07-11-2012, 02:15 PM
OCB 283 DIGITAL ELECTRONIC EXCHANGE
[attachment=38412]
MTNL A Brief Introduction
On 28th February Mahanagar Telephone Nigam Ltd. was incorporated as a Public Limited Company under the Companies Act, 1956.
The company has been set up to take over the management, control and operation of Delhi Telephone District and Mumbai Telephone District of the Department of Telecommunications and to plan, establish, develop, provide, operate and maintain all types of telecommunication.
Objectives of MTNL
To upgrade the quality of telecom services
To expand telecom
To raise necessary financial resources
To provide new telecommunication services, particularly needed by the business community and public administration such as Cellular Mobile Radio Telephone, Radio Paging, Facsimile Videotex, Teletex, Electronic Mail etc.
To invest in Human Resource Development
To organize and dovetail the training programmes.
OCB 283
OCB 283 is digital switching system
It supports a variety of communication needs like basic telephony, ISDN, interface to mobile communication, data communication etc.
This system has been developed by CIT ALKATEL of France.
The first OCB-283 exchange came to India in1993.
The exchange, which are being supplied to India, belong to R21 version.
Silent Features of OCB 283
digital switching system with single ‘T’ stage Switch , maximum of 2^12 (=2048)
supports both analog and digital subscribers
provides telephony, ISDN, Data communication, cellular radio and other value added services
automatic recovery feature
charge accounts of subscribers are automatically saved in the disc. This avoids loss of revenue in case of total power supply/battery failure.
SUBSCRIBER ACCESS UNITS (CSN)
equipped with either analog or digital subscriber or both
either placed in the exchange switch room or at a remote location
depending on the location, CSN is known as CSNL or CSND and the subscriber shelf is known as local or remote concentrator i.e CNL or CNE.
Architecture of OCB283
Subscriber Access Units (CSNL, CSND, CSED)
Trunks and Junction connection Units (SMT)
Switching Matrix (SMX)
Auxiliary Equipments (SMA)
Control Units (SMC)
Communication multiplexes (MIS & MAS Token rings)
Time base generator (STS)
Operation and Maintenance Unit (SMM)
SAB FUNCTION
Stands for ‘Selection & Amplification of Branches’
role - to generate two sets of LRs in Trans direction with calculation of parity etc.
In case of errors the samples from only the good branches are taken. After automatic testing of the quality of transmission of both the branches by the common control & the faulty bran is withdrawn from the service.
[attachment=38412]
MTNL A Brief Introduction
On 28th February Mahanagar Telephone Nigam Ltd. was incorporated as a Public Limited Company under the Companies Act, 1956.
The company has been set up to take over the management, control and operation of Delhi Telephone District and Mumbai Telephone District of the Department of Telecommunications and to plan, establish, develop, provide, operate and maintain all types of telecommunication.
Objectives of MTNL
To upgrade the quality of telecom services
To expand telecom
To raise necessary financial resources
To provide new telecommunication services, particularly needed by the business community and public administration such as Cellular Mobile Radio Telephone, Radio Paging, Facsimile Videotex, Teletex, Electronic Mail etc.
To invest in Human Resource Development
To organize and dovetail the training programmes.
OCB 283
OCB 283 is digital switching system
It supports a variety of communication needs like basic telephony, ISDN, interface to mobile communication, data communication etc.
This system has been developed by CIT ALKATEL of France.
The first OCB-283 exchange came to India in1993.
The exchange, which are being supplied to India, belong to R21 version.
Silent Features of OCB 283
digital switching system with single ‘T’ stage Switch , maximum of 2^12 (=2048)
supports both analog and digital subscribers
provides telephony, ISDN, Data communication, cellular radio and other value added services
automatic recovery feature
charge accounts of subscribers are automatically saved in the disc. This avoids loss of revenue in case of total power supply/battery failure.
SUBSCRIBER ACCESS UNITS (CSN)
equipped with either analog or digital subscriber or both
either placed in the exchange switch room or at a remote location
depending on the location, CSN is known as CSNL or CSND and the subscriber shelf is known as local or remote concentrator i.e CNL or CNE.
Architecture of OCB283
Subscriber Access Units (CSNL, CSND, CSED)
Trunks and Junction connection Units (SMT)
Switching Matrix (SMX)
Auxiliary Equipments (SMA)
Control Units (SMC)
Communication multiplexes (MIS & MAS Token rings)
Time base generator (STS)
Operation and Maintenance Unit (SMM)
SAB FUNCTION
Stands for ‘Selection & Amplification of Branches’
role - to generate two sets of LRs in Trans direction with calculation of parity etc.
In case of errors the samples from only the good branches are taken. After automatic testing of the quality of transmission of both the branches by the common control & the faulty bran is withdrawn from the service.