Communication has always been an important aspect of human life from stone age to this modern era. However the mode of communication gradually changed with the passage of time. Telecommunication came into existence about 150 year ago. Initially only voice communication was part of telecommunication. Systems were designed keeping in view the voice transmission. It was low capacity, short distance, and purely frequency based analog system. This was know as FIRST generation system. Use of data on this voice network started in SECOND generation systems. Internet, private data transfer, Tele printer, Fax, 9.6 kbps data for defence, were application supported by second generation voice network. This system was designed for voice communication but data was also supported by it. Now in this modern era we had THIRD generation system which is design for Data communication and also support voice on it. It support high speed data communication such as Broad band, Teleconferencing, Video conference, Internet, GPRS, Edge, Core networking and so on.
To meet demand of very high BANDWIDTH due to exponential increase in telephone, mobile, and Data networks, Time Division Multiplexing (TDM) switching technique was used in Telecom Networks .Media such as coaxial cable and microwave were aving their limitation such as limited capacity, disturbance due to atmospheric effect, cost and maintenance problem. OPTICAL FIBER cable were having capabilities to over come hese limitations and has been proved as the best replacement. Use of optical fiber resulted in a revolution in telecommunication transmission.
In analog carrier communication system, the frequency division multiplexing (FDM) method is often adopted to make full use of bandwidth resources of cables and enhance the transmission capacity of the system. It involves transmitting several channels of signal imultaneously in a single cable and, at the receiver end, utilizing band pass filter to filter the signal on each channel according to the frequency difference among the carriers. But this TDM/FDM was not utilizing the complete Bandwidth of optical fibers. This resulted in optical fiber frequency division multiplexing (OFDM). This method can also be used to nhance the transmission capacity of the system .In fact this multiplexing method is very effective in optical communication. Unlike the frequency division multiplexing in analog arrier communication system, optical fiber communication utilizes optical wavelength as single carrier. It divides the low attenuation window of optical fiber (Appendix A) into several channels according to the frequency difference of each wavelength channel. Further, it implements multiplexed transmission of multi channel optical signals in a single fiber. Since some optical components (such as narrow-bandwidth optical filter and coherent laser) are currently not mature, it is difficult to implement ultra dense optical frequency division multiplexing of optical channel. However, alternate channel optical frequency division multiplexing can be implemented based on current component technical level. Usually, multiplexing with larger channel spacing (even indifferent windows of optical fibers) is called optical wavelength division multiplexing(WDM) and WDM in the same windows within a band (C,L…)) with smaller channel spacing is called as dense wave division multiplexing(DWDM) (Appendix B) With the advancement in optical technologies, anometer level multiplexing can be implemented. Multiplexing of 8,16,32 or more wavelengths with smaller wavelength spacing is called DWDM.
As a result of broadband service providers moving from offering Connectivity to services, the discussion surrounding broadband entertainment has increased significantly. The Broadband Services Forum BSF) membership has identified a number of services that require significant focus in this decade; one of these is Internet Protocol Television (IPTV). This paper provides a high level, vendor&agnostic overview of what IPTV is and how it works. 
IPTV, essentially, has two components:
Part 1: Internet Protocol (IP): specifies the format of packets and the addressing scheme. Most networks combine IP with a higher&level protocol. Depending on the vendor solution, user atagram protocol (UDP) is the most typical higher level protocol. The protocol establishes a virtual connection between a destination and a source. IP allows you to address a package of information and drop it in the system, but there’s no direct link between you and the recipient.
Part 2: Television (TV): specifies the medium of communication that operates through the transmission of pictures and sounds. We all know TV, but here we are referring to the services hat are offered for the TV, like linear and on demand programming. Add the two components together (IP+TV) and you have: IPTV: specifies the medium of communication of pictures and ound that operates over an IP Network. Note: It is important to point out that IPTV services usually operate over a private IP network and not the public Internet. In a private IP network pecifically designed for IPTV, a service provider can ensure quality of service (QoS) for consumers. QoS refers to giving certain IP traffic a higher priority than other IP traffic. In an PTV network, TV signals are given the highest priority. As a result, the TV service is instantaneous; there is no downloading involved for the linear or on&demand content.
An IPTV service model offers a complete broadcaster and “cable programmer” channel line&up, including live programming delivered in real time. Additionally, it can offer a video on demand (VOD) ervice and enables the broadband service provider to develop new and unique services to differentiate their offering from competitors.
Download full seminar report on IPTV (IP Television)
Network security is a complicated subject, historically only tackled by well-trained and experienced experts. However, as more and more people become “wired”, an increasing number of people need to understand the basics of ecurity in a networked world. It explains the concepts needed to read through the hype in the marketplace and understand risks and how to deal with them.
Some history of networking is included, as well as an introduction to TCP/IP and internetworking. We go on to consider risk management, network threats, firewalls, and more special-purpose secure networking devices.
This is not intended to be a “frequently asked questions” reference, nor is it a “hands-on” document describing how to accomplish specific functionality. It is hoped that the reader will have a wider perspective on security in general, and better understand how to reduce and manage risk personally, at home, and in the workplace. The computer is the great invention of 20thcentury which has been now the part of our life. Gradually it became necessary to connect different computers that lead to establish local network. The network field grew up by eaps and bound that lead to huge matrix of computer network. This great invention is known as Internet. It benefited to human being in each & every field, which is now part of our life. But as we know each coin has two sides.
Similarly the darkness of network field is an unimaginable. For example whenever you connect to your internet, you provide “Gateway” to the hackers & crackers who are wiling to enter your machine thus whenever you connect to internet your machine is not secure at all.
Voice over IP is mainly concerned with the realization of telephone service over IP-based networks such as the Internet and Intranet. IP telephony is currently breaking through to become one of the most important service on the net. he actual breakthrough was made possible by the high bandwidth available in an intranet and, increasingly, on the internet. Another fundamental reason is the cost ssociated with the various implementations.
The public telephone network and the equipment makes it possible are taken for granted in most parts of the world. Availability of a telephone and access to low-cost, high quality worldwide network is considered to be essential in odern society (telephone are even expected to work when the power off).There is, however, a paradigm shift beginning to occur since more and more communication s in digital form and transported via packet networks such as IP, ATM cells, and Frame Relay frames. Since data traffic, there has been considerable interest in ransporting voice over data networks.
Support for voice communications using the Internet Protocol(IP), which is usually just called “Voice over IP” or VOIP, has become especially attractive given the low-cost, flat-rate pricing of the public Internet. In fact, toll quality elephony over IP has now become one of the key steps leading to the convergence of the voice, video, and data communications industries. The feasibility of carrying oice and signaling message over the internet has already been demonstrated but delivering high-quality commercial products, establishing public services, and onvincing users to buy into the vision are just beginning.
The use of light in communication is by no means a 20th century concept. In fact, in 1880, Alexander Graham Bell patented the photophone. However, it is the telephone that made him famous, not the photophone. ne reason why the photophone was not as successful as the telephone was that the technology to efficiently send light from one point to another did not xist at the time. Light from ordinary sources follows the inverse square rule. When the distance between a light source and an object is doubled, the intensity of the light shining on the object becomes one)fourth of what it as.
This is the reason why the technology to send light from one point to nother was very inefficient. Whereas light from other sources spreads out, light from a laser is xtremely directional. With the invention of the laser, the ability to efficiently send light from one point to another became a reality. The potential for transferring information using lasers was great. Here we resent a communications kit that demonstrates the basic concepts behind a modern telecommunications system.
Operational description of the Industrial Fiber Optics Laser Audio Transmission Project and RF Receiver Mainly, there are two parts in this telecommunications kit: the transmitter and the receiver. The transmitter has a RF input that is implemented with a tandard RCA jack. The receiver is connected to the television and has a RF output that uses standard RCA jack. The maximum analog voltage input that he laser can handle without distortion is 50 mill volts peak)to)peak.
The frequency range of the modulated signal has to be within the range of 100 Hz to 70 MHz. Due to a wide range of frequencies ) WBS laser can be used ith a wide variety of sources that transfer audio, video or audio/video signals. Examples of compatible signal sources include dynamic icrophones, video outputs from television or VCR’s (when used with an ttenuator), and modulated RF signals from VCR’s or external modulator boxes. When such sources are being used along with the WBS laser, one ust make sure that their output doesn’t exceed 50 mV peak to peaks.
Training is an important phase in a student’s life. During this period student gets both theoretical as well practical knowledge of the subject. Training also impresses a student overall approaches to the life 7 impress his personality & confidence.
Our training was in Doordarshan Kendra Ahmedabad. This report contains a detailed study of the Doordarshan Kendra Ahmedabad.
Doordarshan training report
There are three divisions here.
- 1. Studio.
- 2. Transmitter.
- 3. Earth station.
1. Studio:
The Doordarshan is a leading broadcasting service provider in India. The DD Ahmedabad has a full-fledged broadcast set up with three studios. Many serials & program are being made here like “EK DAL NA PANKHI”,”GAMMAT GULAL”,”KUNVARA CORPORATION” etc recorded in the studios.
So many outside programs are also been recorded using electronic units.
2. Transmission:
Here the transmission of both audio as well as video signals is being made. The transmission section does the function of modulation of signals, power amplification of the signal & mixing of the audio & video signals.
At last these signals are transmitted to antenna & we get the signal at almost 65 to 75 kms of the distance of the antenna.
3. Earth station:
The main function of the earth station is to make contact with the satellite or to communicate with it. The signals from other transmitters are down linked here. Also the signals here are also up linked to send it to larger distance.
Download DoorDarshan Training Report.
On October 1, 2000 the Department of Telecom Operations, Government of India became a corporation and was christened Bharat Sanchar Nigam Limited (BSNL). Today, BSNL is the largest Public Sector Undertaking of India and its responsibilities include improvement of the already impeccable quality of telecom services, expansion of telecom network introduction of new telecom services in all villages and instilling confidence among its customers.
At present the BSNL is the World’s Largest Seventh and India’s First Telecommunication Company.
Responsibilities that BSNL has managed to shoulder remarkably, definitely. BSNL is the largest telecom operator in India and is known to everybody for Basic Telephony Services for over 100 years. Presently the plain old, countrywide telephone service is being provided through 32,000 electronic exchanges, 326 Digital Trunk Automatic xchanges(TAX), Digitalized Public Switched Telephone Network (PSTN) all interlinked by over 2.4 lakhs km of Optical Fiber Cable, with a host of Phone Plus value additions to our valued Customers. BSNL’s telephony network expands throughout the vast expanses of the country reaching to the remotest part of the country.
Driven by the very best of telecom technology from chosen global leaders, it connects each inch of the nation to the infinite corners of the globe, to enable you to step into tomorrow.
Download BSNL Training Report here
Being able to send announcements to your employees is crucial to any company’s success. LAN Messenger allows company to inform their personnel about any important event or incidents in a matter of seconds.
LAN Messenger is compatible with Windows 95/98, Windows Me, Windows NT 4.0 as well as Windows 2000 and XP. It runs on any TCP/IP based Local Area Network (LAN). The LAN messenger is optimized for minimum network traffic and features and intuitive user interface allowing company employees to spend very little time learning this software.
LAN messenger main function is of intra-office communication. It can support number of users and no configuration is required and it easily works after installation. It does not require a server. It has the facility of automatic detecting users. It can send and receive instant messages efficiently. It also encrypts the data which is transferred for better security. It is compatible in all major versions of Windows. LAN messenger is an office popup which replaces WinPopup (Winpop) messenger which is also a LAN messenger that is supplied with Windows 9x/NT and unfortunately it does not work in Windows 2000 and XP.
Reliance infocom has built a national wide optic fiber based network infrastructure optic fiber was chosen as the preferred transport medium for reliance infocom, because of its undue advantages as compared to copper for carrying high data rates.
The network infrastructure spans 60,000 kilometers of optic fiber cable 250,000 kilometers of high-density polyethylene ducts and 30,000 kilometers of other cables.
The fiber to the building (FTTB) architecture is achieved through the access network. It enables end users to connect to the large telecommunication network. One of the most Interesting feature is the access node employed entitled digital loop carrier.
Reliance network has also introduced a new broadband technology employed in the copper access network entitled Digital subscriber loop.
The access network is functioning on the bases of protocol suite entitled V5 protocol.
Use of synchronous Digital Hierarchy (SDH) is within the city and Dense Wavelength Division Multiplexing (DWDM) for the national backbone ensures reliability, fast restoration from failures and low probability of outages. Use of several self-healing rings enables a high quality of service.
The Centralized Administrator of the entire Broadband Network through central Network Access center is one of the main features introduced in reliance architecture.
Download full reliance industrial training report here.
Tata Teleservices Ltd (TTSL) offers its products and services to customers across India under the name of “Tata Indicom”.
TATA Teleservices limited is India’s leading Private Basic Service Operator. TATA Teleservices is an integral part of the TATA Group’s holistic venture in the telecom industry. The Group has a significant presence in all sectors of the telecom industry – Basic, ISP, NLD and Broadband.
The company signed its license and inter-connects agreement with the Government of India on November 4 1997, when the Government opened up the Basic Services business to Private Operators.
TATA Teleservices brings the benefits of convergence to the customer’s doorstep. TTSL’s wire line connections are a mix of both copper and fiber, which enable clear voice transmission and faster data transmission. The Company is upgrading its wireless network to 3G 1X with capabilities of handling speeds up to 144 kbps and has a full-length managed network with centralized Network Management System. The network is highly reliable and supports monitoring and maintenance.
TTSL’s Pay Telephone Booths offer significant consumer benefits, including privacy & comfort. Operators and customers also benefit through accurate billing. TTSL has clearly demonstrated its leadership in Pay Telephony by setting up over 5000 Pay telephone booths in Andhra Pradesh. The Company has successfully replicated these value added services in the other five proposed circles of Delhi, Gujarat, Tamil Nadu, Karnataka & Maharashtra, thus effectively servicing its customer base of 13,17,000 customers across all the six circles it currently provides it services in.
download full tata tele services industrial training report here.
Communication Engineering, Seminar reports | Admin September 25, 2009 | 
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