Submitted to:Ms. Garima Mathur (HOD,ECE)
Submitted by:Vaibhav Bhootna (EC09121)
Company Profile Introduction Services Provided Exchange MDF OCB GSM Conclusion
Type: State-Owned Enterprise Head Quarter's New Delhi Key People: People: Mr. R K Upadhyay (Chairman & MD) MD) Established: Oct 2000 Owner: Govt. Of India
Today, BSNL is the No. 1 telecommunication telecommunicat ion company and the largest public sector undertaking of India and its responsibilities includes improvement of the already impeccable quality of telecom services, expansion of telecom services in all villages and cities
Universal Telecom Telecom Services
Mo bile Telephone Telephone Services Cellular Mobile WLL-CDMA WLL-CDM A Telecom elecom Services Servic es Internet Intelligent Network 3G IPTV VVoIP
Wireless Broadband) Broad band) WiMax (4th Gen Wireless
Equipment which effects interconnection of telephones is known as switching equipment. equipment. The
switching centre, which houses the terminating and switching equipment is called telephone exchange.
1.
All telephone subscribers are served by automatic exchanges.
2. Today’s automatic exchanges uses a pair of computers.
One, running the program that t hat provides services. Second, monitoring the operation of the first, ready to take over in a few seconds in the event of equipment failure.
Various exchanges present in BSNL are: >
C-DOT
>
OCB
>
EWSD
Typical exchange consist of : Switch Room Operations and Maintenance (OMC) Room Input Output processor (IOP) Room Power Plant Room Battery Room Main Distribution Frame (MDF) Room
POWER PLANT :
SWITCHING ROOM :
consists of BM and CM cabinets Switch room consists mounted in standard switch. fastened to a switch switch Room and These cabinets are fastened interconnected by cables.
Main Distribution Frame is a signal distribution frame or a cable rack used in telephony to interconnect and manage telecommunication telecommunication between itself and any number of intermediate distribution distribution frame and cabling from the telephone network it supports
Vertical side Horizontal side
RACK: -On the rack, the tags are situated. One rack is having eight tags. The
counting is done from up (0) to down (7). TAGS: -Each rack consists of eight tags.
1 tag = 4 core 1 core = 4 bunch 1 bunch = 2 line N.E.:-The word NE stands for the ‘NUMBER OF EQUIPMENT’ EQUIPMENT ’.
It is used for testing number number . WEDGE:
Wedge is used as a device for checking the ring. Wedge is placed in jack strips, which is connected to telephone for checking.
HORIZONTAL SIDE:
The horizontal side connected to the underground cable. This cable is having 100 pairs. These pair is distributed when we allot the telephone number to the subscriber . Horizontal side is again subdivided in two parts: One part is connected with the vertical side. Another with the subscriber line by using 100 pair underground
cable.
The new switching systems are based on Stored Program Control concept. The call processing programmers are distributed over different control organs of the system and are stored in ROM/RAM of the units Processor in the control units . Features:
It is a digital switching system. The system supports all the existing signaling system . The system has
‘auto recovery’ feature. When When a serious fault occur in control unit, it gives a message to SMM (operation (operation & maintenance unit).
DC voltage is used because it doesn’t produce any
noise on the line. 48v is efficient to transmit over a long distance and
safe for Telecom Technician and service personnel. Negative Voltage is used to reduce the corrosion from
electro-chemical reactions occurring occurring on a wet telephone wire.
History - Torleiv Torleiv Maseng is regarded as the father of the GSM Technology. - 1989, GSM responsibility was transferred to the European Telecommunications Standards Institute (ETSI) - first GSM network was launched in 1991 by Radiolinja in Finland with joint technical infrastructure maintenance from Ericsson Ericsson..
Global System for Mobile Communication GSM is an ETSI standard for 2G Pan-European digital cellular with international roaming
2G GSM networks operate in the 900 MHz or 1800 MHz bands. •
GSM-900 uses 890 – 915 915 MHz to send information from the mobile station to the base station (uplink) •
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935 – 960 960 MHz for the other direction (downlink),
This system structured hierarchically as shown:
It consist of one administrative administrative region, which is assigned to a MSC(Mobile Switching Center). Each administrative Region Region is made up of at least one Location Area(LA). LA is also called the visited area. An LA consists of several cell groups. Each cell group is assigned to a base station controller(BSC). Cells of one BSC may belong to different LA’s.
Mobile Equipment (ME) Subscriber
Identity Module (SIM) Base Station controller (BSC) Base Station Subsystem (BSS) Mobile services Switching Center (MSC) Home Location Register (HLR) Authentication Centre (AuC) Equipment Identity Register (EIR) Visitor Location Register (VLR) Public Switch Telephone Network (PSTN)
MS refers to the physical phone itself. uniquely identified by the International Mobile Equipment Identity (IMEI) number. Sim is small smart card that is inserted into the phone and carries information specific to the subscriber •
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carry out radio communications communications between the network and the MS •
handles speech encoding, encryption, multiplexing ( TDMA), and modulation/demodulation •
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allocation of radio channels
frequency administration administration
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power and signal measurements from the MS, •
handovers from one BTS to another •
call routing, call setup, and basic switching functions •
inter-BSC handoffs as well as coordinates with other MSC's for inter-MSC handoffs. •
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gateway between two networks
switch to the Public Switched Telephone Network (PSTN). •
HLR maintains subscriberspecific information such as the MSISDN, IMSI, current location of the MS, roaming restrictions, •
VLR is a database that contains a subset of the information located on the HLR •
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EIR is a database that keeps tracks of handsets on the network using the IMEI handles the authentication and encryption tasks for the network =
MSISDN is Subscriber Telephone Telephone number IMSI (International Mobile Subscriber Identity) MSISDN is a number uniquely uniquely identifying a subscription in a GSM or UMTS network. The MSISDN and IMSI are two important numbers used for identifying a mobile subscriber IMSI is used as key in HLR IMSI is uniquely associated to a SIM
During this summer training period at RTTC RTTC Jaipur , I come to know about the t he various telecommunication telecommunication equipment and technologies used earlier , or which are currently in use such as GSM 3G & CDMA, CDMA , switching systems of OCB & CDOT and data communication systems with Internet Internet nodes , Wi-Fi Wi-Fi equipment, equipment, IP VPN. Basically I have have discussed the GSM and the telephone exchange to give an overview to understand the telecommunication telecommunication system.
