Conference call Automatic alarm call

COMPARISON BETWEEN OCB-283 AND E-10 B :OCB PCMs 384 Subscribers 49000 Traffic(ERLONG) 4000 CCS#7 NO ISDN NO E-10B 2048 200000 25000 YES YES

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