27-12-2012, 02:21 PM
Project on Industrial Training in BSNL Silchar
1Industrial Training.pdf (Size: 348.32 KB / Downloads: 42)
Introduction
Telecommunication is the transmission of signals over a distance for the purpose of communication. In modern times this process almost always invokes the use of electromagnetic waves by transmitter and receiver. But in the earlier years it also involved the use of drums and visual signals such as smoke, fire, beacons, semaphore lines and other optical communications.
NETWORK architecture
PCM:-
The E10B system has been developed for 30 channels PCM operation but it can also handle 24 channels.
URM (Multiplex Connection units):-
A multiplex connection unit URM is the PCM connection interface between E10 exchange and distant connection unit (URAD). The MRS modulus in the URM provides for the connection of 2.048 Mbps PCM links from distant URS. The MRS modules in the URM provide for the connection of 2.048 Mbps.
ETA (Frequency sender-receiver unit):-
The frequency sender-receiver unit ETAS form part of connection unit URS
Functions:
Reception of multifrequency (MF) signaling.
Generation of usual tones
Setting up of conference call connections using the conference circuit
MR (Multiresistor):-
The multiresistor is responsible for the setting up and releasing of calls.
Functions:
It takes control of calls and on-hook condition of subscribers and trunk circuits.
Controls the setting up and releasing of connections between two subscribers by switching network.
Controls the various signals and tones
Tx (Charging unit):-
The charging unit calculates the charge of each call
The charging unit (TX) operates under the control of the MR
TX receives metering pulses from trunk circuits
It controls the sending of tones
It sends subscriber account to OMC
It sends detailed sending message to OMC
SWITCHING:-
In telecommunication networks a switch is a device that channels incoming data from any of the multiple input ports to the specific out part that will take the data towards the intended destinations.
CIRCUIT switching Versus PACKET switching:-
A network path can be used exclusively for a certain duration by two or more parties. The type of switching is known as CIRCUIT switching and is really a dedicated and continuously connected path for its duration. Today an ordinary voice phone call generally uses CIRCUIT switching.
Broad Band
BSNL is the process of commissioning of a word class, multi-gigabit, multiprotocol, convergent, IP infrastructure through national internet backbone-II that will provide the convergent services through the same backbone and broadband access network.
The broadband service will be available on DSL technology (on the same copper cable that is used for connecting telephone) on a country wide basis spanning 198 cities.
In terms of infrastructure for broadband services NB-II would put India at per with more advanced notion.
The services that would be supported includes
Always on broadband access to internet for residual and business customers.
Content based services.
Video multicasting.
Video on demand.
Interactive gaming
TECHNICAL capability:-
The broadband service will be given through the state of art multi-protocol level switching (MPLS) based IP infrastructure, which is designed to provide reliable routers to cover all possible distribution within or outside the country
Layer 1 of the network will consist of a high speed backbone comprising of 24 powerful core routers connected with high speed 2.5 Gbps link. The routers are located on national DWDL network interfacing at STM 16 optical level to provide high transmission speed