Ocb Exchange Ppt By Aadyant(india)

CONTENTS Introduction Salient

features of OCB-283 exchange General Architecture of OCB-283 Subscriber access unit Trunk & Junction connection unit Switching network Control units Time base generator Operation & Maintenance unit conclusion

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INTRODUCTION OCB-283is digital switching system which supports a variety of comm. Like basic talephony,ISDN,interface to mobile comm., data comm. Etc. The first OCB-283 exchange of R-11 version was commissioned in FRANCE & Beijing, CHINA. The first OCB-283 exchange come to INDIA in 1993,subsequently the system has been upgraded and currently ,R-20 was fully validated in January 1994. There after time to time up gradation to this OCB-283 SYSTEM was upgraded to R-25.

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Salient features of OCB-283 

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It is digital switching system with an angle “T” stage switch a maximum of

2048 PCM can be conducted. Its supports both ANOLOG and DIGITAL subscribers. OCB-283 has a double recovery feature. Various units of 0CB-283 system are connected over token ring. This enables fast exchange of information & avoid complicated links. The charge account of subscriber are automatically saved in a disk once in a day , this avoid lose of revenue in case of total power supply failure. The exchange can be managed locally or from an NMC through 64 KBPS links. All the control units are implemented on same type of hardware. This is called a station. The ocb-283 systems are made up of 35 types of cards. The system has modular structure . The expansion can be very easily carried out by adding necessary hardware & software. The Environment requirement of the system is very flexible. The system can work at temp. 5-45°C ; through optimum temp. is 22°C.

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Subscriber Access Unit Subscriber access unit (CSN) is so designed that they can be equipped with analog or digital subscriber or both. The cards for both are different but they can be equipped in any slot of the shelf. CSN can be placed either in EXCHNAGE switch room or at a remote location. CSN is known as CSNL or CSND. Architecture OF CSN: The CSN have one BASIC RACK and up to 3 Extension Racks. The architecture can be divided into parts:

DIGITAL CONTROL UNIT(UCN):1: Control & connection unit (UCX) 2: Auxiliary equipment processing group (GTA)

Function Of Control Units:  

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Multi resister (MR):- Call handler setup and release of call. Translator (TR):- Translation of digits, databanks of subscriber & circuits in files. Marker (MQ):- Message distribution between common control & connection units. Charger (TX):- Computing the charges of a call, keeping meter. Matrix System Handler (GX):- Process & make connection in switching matrix on the order from MR or MQ. Common Channel signaling Network Controller:- Manage the CCS#7 network for signaling.

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TRUNK & JUCTION CONNCTION UNIT(SMT) 

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This is also known as PCM trunk control station. This unit is an interface between PCM junction coming from other exchange & switch. The current version of SMT in India is SMT 2G. In each SMT 2G , there are 8 modules & in each module SAB PCMs, in single SMX there are 16 PCMs. Thus there are 128 SMT BRANCH 68030. 2G. SMT 2G is built around microprocessor A PCM INTERFACE

PCM INTERFACE

SMT A SMT B

A

SAB BRANCH B

SMX B

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Switching Network The switching matrix in OCB-283 is ‘T’ system. It is made up of: 1-Host switching matrix (SMX) 2- Branch selection & amplification (SAB) function The host switching matrix consists of two identical branches A & B. This is implemented on the hardware units known as 2048×256 matrix control station (SMX) Matrix(0) 

2048×256 Matrix(1)

2048×256 Matrix(3)

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CONTROL UNIT (SMC) ARCHITECTURE OF STATION(SMC):Main processor unit

Main Coupler (CMP)

Secondary Processor Unit (PUS) 1

Common Memory

Secondary Coupler 1 (CMS)

Secondary Coupler 4 (CMS)

Secondary Processor Unit (PUS) 4

Specific coupler 7

Time Base Generator (STS)

Time base generator is required to synchronize PCM links connection units like CSNL,SMT & SMA etc. The time base is generated by synchronization and time base station (STS) & distributed to the branches of the switching network. These branches then redistributed the time base to above mentioned connection units along with LRs.

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Operation & Maintenance Unit (SMM)  

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SMM station in ocb-283 performs the O & M functions. The SMM station has full duplicate hardware SMM A & SMM B. For both SMM there are two mirror image hard disks of 1200 MB capacity. SMM dialogue with all SMCs over MIS token ring. There are up to 4 alarm reception ring for handling exchange alarms.

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Conclusion OCB-283 is a versatile digital switching system assigned to meet all types of modern communication trends. The system has novel features like “automatic denoting”. Due to these features and because of existing ETB expertise, the system is especially suitable for Indian network. The system provides a large no. of subscriber facilities. The System requires no human intervention & an inherent capability to supervise all the functional units and keep them updated. All these features made the OCB-283exchange efficient and user friendly.

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ANY QUESTION?

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