STUDY ON BSNL TECHNOLOGIES
A Report submitted to GITAM INSTITUTE OF TECHNOLOGY, for the partial fulfillment of the requirements for the award of o f the degree
Of
BACHELOR OF TECHN OLOGY By Vavilapalli Divya Regd.No:1210408361
DEPARTMENT OF ELECTR O NICS AND COMMUNICATIO N ENGINEERING GITAM INSTITUTE OF TECHNOLOGY GITAM UNIV UNIVERSITY Rushikonda Rushikonda Vis Visak hapatnam-53004 1
DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING GITAM INSTITUTE OF TECHNOLOGY
GITAM UNIV UNIVERSITY VISAKHAPATNAM-530045 ISAKHAPATNAM -530045
CERTIFICATE
This is to certify that the Industrial Training Report entitled STUDY ON BSNL TECHNOLOGIES is a bonafide work done by Vavilapalli Divya bearing permanent Id
No.121040836 1 submitted submitted in partial fulfillment fulfillment of the requirements for the award of the degree Bachelor of Technology during a period from May 2011 to June 2011.
SIGNATURE OF INTERNAL GUIDE
SIGNATURE OF HEAD OF DEPARTMENT
Mrs.B.KANTHAMMA
Dr. V. MALLLESWARA RAO, M.E. PhD Dr
Assi Assistant Prof essor essor
Prof essor essor
Departm Departmeent of ECE of ECE
Departmeent of ECE Departm of ECE
2
DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING GITAM INSTITUTE OF TECHNOLOGY
GITAM UNIV UNIVERSITY VISAKHAPATNAM-530045 ISAKHAPATNAM -530045
CERTIFICATE
This is to certify that the Industrial Training Report entitled STUDY ON BSNL TECHNOLOGIES is a bonafide work done by Vavilapalli Divya bearing permanent Id
No.121040836 1 submitted submitted in partial fulfillment fulfillment of the requirements for the award of the degree Bachelor of Technology during a period from May 2011 to June 2011.
SIGNATURE OF INTERNAL GUIDE
SIGNATURE OF HEAD OF DEPARTMENT
Mrs.B.KANTHAMMA
Dr. V. MALLLESWARA RAO, M.E. PhD Dr
Assi Assistant Prof essor essor
Prof essor essor
Departm Departmeent of ECE of ECE
Departmeent of ECE Departm of ECE
2
ACKNOWLEDGEMENT
I express deep gratitude and sincere thanks to my guide Mrs.B.KANTHAMMA, Assistant professor, Department of Electronics and communication, for her timely guidance and constant support.
I thank PROF. D. PRASADA RAO, PhD, Principal and Dean, who gave us this opportunity to get a pr actical view of subject through this Industrial Training.
I express my deep gratitude to DR.V.MALLESWARA RAO, Head of the Department, ECE, for his constant support and encouragement.
I thank Mr. K. CHANDRA SEKHAR (D.E, OCB&BB, BSNL) for giving me an opportunity to learn at their premises and I express my deep gratitude to the industry guide Mr. V. RAMESH NAIDU (J.T.O), the co-operative management and helpful staff for giving me knowledge of their services and helping me from time to time.
I take the privilege to thank all the people who either directly or indirectly helped me in making this training a success.
V.Divya (Regd.No. 1210408361)
3
CONTENTS 1) BSNL Overview a) Infrastructure b) Interesting Facts c) BSNL Services d) BSNL IT Tool 2) Making A Telephone Call 3) The Exchange a) Computer Unit b) Power Plant c) AC Plant (Central Air Conditioner) d) Introduction To OCB-283 e) Main Divisions Of OCB 4) Internet a) Internet Technologies b) OSI Networking Model c) Common Common Terminology Used In Internet d) National Internet backbone (NIB) 5) Broadband a) Introduction to Broadband b) Technological O ptions c) Broadband Connection At Home 6) Wi-Fi 7) WiMAX 8) Cellular Mobile Services a) WLL (Wireless In Local Loo p) Mobile b) Code Division Multiple Access (CDMA) Mobile Mo bile c) Global System For Mobile Communication (GSM) d) Third Generation (3G) Technology 9) BSNL¶s IP TV 10) Conclusion
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1. BHARAT SANCHAR NIGAM LIMITED (BSNL) OVER VIEW
Bharat Sanchar Nigam Limited (abbreviated BSNL) is a stateowned telecommunications company headquartered in New Delhi, India. BSNL is one of the largest Indian cellular service providers, with over 87.1 million subscribers as of April 2011, and the largest land line telephone provider in India. However, in recent years the company's revenue and market share plunged into heavy losses due to intense competition in Indian telecommunications
sector.
BSNL is India's oldest and largest communication service p rovider (CSP). It had a customer base of 90 million as of June 2008.It has footprints throughout India except for the metropolitan cities of Mumbai and New Delhi, which are managed by Mahanagar Telephone Nigam Limited (MTNL). As of June 30, 2010, BSNL had a customer base of 27.45 million wire line and 72.69 million wireless subscribers.
st
It is India¶s largest telecommunication company with 24% market share as o n March 31 2008.its headquarters are at Bharat Sanchar Bhawan, Harish Chandra Mathur Lane, New Delhi. It has the status of MINI RATNA, a status assigned to public sector companies in India.
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External/internal
infrastructure:
y
y
Interesting
External infrastructu re : Lines and cables(U/G including OFC ) Internal infrastructure : Battery, Power Plant, E/A, A/C plant, MDF, Switches ( C-DOT, OCB 283, EWSD, AXE etc ), Leased Lines ( MLLN ), Broad Band, MPLS VPN.
Facts:
There are 2 million BSNL mobile connections in rural
India (a record, no other connection is as famous as bsnl
in rural areas)
BSNL supplies phone lines to all other network such as Airtel, Vodafone etc.
Largest pan India coverage-over 11000 towns & 3 lakh Villages.
India¶s No. 1 wireless service provider with more than 50 Million customers.
An incredible speed of 2mbps is only offered by BSNL
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BSNL
Services:
1) BSNL LANDLINE
NEW TELEPHO NE CO NNECTIO N
y
y
PERMANENT CO NNECTIO N
y
CO NCESSIO N IN RENTALS
y
SHIFT OF TELEPHO NE
y
TRANSFER OF TELEPHO NE
y
TELEPHO NE TARIFF
2) BSNL MOBILE
y
POSTPAID
y
PREPAID
y
UNIFIED MESSAGING
y
GPRS/WAP/MMS
y
DEMOs
y
TARIFF
y
SMS & BULK SMS
3) BSNL WLL 4) INTERNET SER VICES y
NETWORK
y
BR OADBAND
y
TYPES OF ACCESS
y
INTERBET TARIFF
y
DIAL-UP INTRENET
y
Wi-Fi
7
5) BSNL BROADBAND
y
REGISTER O NLINE
y
TARIFF
y
CHECK USAGE
y
FAQ
6) ISDN
7)
y
ISDN
y
TARIFF
VIDEO CONFERRENCING
y
OVERVIEW
y
TARIFF
y
FAQ
8) AUDIO CONFERRENCING
9)
y
OVERVIEW
y
TARIFF
y
FAQ
TELEX/TELEGRAPH
y
TELEX/TELEGRAGH
y
TARIFF
10) INET y
OVERVIEW
y
SERVICES O N I NET
y
USING O N I N
8
11) EPABX
BSNL
y
EPABX
y
CENTREX
y
TRANSPO NDER
y
RABMN
IT tool
BSNL Working Environment
IT Tool used in BSN
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DOTSOFT:
Dot Soft is the first integrated telecom software application in BSNL comprising of commercial, billing, accounting, fault repair service and d irectory enquiry services. It has been conceptualized, designed and developed entirely by the core group of the Software Development Centre of the O/o CGMT, AndhraPradesh Telecommunications Circle, Hyderabad. It is based on the latest software technologies running on a WAN and is the first of its kind in BSNL in the field of information technology. First
it was tested and implemented in Guntur SSA in 1997.
It has been successfully implemented in 171 SSAs across the country. All the SSAs of Andhra Pradesh, Tamilnadu, Karnataka, Assam, Punjab, C hhattisgarh and Gujarat Telecom circles. Rest of SSAs is from states o f Maharashtra, Madhya Pradesh, Uttar Pradesh, Rajasthan, J&K a nd Haryana. It has been approved by the Telecom Commission for implementation all over India. Dot soft ensures better customer satisfaction and transparency in BSNL service. Dot Soft is an enterprise wide telecom database system that revolutionizes the operation and supervision of customer services by enabling all the personnel to work online. The central server contains the complete database to which all the nodes anywhere in the district log in. The database is accessed using application software residing in the nodes which have GUI interface.
OS:
Linux Front end: Forms 6i Back end Database: Oracle 9i Client Server Model ± 2 layer architecture
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DOTSOFT
- Network Elements
11
R outer
A Layer 3 (Network Layer of OSI Model) device
Enables transit of packets between two LAN's.
Traffic can be monitored, administered from the Ro uter.
Switch
A Layer 2 (Data Link Layer of OSI Model) device.
Enables transit of packets within a LAN.
Flow
of frames is done in the
Hub
A Layer 1 (Physical Layer of OSI Model) device
Enables transit of packets within a LAN.
The signal amplification is done.
control / Error Detection / Signal amplification switch.
The data from the data link layer is converted into electrical signals and sends on physical media.
Modem
For
The nodes in the customer service centre service all the subscriber requests which flow to the commercial and accounts sections as the case may be.
After validation and approval from the co ncerned sections the work orders flow to the different field units depending on the activity.
After the completion of the work orders the commercial and billing data of the subscriber gets updated.
conversion of different protocols. (PPP protocol).
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For
example Ethernet to Serial Interface
2. MAKING A TELEPHONE CALL A telephone call starts when the caller lifts the handset of the base. Once the dial tone is heard, the caller uses a rotary or a push button dial mounted either on the handset or on the base to enter a sequence of digits, the telephone number of called party. The keys control a tone generator circuit that makes DTMF tones that the exchange rece ives. A rotary-dial telephone uses pulse dialing, sending electrical pulses, that the exchange can count to get the telephone number. The exchange determines whether the ca lled party is in the same exchange o r different ones. If the called is in the same exchange, burst of ringing current is applied to the ca lled party¶s line. Each telephone contains a ringer that responds to specific electric frequency. When the called party answers the telephone by picking up the handset, steady current starts to flow in the ca lled party¶s line and is detected by the exchange. The exchange then stops applying ringing and sets up the connection between the caller and the called party. If the called party is in different exchange from the caller, the caller exchange sets up the connection over the telephone network to the called party¶s exchange. The called party then handles the process of ringing, detecting an answer, and notifying the calling and billing machinery when the call is completed. When conversation is over, one or both parties hang up by replacing their handset on the base, stopping the flow of current. The exchange then initiates the process of taking down the connection, including notifying billing equipment of the duration of the call if appropriate.
3. THE EXCHANGE All telephone subscribers are served by auto matic exchanges, which perform the functions the human operator. The number being dialed is stored and then passed to the exchange¶s central computer, which in turns operates the switching to complete the call or routes it a higher level switch for further processing. Today¶s automatic exchanges uses a pair of computers, one running the program that provides services and the second monitoring the o peration of the first, ready to take over in a few seconds in the event of equipment failure. Various exchanges present in BSNL are: E-10B OCB283 EWSD All exchange has some purposes and some basic structural units, which are: 1. subscribers connection unit 2. Switching network (CX) 3. Control unit 4. OMC
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For
smooth working of an exchange following unit are very important:-
1. Computer Unit: - it deals with additional services o f the exchange to the customers with the help of computers. 2. Power Plant: - to feed proper power supply to exchange 3. AC Plant: - to maintain the continuous temperature + or ± 2 degree Celsius to the digital switch (exchange). 4. MDF: - to connect switch (exchange) with the external environment (subscriber) i.e. it is the interface between subscribers and exchange.
1) Computer unit As the name specified it is the main part of the exchange that deals with the all services provided by the exchange to the customers with the help of computer. It also provides the updated data to all other part of the exchange. The customers are using the services of the exchange by using the internet also gets connected to the main server present this room via an internet room. It mainly consists of the servers that are pro viding the different services. The main servers of this room are:IVRS is used for the change number services provided by the exchange. CERS are provided by the exchange to avoid the problems that the users are facing the repa iring of telephone. In this system when the user enters his complain it gets directly entered to the server and user is allotted with an id number. LOCAL DIRECTOR Y ENQUIR Y is another services provided by the exchange, by using this; subscribers calls the particular number and gets the directory enquiry. The server present in the main computer room provides this service. INTERNET DIRECTOR Y ENQUIR Y is the latest service by the exchange. In this type of service makes it enquiry using the internet, which gets connected to the main server at the internet room in the exchange a nd further to the main server in the computer room.
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2) POWER PLANT
As we know that, the po wer is the main source or any organization. It is the case of E-10B exchange. That is the first requirement of any organization is the input. The main source of this exchange is AC supply. However, as soon as the power supply is gone off, then what is the source? No one think on this that the telephone is always plays its ro le in the human life. Even if the power supply gone off. Thus there must be adjustment source of power. The main parts of the po wer room are: Batteries: - these are the instant sources of the power as soon as power is gone off. UPS (Uninterrupted Power Supply):- the UPS must give supply to the computer. As we know there is some equipment which can withstand any type of power supply, but there are also some instruments which cannot withstand with this type o f power supply, even a microsecond delay will cause the loss of data. Charging- Discharging Unit: - the batteries we are using in the p ower room need timely charging. As soon as the AC power supply is on, we make use of the charging unit present in the power room. The slowly charging of the batteries is known as the trickle charging. But sometimes we need the BOOSTER charging. In this type of charging awe take of the batteries from the load and charge separately, until it gets fully charged. The main work of the discharging unit is to control the discharging of the batteries. Inverter and Converter Unit: - the main use of this system is to change AC mains to DC and vice versa as required by the parts of exchange. Engine Room:-we know that the batteries are the instant source of supply but we cannot use it for much larger time, thus for this, we have an engine to generate the power supply. They are of 885 KVA. Thus, this room controls the supply of the engine.
3) AC PLANT For
the function of electrical equipment, cooling system is basic requirement.
The basic advantages of cooling systems are following: >It provides the thermal stability so that the temperature does not reach the tolerance limit of electronic equipment. >It saves equipment from dust so to avoid malfunction of equipment. >It protects equipment from excess humidity which can caused rust ing of equipment. 15
The basic unit of measurement used in the industry is known as ³ton o f refrigeration´ (TR) which is equivalent to the heat extracted in 24 hours for converting thousands kg of liquid to ice at zero degree. The compressor is the heart of the AC system and the costliest. It increases the pressure and temperature of the refrigerant gas coming from the evaporator coils by compressing it. Compressor comes in various types. The most widely used is simple reciprocal type a cylinder and piston arrangement. For capacity more than 120 TR, centrifugal compressors are used. The condenser liquefies the refrigerant gas by a heat exchange process. The capillary tube or the expansion valve pressurizes liquid refrigerant and meters it flows to the evaporator. The refrigerant then passes through the evaporato r coils, which extract heat out of the a mbience.
OCB-283(Organde
Control Version B)
OCB-283 is digital switching system, which supports a variety of communication needs like basic telephony, ISDN, interface to mobile, data communication. ALCATEL of France has developed this system.
The first OCB-283 exchange of R11 version were commissioned in Brest (France) and Beijing (China) in 1991, first OCB-283 exchange came to India in 1993. The system has been upgraded and current version R20 has fully validated in Jan 1994. The latest version is R24. All new technology switching system, are based o n (SPC) stored program control concept. The call processing program is distributed over different control organs of the system and is stored in R OM/RAM of the units. Data required to handle the calls are also managed in RAM of different control units.
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Salient Features of the System 1. It is a digital switching with single µT¶ stage switch. A maximum of 2048 PCM¶s can be connected. 2. It supports both analog and digital subscribers. 3. It supports all the existing signaling systems, like decadic, MF (R2), CAS and also CCITT#7 signaling system. 4. It provides telephony, ISDN, Data communication, cellular radio, and other value added services. 5. The system has µautomatic¶ recovery feature. When a serious fault occurs in a control unit, it gives a message to SMM. The SMM puts this unit out of service, loads the software of this unit in a back up unit and brings it into service. Diagnostic programmers are run on the faulty unit and the diagnostics is printed on a terminal. 6. It has a double remoting facility. Subscribers¶ access unit can be placed at a remote place and connected to the main exchange through PCM links. Further, line concentrators can also be placed at a remote location and connected to the CSNL or CSND through PCMs. 7. Various units of OCB 283 system are connected over token rings. This enables fast exchange of information and avoids complicated links and wiring between various units. 8. The charge accounts of subscribers are automatically saved in the disc, once in a day. This avoids loss of revenue in case o f battery failure. 9. The traffic handling capacity of the system is huge. 10. The exchange can be managed either locally or from an NMC through 64 kb/s link. 11. All the control units are implemented on the same type of hardware. Th is is called a station. 12. The system is made up of only 35 types of cards. This excludes the cards required for CSN. Due to this, the number of spare cards to be kept for maintenance is drastically reduced. 13. The system has modular structure. The expansion can be very easily carried out by adding necessary hardware and software. 14. The SMMs are duplicated with one active other standby. In case of faults, switch over takes place automatically
17
15. The hard disc is very small in size, compact and maintenance free. It has a very huge memory capacity of 1.2 Giga bytes 16. The space requirement is very small. 17. There is no fixed or rigid rack and suite configuration in the system.
Main
y y y
Divisions Of OCB-283
MDF Room. Exploitation Room. Switching Room.
MDF (Main Distribution Frame), this room is used to distribute the subscriber¶s call according to his request.
In any type of exchange, there is a unit called main distribution frame and is used for interconnection of exchange line and junction unit equipments to external physical lines coming to the exchange. The distribution frame provides easy and flexible interconnect ion, isolation point for testing, protective devices used for safety of exchange equipment etc. In MDF, all lines are coming from subscribers, non exchange lines, telex lines and a nalog junction lines, are terminated on 100 pair krone type tag blocks in which gas discharge tubes type protective devices are provided to tackle voltages and current surges. These tag blocks are located on one side of the MDF called ³line side´. On the other side of the MDF called ³exchange side´ tag blocks re provided for terminating the cables from CSE for subscriber lines and from transmission room for analog junction lines.
TRANSMISSIO N MEDIA
In many communication systems, it is often necessary to interconnect points that are some distances apart from each other. The transmission of information as an electromagnetic signal always occurs as a transverse electromagnetic wave. One of the media for transmission is:
18
Coaxial cable:
Optical Fiber Cable:
In the Switching R oom all the information is stored in the ZD-Racks. The Exploitation R oom operates the whole OCB-283 exchange. So it is also known as operational room. My main responsibilities are come under this exploitation room. As in this 19
room all the operations are done through system software by operating different commands over there. I have to operate some of these commands, which are named as under and discussed in detail with the help of example as under: y y
IDABSE INDIN
4. INTERNET The Internet is a group o f various co-operating computers worldwide interconnected by computer based on TCP\IP communication protocols. People use it to get information over a standard communication link. The hundreds o r thousands or millions of computer network are connected to each other for exchanging the information which is based on the unique identity and set of procedures. Internet is a series of interconnected networks providing global link to information. GIAS:
BSNL launched the Gateway Internet Access Service (GIAS) through dial up/leased/ISDN network. Users can access GIAS from 99 cities in India by this means.
INTERNET TECHNOLOGY The basic function of Internet can be summarized as under>Interconnecting of computers to form a netwo rk. >Interconnecting of computers to form a netwo rk of networks. >To establish a communication link between two computers within as network. >To provide alternate communication link among the networks, even if one network is not working. These are based on TCP/IP communications protocol. Transf er of a file through Internet
Suppose a file is to be transmitted on Internet from one computer to ot her ones, >Break the file in to small packets >Attach destination and source address in to packets >Multiplex and transmit these packets >At destination de-multiplex the packets >Remove address bits from the packets and assemble the data in to t he original file >Make source bits as destination address and send t he acknowledgement in to the source Therefore, it is clear that network hardware sends the packets to specified destination and network software reassembles of communications, the computer network performs the following functions20
Addressing and routing Fragmentation and error correction Data error checking Connectivity control Multiplexing and de-multiplexing Data flow control End users interface etc. The data handling
A single module cannot handle the entire process. One that adopted as a standard is an open system interconnection (OSI) model.
OSI NETWORKING MODEL The O pen Systems Interconnection (OSI) model defines all the methods and protocols needed to connect one computer to any other over a network. The OSI model separates the methods and protocols needed for a network connection in to seven different layers. Each higher layer relies on services pro vided by a lower level layer. The OSI model is sometimes called ³the seven layer model´. It was developed by the International Standards Organization (ISO) in 1983 and is documented as standard 7498.
Layers are:
Application layer Presentation layer Session layer Transport layer Network layer Data link layer Physical layer
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PHYSICAL LAYER: The physical layer defines the properties of the physical medium used to make a network connection. It includes a network cable that can transmit a stream of bits between nodes on the physical network. The physical connection can be either point to point or multipoint, and it can consist of either half duplex (one direction at a time) or full duplex (both directions simultaneously) transmissions. Moreover, the bits can be transmitted either in series or in parallel (most network use a serial stream of bits, but t he standard allows for both serial and parallel transmission). The specification for the physical layer also defines the cable us ed, the voltages carried on the cable, the timing of the electrical signals, the distance that can be run, and so on. For example, a NIC network interface network) is part of the physical layer. DATA LINK LAYER: The data link layer, layer 2, defines standard that assign meaning to the bits carried by the physical layer. It establishes a reliable protocol through the physical layer, so the network layer (layer 3) can t ransmit its data. The data link layer typically includes error detection and correction to ensure a reliable data stream. The data elements carried by the data link layer are called frames. Examples of frame types include x.25 and 802.x (802.x includes both Ethernet and Token Ring networks).
The data link layer is usually subdivided in to two sub layers, called the Logical link control (LLC) and Media Access Control (MAC) sub layers. The LLC sub layer performs tasks such as call set up and termination and data transfer. The MAC sub layer handles frame assembly a nd disassembly, error detection and correction, and ad dressing. The two most common MAC protocols are 802.3 Ethernet and 802.5 Token ring .Other MAC protocols include 802.12 100 Base VBG, 802.11 Wireless, and 802.7 Broadband. Network Layer: The network layer, Layer-3, is where a lot of action goes on for most networks. The network layer defines how data packets get from one point to another on network. The Network layer is also known as packet layer, it defines different packet protocols, such as Internet Protocol (IP) and Internet Protocol Exchange (IPX). These packet protocols include source and destination routing information. The rout ing information in each packet tells the network where to send the packet s to reach its destination and tells the receiving co mputer from where the packet originated. Transport Layer: The Transport Layer, layer-4, manages the flow of information from one network node to another. It identifies each computer or node on a network uniquely. It ensures that the packets are decoded in the proper sequence and that all packets are received. Transport layer protocols include Transmission Control Protocol (TCP) and Sequenced P acket Exchange (SPX).Each is used in concert with IP and IPX respectively. Session layer: The session layer, layer-5, defines the connection from a user to a network server, or from a peer on a network to another peer. These virtual connections are referred to as sessions. They include negotiation between the client and the host, or peer and peer, on matters of flow and control, transaction- processing, transfer of user information, and authentication to t he network.
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Presentation Layer: The presentation layer, layer-6, takes the data supplied by the lower level layer and transform so it can be presented to the system. The Presentation layer can include data compression and decompression as well as dat a encryption and decryption. Application Layer: The Application layer, layer 7, controls how the operating system and its application interact with network. As mentioned ear lier, data flows from an application program or the operating system, and then goes through the protocols and devices that make up the seven layers of the OSI model one by one until the data arrives at the physical layer and is transmitted over the network connection. The computer at the receiving end reverses this process. At each stage of the OSI model, the data is ³wrapped´ with new control information related to the work done at the particular layer. This control information is different for each layer, but it includes headers, trailers pre-ambles, and po st-ambles. Therefore, for example, when the data goes into the networking software and components making up the OSI model, it starts at the application layer and includes an application header and application data. Next, at the presentation layer, a presentation header is wrapped around the data and it is passed to the session layer, where a session header is wrapped arou nd all the data, and so on, until it reaches the physical layer. At the receiving computer this process is reversed.
COMMON TERMINOLOGY USED IN INTERNET WWW:
World Wide Web (WWW) is a wide area hypermedia information retrieval aiming to give universal access to a large universe o f documents. HTTP:
Hyper text transmission Protocol (HTTP) is the communication protocol used to transfer documents from the server to client over the WWW (http:// www). HTML:
Hyper Text Markup Language (HTML) is a system of marking or tagging the various part s of web documents to tell the browser software how to display the document text, link graphics and link media. ISDN:
Integrated Service Digital Network (ISDN) is a digital phone co nnection technology that provides both voice and data services over the same connection. ISP:
Internet Service Provider (ISP) is an agency t hat provides Internet access and other net related services.
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National Internet Back bone (NIB) The Internet back bone refers to the principal data routes between large, strategically interconnected networks and core routers in the Internet. These data routes are hosted by commercial, government, academic and other highcapacity network centers, the Internet exchange points and network that interchange Internet traffic between the countries, continents and across the oceans of the world.
Architectural
Principles
The Internet, and consequently its backbone networks, do not rely on central control or coordinating facilities, nor do they implement any global network policies. The resilience of the Internet results from its principal architectural features, most notably the idea of placing as few network state and control functions as possible in the net work elements, but instead relying on the endpoints of communication to handle most of the processing to ensure data integrity, reliability, and authentication. In addition, the high degree of redundancy of today's network links and sophisticated real-time routing protocols provide a lternate paths of communications for load balancing and congestion avoidance.
NIB
in India
India's backbone is very extensive due to a very large population. This country alone has nearly 250 million internet users as of 2009. Four of India's top Internet Service Providers are Tata Communications, BSNL, MTNL, and Reliance Communications. Tata Communications is a Tier-1 IP network, with connectivity to more than 200 countries across 400 Pops and nearly 1,000,000 square feet (93,000 m2) of data center and collocation space worldwide. It is India's largest provider in data center services and a lso operates India's largest data center in Pune. The backbone structure keeps on getting stronger because of the huge number of new emerging mobile operators which leads to decrease in pr ices due to competition in the market.
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5. BROADBAND INTRODUCTION Rapid growth of data communication market and popularity of Internet, reflect the needs of enhanced infrastructure to optimize the demand of traffic. Integration of telecom and computer networking technology trend has further amplified the importance of telecommunications in the field of information communication. It becomes a too l for the conveyance of information, and thus can be critical to the development process. As the Internet market co ntinues to explode, demand for greater bandwidth and faster connection speeds have led to several technological approaches developed to provide broadband access to all consumers. A concept of broadband services and t he means of access technologies to bridge the customer and service provider is emerged out throughout the world. ³Broadband´ refers to highspeed Internet access. Broadband solutions represent the convergence of multiple independent networks including voice, video and data into single unified broadband network. DEFINITIO N: Broadband is the nonspecific term for high-speed digital Internet access. To state the obvious, µbroadband¶ indicates a means of connectivity at a high or µbroad¶ bandwidth. There are the various ways to define the broadband:Term for evolving digital technologies that provide customers a high-speed data network connection. Provides signal switched facility offering integrated access to voice, dat a, and video and interactive delivery services. The Federal Communications Commission (FCC) defines Broadband as an advances telecommunication capability. Delivers services & facilities with an upstream and downstream speed 200 Kbps or more. Range varies from 128 Kbps to 100 Mbps. y
y
y
y
In fact there is no specific International Definition for Broadband.
Professional Activities: Telecommuting (access to corporate networks and s ystem to support working at home on a regular basis). Video conferencing (one to o ne or multiple person video telephone calls). Home based business (e-commerce). Home office. y
y y y
Entertainment Activities: Web surfing. Video on demand. Video games. y y y
25
Consumer Activities: Shopping. Telemedicine (remote doctor¶s remote medical analysis). Distance learning. Public services. Information gathering. Photography. y y y y y y
TECHNOLOGY OPTIONS FOR BROADBAND SER VICES Communication of data with different throughput is feasible by following t echnologies: Narrow Band 2.4Kbps ± 128Kbps. Broadband 256Kbps ± 8000Kbps. LAN 1000 ± 100Mbps. y
y
y
Broadband communication technology can be divided broadly in two categories:Wire line Technology. Wireless Technology. y y
WIRE LINE TECHNOLOGIES INCLUDE 1. Digital Subscriber Lines (DSL) on copper loop. 2. O ptical Fibre Technologies. 3. Cable TV Networks. 4. PLC (power line communication).
WIRELESS TECHNOLOGIES INCLUDE 1. Satellite Media 2. Terrestrial Wireless 3. 3G Mobile 4. Wi-Fi (wireless Fidelity) 5. Wi-Max. 6. FSO (free space optics).
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BROADBAND CONNECTION AT HOME For
Broad band connection at Home or office 5 things are required 1. Telephone Connection. 2. Modem. 3. Splitter. 4. LAN Card. 5. Ethernet cord.
Steps for Broadband connection are as follows:1) A form for broadband connection is filled at BSNL office mentioning the plans preferred. Office after verifying the form and submission of fees provide username and password to the user. 2) Office also provide modem or user can buy his own modem from market. 3) There are two types of modem available in the market Type 1 modem ±without Wi-Fi facility Cost-1200-1300Rs Type 2 modem ±with Wi-Fi facility Cost-1800-2000Rs 4) Officer at BSNL department enters the serial number of modem in h is CRM and activates the broad band connection for requested number. 5) Now main telephone cord is connected with splitter. Splitter has 3ports In one port main telephone line is attached. In second port o utgoing for telephone instrument is attached. Third one is for modem. 5)
nd
Ethernet cord attaches modem and computer. Modem as 3 LED lights on it 1 is for DSL 2 one is for power & 3rd for line when line is clear and no disturbance is there line LED is stable. When Broadband connection is activated by CRM DSL also become stable.
6) Now modem installing is done in computer for this open the network window on our operating system. 7) Enable the Local Area connection option on yours window. 8) Enter the IP address provided by BSNL in the address bar of internet explorer. A home page of BSNL is opened enter your username and password given by BSNL office. 9) Select bridging or PPPOE mode and do next. 10) As the username and password is verified ok buttons appears click it. Now o n modem setting or programming is finished.
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11) Now on Network and sharing centre window set up a new connection. Click on ³connect to internet ³option and click next now select type of connection (broadband pppoe) and then fill the username and password. Then click ³connect´. 12) Internet session is started indicating the speed. 13) Now you can surf various websites by your browsers.
6. Wi-Fi What is Wi-Fi?
Short for wi reless f i delity
Wi-Fi is a wireless technology that uses radio frequency to transmit data through the air.
What can you do with it?
Quick/easy temporary network access
Staff access to corporate network
Patron internet access (hotspot)
Interconnecting two networks
Advantages
Setup Cost ± Reduced cabling required
Flexibility
± Quick and easy to setup in Temporary or permanent space
Scalable ± Can be expanded with growth
Freedom
± You can work from any location That you can get a signal
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Lower total cost of ownership ± Because of Affordability and low install cost Additionally, Mobile Users ± Can access the Corporate Network from any public hotspot using VPN
Disadvantages planning
± Depending on the goal
Security ± Greater exposure to risks Access Compromising Data Denial of Service Speed ± Slower than cable
Range ± Affected by various medium Travels best through open space Reduced by walls, glass, water, etc
7. WiMAX WiMAX stands for Worldwide Interoperability for Microwave Access. It is a telecommunications technology providing wireless data over long distances in a variety of ways, from point-to-point links to full mobile cellular type access. It is based o n the Wireless MAN (IEEE 802.16) standard.
WiMAX is a highly scalable, long-range system, co vering many kilometers using licensed spectrum to deliver a point-to-point connection to the Internet from an ISP to an end user. WiMAX can be used to provide a wireless alternative to cable and DSL for broadband access, and to provide high-speed data and telecommunications services. WiMAX can also be used to connect many Wi-Fi hotspots with each other and also to other parts of the Internet. When using WiMAX device with directional antennas, speeds of 10 Mbit/s at 10 km distance is possible, while for WiMAX devices with omni-directional antennas only 10 Mbit/s over 2 km is possible. There is no uniform global licensed spectru m for WiMAX, although three licensed spectrum profiles are being used generally ± 2.3 GHz, 2.5 GHz and 3.5 GHz .
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With WiMAX enabled handsets and laptops coming into the market, people could connect to the fast broadband internet from anywhere, without having to depend on the slow rate mobile network data transfer. You can work on broadband, call friends and colleagues and watch realtime TV from the top of a forest hill station many kilometers away from the access point ± without compromising on quality, speed or screen size! WiMAX could connect remote Indian villages to the Internet using broadband. This wou ld avoid hassles in cabling through the forests and ot her difficult terrain only to reach a few peop le in remote places. Maintaining such system would also be easy. WiMAX could provide Internet access, voice and IPTV to those areas.
Advantages 1) Single station can serve hundreds of users. 2) Much faster deployment of new users comparing to wired networks.
3) Speed of 10 Mbps at 10 kilometers within line-of-site. 4) It is standardized, and the same frequency equ ipment should work together.
Disadvantages 1) Line of sight is needed for more distant connections. 2) Bad weather conditions such as rain could interrupt the signal.
3) Other wireless equipment could cause interference. 4) Multiplied frequencies are used. 5) WiMAX is a very power-consuming technology and requ ires significant electrical support. 6) High installation and operational cost.
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Wimax Applications Wimax network provides the ability for service pro vider to deploy new era broadband service. Wimax applications are most effective than today. It provides a broad customer base, while adding up a mobility feature to those services. Wimax technology applications are a mean of service providers to present data, video, voice, mobile and internet access. There are various benefits of Wimax technology such as it provides simple based prospective cost saving and service efficiency but to be capable t o allow VoIP calling, mobile devices, video making and high speed data transfer.
8. CELLULAR MOBILE SER VICES Cellular is one of the fastest growing and most demanding telecommunication applications. Today, it represents a continuously increasing percentage of all new telephone subscriptions around the world. Currently there are more than 45 million subscribers in worldwide and nearly 50% of those subscribers are located in USA. It is forecasted that cellular system using a digital technology will become the universal method of telecommunications. By the year 2005, forecasters predict that there will be more than 100 million cellular subscribers worldwide.
1. WIRELESS IN LOCAL LOOP (WLL) MOBILE WLL is a communication system that connects customers to the Public Switch Telephone Network (PSTN) using radio frequency signals as substitutes of conventional wires for all part of connection between the subscribers and the telephone exchange. It works on CDMA technique. The local loop is access part of telecommunication network i.e. the part between PSTN switch and subscribers. WLL network application involves uses of radio to replace of the wire link between PSTN switch and subscriber. The radio technology is able to provide same quality of services as that provided by the wires line. Application of wireless loop technology has just been started in the worldwide. There is no standard for this so far. However, a number of national and international air interface standards for digital cellular mobile telephone system are available.
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TECHNICAL ASPECTS:
WLL is based on CDMA technique and is entirely different from
GSM.
The system for
WLL services can be divided into following parts: BSC (Base Switching Centre):- It provides links between BTS & BSM; it consists of different
processors, in BSNL it is of SUN Polaris of L G Company. In BSNL we have two types of BSC:-
I.
V-5.2:- This type of BSC cannot switch by itself so it is dependent on local exchange /
PSTN for switching and keeping records of billing etc. BSNL uses this type of BSC for rural areas.
II.
CCS-7 / R2:- These types of BSC are totally automatic it doesn¶t depend on local
exchange for its functions, it is complete in itself. BSNL uses this type of BSC for urban areas.
BTS (Base Transceiver System):- As it is clear from its name it transmits as well as receive signal, it works as an amplifier (router) to overcome the loss in signal in transmission.
BSM (Base Station Management):- It controls and manages the WLL services. It can
troubleshoot the problem; add new users as we ll as capable to block service given to user. It is basically a computer system, which manages t he whole process of WLL service. In BSNL BSM are two UNIX based computer system.
ADVANTAGES OF WLL:
1- Cost of installation and Maintenance of WLL is lower than cable network 2- Installation time is less. 3- Selective installation for those who require connection at certain time. 4- Quality of wireless technology has improved the speech qu ality 5- Cellular systems are too expensive with lesser signal quality than fixed bro ad band wireless that use directional antennas
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2. CODE DIVISION MULTIPLE ACCESS (CDMA): CONCEPT OF MULTIPLE ACCESSES
Multiple access system allows a large number of users to share a common pool of radio telephone circuits, like sharing of trunked radio facility. Multiple access radio has similarity to the LAN in which the co mmon channel is available to all users. The c ircuits are demands assigned i.e. assigned on demand first-cum-first-served basis. CDMA: - Where large number of transmission are combined on the same channel at the same time and separated by the codes.
WHAT IS CDMA?
CDMA, a cellular technology originally known as IS-95, competes with GSM technology for dominance in the cellular world. There are now different variations, but the original CDMA is known as CdmaOne. CDMA uses wide-band spread spectrum techniques for signal transmission, as opposed to narrow-band channel techniques used in conventional analog systems. CDMA channels the packets o f voice and data over wireless radio frequencies so a cellular user can hear better, quicker and with more quality than ever before. CDMA cell phones are also more efficient as they use a channels "band-with" efficiently.
3. GLOBAL SYSTEM FOR MOBILE COMMUNICATION (GSM) What is GSM? GSM
is a standard for a Global System for Mobile communications. Global System for Mobile communications, a mobile phone system based on multiple radio cells (cellular mobile phone network). It has been agreed upon and is completed by ETSI, the European Telecommunications Standards Institute. The Goals of GSM:
a) Improved spectrum efficiency b) International roaming
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c)
Low-cost mobile sets and base stations
d)
High-quality speech
e)
Support for new services
GSM Services:
a) Tele-services b) Bearer-Data Services c) Supplementary services Tele-services:
Telecommunication services that enable voice co mmunication via mobile phones.
Offered services
a) Mobile telephony b) Emergency calling Bearer-Data Services:
Include various data services for information transfer between GSM and other networks like PSTN, ISDN etc at rates from 300 to 9600 bps.
Short Message Services up to 160 character alphanumeric data transmission to/from the mobile terminal a) Unified Messaging Services (UMS) b)
Group
3 fax
c) Voice mailbox d) Electronic mail
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Supplementary services: Call related services-
a) Call Waiting- Notification of an incoming call while on the handset b) Call Hold- Put a caller on hold to t ake another call c) Call barring- All calls, outgoing calls, or incoming calls d) Call Forwarding- Calls can be sent to various numbers defined by user e) Multi Party Call Conferencing - Link multiple calls together
GSM System Architecture:
Mobile Station (MS)
a) Mobile Equipment (ME) b) Subscriber Identity Module (SIM)
Base Station Subsystem (BSS)
a) Base Transceiver station (BTS) b) Base station controller (BSC) Network Switching Subsystem (NSS)
a) Mobile Switching Center (MSC) b) Home Location Register (HLR) c) Visitor Location Register (VLR) d)
Authentication Center (AUC)
e)
Equipment Identity Register (EIR) 35
System Architecture of Mobile Station (MS):
The Mobile Station is made up o f two entities: a) Mobile Equipment (ME) b) Subscriber Identity Module (SIM)
Mobile Equipment (ME):
a) Portable, vehicle mounted, hand held device b) Uniquely identified by an IMEI (International Mobile Equipment Identity) c) Voice and data transmission d) Monitoring power and signal quality of surrounding cells for o ptimum handover e) Power level: 0.8W ± 20 W f) 160 character long SMS.
Subscriber Identity Module (SIM):
a) Smart card contains the International Mobile Subscriber Identity (IMSI) b) Allows user to send and receive calls and receive other subscribed services c) Encoded network identification details -Key Ki, Kc and A3, A5 and A8
algorithms
d) Protected by a password or PIN e) Can be moved from phone to phone ± contains key information to activate the phone
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System Architecture of Base Station (BSS):
Base Station Subsystem is composed of two parts a) Base Transceiver Station (BTS) b) Base Station Controller (BSC)
Base Transceiver Station (BTS):
a) Encodes, encrypts, multiplexes, modulates and feeds t he R F signals to the antenna. b) Frequency hopping c) Communicates with Mobile station and BSC d) Consists of Transceivers (TRX) units
Base Station Controller (BSC):
a) Manages Radio resources for BTS b) Assigns Frequency and time slots for all MS¶s in its area c) Handles call set up d) Transcoding and rate adaptation functionality e) Handover for each MS f) Radio Power control g) It communicates with MSC and BTS
System Architecture of Network Switching Subsystem (NSS): Mobile Switching Center (MSC):
a) Heart of the network b) Manages communication between GSM and other networks c) Call setup function and basic switching d) Call routing
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e) Billing information and collection f) Mobility management - Registration - Location Updating Home Location Registers (HLR)
a) Permanent database about mobile subscribers in a large service area (generally one per GSM network operator) b) Database contains IMSI, MISDN, prepaid/postpaid, roaming, supplementary services.
Visitor Location Registers (VLR)
a) Temporary database which updates whenever new MS enters its area, by HLR database b) Controls those mobiles roaming in its area c) Reduces number of queries to HLR
Authentication Center (AUC)
a) Protects against intruders in air interface b) Maintains authentication keys and algorithms and provides security triplets (RAND, SRES, Kc) c) Generally associated with HLR
Equipment Identity Register (EIR)
Database that is used to track handsets using the IMEI (International Mobile Equipment Identity) a) Made up of three sub-classes: The White List, The Black List and the Gray List b) Only one EIR per PLMN 38
Accessing a GSM network
In order to gain access to
GSM
services, a user needs three things:
A billing relationship with a mobile phone operator. This is usually either where services are paid for in advance of them being consumed (prepaid), or where bills are issued and settled after the service has been consumed (po stpaid).
A mobile phone that is GSM compliant and operates at the same frequency as the operator. Most phone companies sell phones from third-party manufacturers.
A SIM (³Subscriber Identity Module´) card, which is activated by the operator once the billing relationship, is established. After activation the card is then pro grammed with the subscriber's MSISDN (³Mobile Subscriber Integrated Services Digital Network Number´) (the telephone number). Personal information such as contact numbers of friends and family can also be stored on the SIM by the subscriber.
After subscribers sign up, information about their identity (telephone number) and what services they are allowed to access are stored in a "SIM record" in the Home Location Register (HLR). Once
the SIM card is loaded into the phone and the phone is powered on, it will search for the
nearest mobile phone mast (also called a Base Transceiver station (BTS)) with the strongest signal in the operator's Frequency band. If a mast can be successfully contacted, then there is said to be coverage in the area. The phone then identifies itself to the network through the control channel. Once this is successfully completed, the phone is said to be attached to t he network. The key feature of a mobile phone is the ability to receive and make calls in any area where coverage is available. This is generally called roaming from a customer perspective, but also called visiting when describing the underlying technical process. Each geographic area has a database called the Visitor Location register (VLR), which contains details of all the mobiles currently in that area. Whenever a phone attaches, or visits, a new area, the V isitor Location Register must contact the Home Location Register to obtain the details for that phone. The current cellular location of the phone ( i.e. which BTS it is at) is entered into the VLR record and will be used during a process called paging when the GSM network wishes to locate the mobile phone. Every SIM card contains a secret key, called the Ki, which is used to provide authentication and encryption services. This is useful to prevent t heft of service, and also to prevent "o ver the air" 39
snooping of a user's activity. The netwo rk does this by utilizing the Authentication Centre and is accomplished without transmitting the key directly.
Every GSM phone contains a unique identifier (different from the phone number), called the International Mobile Equipment Identity (IMEI). This can be found by dialing *#06#. When a phone contacts the network, its IMEI may be checked against the Equipment Identity register to locate stolen phones and facilitate monitoring.
Voice calls:
Outgoing calls
1-MS sends dialed number to BSS 2-BSS sends dialed number to MSC 3, 4 - MSC checks VLR if MS is allowed the requested service. If so, MSC asks BSS to allocate resources for call. 5 -MSC routes the call to
GMSC
6 -GMSC routes the call to local exchange o f called user 7, 8, 9, 10 -Answer back (ring back) tone is routed from called user to MS via GMSC, MSC, BSS
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Incoming calls
1. Calling a GSM subscribers 2.
Forwarding
call to GSMC
3. Signal Setup to HLR 4. 5. Request MSRN from VLR 6.
Forward
responsible MSC to
7.
Forward
Call to current MSC
8. 9.
Get
GMSC
current status of MS
10. 11. Paging of MS 12. 13. MS answers 14. 15. Security checks 16. 17. Set up connection
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R outing the call
When the HLR receives this query message, it determines whether the call should be ro uted to another number (called a d ivert), or if it is to be routed directly to the mobile.
If the owner of the phone has previously requested that all incoming calls be d iverted to another number, known as the Call Forward Unconditional (CFU) Number, then this number is stored in the Home Location Register. If that is the case, then the CFU number is returned to the Gateway MSC for immediate routing to t hat destination.
If the mobile phone is not currently associated with a Visited Location Register (because the phone has been turned off) then the Home Location Register returns a number known as the Call Forward Not Reachable (CF NRc) number to the Gateway MSC, and the call is forwarded there. Many operators may set this value automatically to the phone's voice mail number, so that callers may leave a message. The mobile phone may sometimes override the default setting.
Finally,
if the Home Location Register knows that the phone is roaming in a
particular Visitor Location Register area, then it will request a temporary number (ca lled an MSRN) from that VLR. This number is relayed back to the Gateway MSC, and then used to route the call to the MSC where the called phone is roaming.
4. THIRD GENERATION 3G TECHNOLOGY Third generation (3G) networks were conceived from the Universal Mobile Te lecommunications Service (UMTS) concept for high speed networks for enabling a variety of data intensive applications. 3G is the next generation of mobile communications systems. It enhances the services such as multimedia, high speed mobile broadband, internet access with the ability to view video footage on your mobile handset. With a 3G phone and access to the 3G network you can make video calls, watch live TV, access the high speed internet, receive emails and download music tracks, as well as the usual voice call and messaging services found o n a mobile phone, like person to person video, live streaming, downloadable video of enterta inment, news, current affairs and sport content and video messaging Data Speed: The data speed of 3G is determined based on a combination of factors including the chip rate, channel structure, power control, and synchronization.
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3G is the short form for third-generation technology. It is one o f the popular mobile phone standards. The services utilizing 3G provide the ability to transmit both voice data such as calls and non-voice data such as instant messaging, email and video t elephony at the same time. Japan was the first country to introduce 3G on a wide scale commercially. In 2005, almost 40 per cent of the subscribers in Japan used 3G services. On the technical front, 3G services are wide area cellular telephone networks 43
9.
BSNL¶s IPTV First
started in Japan in 2002.
Popular in France, South Korea, Germany, Hongkong etc. France
is leading in IPTV .
IPTV services may be classified into three main gro ups:
Live Television: with or without interactivity related to the current T V show
Time-Shifted Programming: catch-up TV (replays a TV show that was broadcast hours or days ago), start-over TV (replays the current T V show from its beginning)
Video on Demand (VOD): browse a catalog of videos, not related to TV programming
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CONCLUSION
Training at BSNL helped me to attain knowledge about the various processes involved. It was very informative. I learnt quite a lot about electronic exchange, Internet, WLL, Mobile GSM & 3G, and the basics of processing Exchange. I also got firsthand knowledge of how a Telephone Exchange works. It¶s an unforgettable experience for me as it made me get accustomed to the professional environment. It helped me to develop an individual personality and boosted my confidence.
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