WELCOME TRAINING REPORT ON TELECOMMUNICATION SUBMITTED TO, ECE DEPTT. SUBMITTED BY, PRAKASH KUMAR ARYA ROLL NO. 1608214 GROUP:- A BRANCH:- ECE YEAR:- 3rd Yr. INTRODUCTION TO BSNL BSNL: Bharat Sanchar Nigam Limited was formed in year 2000 and took over the service providers role from DoT. Today, BSNL has a customer base of over 9 crore and is the fourth largest integrated telecom operator in the country. BSNL is the market leader in Broadband, landline and national transmission network. BSNL is also the only operator covering over 5 lakh village with telecom connectivity. Area of operation of BSNL is all India except Delhi & Mumbai. INTRODUCTION Governments also need to intervene for ensuring fair competition and the best value for money for its citizens. This handouts gives exposure on the Telecom Environment in India and also dwells on the role of international bodies in standardizing and promoting Telecom Growth in the world. Institutional Framework It is defined as the systems of formal laws, regulations, and procedures, and informal conventions, customs, and norms, that broaden, mold, and restrain socio-economic activity and behaviour. country has been divided into units called Circles, Metro Districts, Secondary Switching Areas (SSA), Long Distance Charging Area (LDCA) and Short Distance Charging Area (SDCA). Major changes in Telecommunications in India Its began in the 1980s. The initial phase of telecom reforms began in 1984 with the creation of Center for Department of Telematics (C-DOT) for developing indigenous technologies and private manufacturing of customer premise equipment. Soon after, the Mahanagar Telephone Nigam Limited (MTNL) and Videsh Sanchar Nigam Limited (VSNL) were set up in 1986. Major changes in Telecommunications in India The Indian telecom sector was setting up of an independent regulatory body in 1997 – the Telecom Regulatory Authority of India (TRAI), to assure investors that the sector would be regulated in a balanced and fair manner. In 2000, DoT corporatized its services wing and created Bharat Sanchar Nigam Limited. Major changes in Telecommunications in India With the TRAI Act of 2000 that aimed at restoring functional clarity and improving regulatory quality and a separate disputes settlement body was set up called Telecom Disputes Settlement and Appellate Tribunal (TDSAT) to fairly adjudicate any dispute between licensor and licensee, between service provider, between service provider and a group of consumers. Major changes in Telecommunications in India In October 2003, Unified Access Service Licenses regime for basic and cellular services was introduced. This regime enabled services providers to offer fixed and mobile services under one license. Indian telecom has seen unprecedented customer growth crossing 600 million connections. India is the fourth largest telecom market in Asia after China, Japan and South Korea. The Indian telecom network is the eighth largest in the world and the second largest among emerging economies. Lesson Plan Institutional Mechanism and role & Telecom Eco system National DOT, TRAI,TDSAT, TEC,CDOT International Standardization bodies- ITU,APT,ETSI etc. Licensed Telecommunication services of DOT Various Trade associations, Network Operators, Manufacturers, service providers, service provisioning and retailing, billing and OSS Job opportunities in telecom Market, government and statutory bodies. TELECOMMUNICATION INTRODUCTION Computer network A communications, data exchange, and resourcesharing system created by linking two or more computers and establishing standards, or protocols, so that they can work together Telecommunication system - Enable the transmission of data over public or private networks (voice, data, graphics, video…) TELECOMMUNICATIONS-VOICE Voice Communications Require:- 1. 2. 3. 4. A source device A switching system A data channel A destination device The line remains open for the duration of the call Requires a dedicated connection Telecommunications - data Data communications – data traffic Data traffic on the Internet doubles every 100 days. Does not “grab the line” during transmission Uses packet switching technology Ways to describe a network… Type of traffic (voice or data) Type of signal (analog or digital) Type of transmission mode (Simplex…) Geographic area covered (LAN, WAN...) Architecture - peer-to-peer, client/server Physical topology (Bus, Star…) Protocols - Ethernet, Transmission Control Protocol/Internet Protocol (TCP/IP) Transmission medium (guided or unguided) Types of Signals Analog Continuous sine wave over a certain frequency range positive voltage = 1 negative voltage = 0 Digital Discrete burst of electric energy on = 1 off = 0 Most phone lines use analog signaling Converting Signals Computers can only process digital signals If data is transmitted using analog signaling over a phone line, it must be converted into a digital signal before the computer can process it…… Converting Signals Modems Modulation - converting digital signals into analog form DEModulation - converting analog signals back into digital form Transmission Modes Performance can be measured by the mode of the connection. Simplex transmission, messages can be carried in only one direction. Half-duplex, messages can be carried in both directions just not simultaneously. Full-duplex, messages can be carried in both directions simultaneously. LOGICAL TOPOLOGIES (protocols) Protocol - a standard that specifies the format of data as well as the rules to be followed during transmission A communication protocol is essentially a set of codes or conventions used for facilitating communications between hardware and software. Interoperability - the capability of two or more computer systems to share data and resources, even though they are made by different manufacturers Protocol – how it works common set of rules that allow different components in a network to talk to each other handshaking protocol identify each device secure attention of other device transmission protocol verify correct receipt of message send re-transmit message if necessary recover error and re-transmit Some Protocols Ethernet - a physical and data layer technology for LAN networking IP or Internet Protocol directs packets on the Internet. TCP or Transmission control protocol puts the packets in their correct sequence. HTTP or hyper text transfer protocol is used to transmit web pages over the Internet. Mobile IP provides IP routing for mobile devices. Voice over IP (VoIP) - uses TCP/IP technology to transmit voice calls over long-distance telephone lines TRANSMITTING AND RECEIVING DEVICES THE HARDWARE: Network adapters Modems Repeaters Wiring concentrators, hubs, and switches Bridges, routers, and gateways Microwave transmitters Infrared and laser transmitters Cellular transmitters Wireless LAN transmitters NETWORKING BASICS Bandwidth - indicates how much information can be carried in a given time period (usually a second) over a wired or wireless communications link. Measured in megabits per second cdma2000 Radio Access Network Outline cdma2000 network architecture Call processing states and call flows CDMA evolution Essential elements in a CDMA system Power Control Mobility management Handoffs Registration Roaming Network Architecture Packet Network PSTN PDSN MSC BSC Ericsson UCSD Black Mountain A CDMA Network architecture consists of the following components: •Mobile station •Radio Base Station (RBS) •Base Station Controller (BSC) •Mobile Switching Center (MSC) •Public Switch Telephone Network •PDSN as an IP Gateway Call Processing - Pilot First MS monitors Pilot channel for Initial acquisition Channel estimation Detection of multipaths for rake receiver Handoffs Pilot Ch Call Processing - Sync Pilot channel is transmitted at all times by the base station. MS uses it to lock to Synch Channel to Synchronize to CDMA system time Obtain configuration parameters such as Protocol Revision (P-REV) Network Identifier (NID) Pilot PN offset Long-code state Paging channel data rate Sync Ch Call Processing - Paging MS decodes the Paging Channel with the information received from the Sync Channel. Paging channel provides Overhead messages: systems parameter, access parameter, neighbor list, channel list Mobile directed messages: page request, SMS Paging Ch Call Processing – Access MS uses Access channel to originate a call or to respond to a page request. Access Channel is used in a random access fashion. Access Ch Call Processing - Traffic Base station assigns a forward and reverse traffic channel to the mobile when it is in conversation Traffic Channel conveys signaling and traffic information When MS is on traffic channel it no longer listens to paging channel or uses the access channel Mobile Station States Power Up Call origination or page response Synchronization Initialization State Paging Loss Idle State Access State Page response completed End of call Traffic State Initialization: •Acquire pilot channel of the selected CDMA system within 20 secs (not standardized) •Process synch channel for synchronization (long code and CDMA timing) Idle: •Monitor paging channel for overhead and mobile directed messages •Move to access state to originate a call or respond to a page request Access: •MS sends messages to the base station and gets responses in the paging channel •This can be a call origination or a page response Traffic: •MS communicates with the base station using forward and reverse traffic channels •Paging and access channels are no longer monitored •Alert with info is used for order message Mobile Originated Voice Call Flow Access Ch. MSC BSC Overhead Info MS Paging Ch. Origination Msg Paging Ch. BS Ack Order CM Service Request Fwd Traffic Ch. Paging Ch. Rev Traffic Ch. Null Frames SCCP Connection Cfm Channel Assign Msg Preamble Fwd Traffic BS Ack Order Ch. Rev Traffic Ch. MS Ack Order Fwd Traffic Ch. Assignment Request Service Connect Rev Traffic Ch. Service Conn Cmplt Assignment Complete CDMA Evolution (1/3) IS-95A (2G) First CDMA protocol, published in May’99 14.4/9.6 kbps circuit/packet data IS-95B (2.5G) Most analog information is removed Some technical corrections New Capabilities, such as higher data rate 64 kbps packet data CDMA Evolution (2/3) CDMA2000 1X High speed data (144 kbps packet data with Mobile IP) Coding (Turbo) and Modulation (Hybrid QPSK) New dedicated and common channels Enhanced Power Control Reverse link detection Forward link modulation CDMA Evolution (3/3) 1X EV-DO (1xRTT Evolution for high-speed integrated Data Only) The objective is to provide the largest practical number of users to run high-speed packet data applications 2.4 Mbps packet data 1X EV-DV (1xRTT Evolution for high-speed integrated Data and Voice) Voice and High Speed Data mixed on one carrier Backward-compatible with CDMA2000 1X 3.1 Mbps packet data Multiple Access Methods Dedicated band during entire call Each user transmits at the same time, at the same frequency with a unique code Certain frequency, time-slotted Frequency Re-use Patterns B G C A F B G D E A E A F FDMA and TDMA vs. A A A A A A A A A CDMA A A Channelization Channelization is provided by orthogonal Walsh codes cdma2000 uses variable length Walsh codes for supplemental channel data services Walsh codes can be of length 8, 16, 32, 64, and 128 Walsh Codes Walsh codes are orthogonal to each other The shorter the code the higher the data rate since the chip rate is kept constant 1 10 1001 11 1010 1100 1111 Use of Multipath sin CDMA Systems FDMA/TDMA (narrow-band) multipath hurts equalizers are used to cancel multipath CDMA (wide-band) can discriminate between the multipath arrivals Rake receivers are used to combine multipath signals to reduce error rate at the receiver Power Control – Algorithm Capacity is maximized By having each user transmitting just sufficient SNR to maintain a target FER Open Loop Estimate Initial transmit power level for the mobile is determined by the received pilot strength Closed Loop Power Control Base station controls the power level on the mobile by the received quality information. Mobility management A CDMA system provides mobility: Handoff – continuity of the service across adjacent cells Registration – locating the mobile user Roaming – continuity of the service across different service providers Handoff Handoffs between cells are supported while the mobile is in traffic or idle MS continuously keeps searching for new cells as it moves across the network MS maintains active set, neighbor set, and remaining set as well as candidate set There are 4 types of handoffs: Idle Handoff Access Handoff Soft/Softer Handoff Hard Handoff Soft Handoff Black Mountain Both cells have the same frequency PDSN MSC BSC Ericsson UCSD Soft Handoff Make-before-break Both cells are at the same frequency Reduces number of call drops Increases the overall capacity Mobile transmit power is reduced Voice quality near the cell boundaries are improved MS reports the SNR of the candidate sets Hard Handoff Break-before-make Handoff between different frequencies, non-synchronized or disjoint cells which are controlled by different BSCs Registration It is sufficient to know the cell or the region that a MS is active for routing purposes Mobile station identifier, desired paging slot cycle, and registration type is conveyed Cell/LAC based paging is preferred to flood paging Registration Types Autonomous Registration: power-up, power-down, timer-based, distance-based, zone-based registration. Parameter-change registration Ordered registration Implicit registration Traffic channel registration Roaming Users that are outside their home area can receive service from another system by paying some additional charges Mobile station can be: Home state (not roaming) Network roaming System roaming Network 2 Network 1 System Network 3 Fibre used in Telecom & Their Characteristics Brief History In 1880, Alexander Graham Bell patented an optical telephone system, which he called the Photophone. By 1970 Corning Glass invented fiber-optic wire or "optical waveguide fibers" which was capable of carrying 65,000 times more information than copper wire. Prof. Kao was awarded half of the 2009 Nobel Prize in Physics for "groundbreaking achievements concerning the transmission of light in fibers for optical communication". Today more than 80 percent of the world's longdistance voice and data traffic is carried over opticalfiber cables Fiber-Optic Applications FIBRE OPTICS: The use and demand for optical fiber has grown tremendously and optical-fiber applications are numerous Telecommunication applications are widespread, ranging from global networks to desktop computers. These involve the transmission of voice, data, or video over distances of less than a meter to hundreds of kilometers, using one of a few standard fiber designs in one of several cable designs ADVANTAGES OF FIBRE OPTICS SPEED: Fiber optic networks operate at high speeds - up into the gigabits BANDWIDTH: Large carrying capacity DISTANCE: Signals can be transmitted further without needing to be "refreshed" or strengthened. RESISTANCE: Greater resistance to electromagnetic noise such as radios, motors or other nearby cables. MAINTENANCE: Fiber optic cables costs much less to maintain. Fiber Optic System Information is Encoded into Electrical Signals. Electrical Signals are Converted into light Signals. Light Travels Down the Fiber. A Detector Changes the Light Signals into Electrical Signals. Electrical Signals are Decoded into Information. Inexpensive light sources available. Repeater spacing increases along with operating speeds because low loss Fibres are used at high data rates. Principle of Operation - Theory Total Internal Reflection The Reflection that Occurs when a Light Ray Travelling in One Material Hits a Different Material and Reflects Back into the Original Material without any Loss of Light Speed of light is actually the velocity of electromagnetic energy in vacuum such as space. Light travels at slower velocities in other materials such as glass. Light travelling from one material to another changes speed, which results in light changing its direction of travel. This deflection of light is called Refraction Angle of incidence ø1 ø1 n1 n2 ø2 Light is bent away from normal n1 n2 ø1 ø2 Light does not enter second material n1 n2 Angle of reflection ø2 PROPAGATION OF LIGHT THROUGH FIBRE The optical fibre has two concentric layers called the core and the cladding. The inner core is the light carrying part. The surrounding cladding provides the difference refractive index that allows total internal reflection of light through the core. The index of the cladding is less than 1%, lower than that of the core. Most fibres have an additional coating around the cladding. This buffer coating is a shock absorber and has no optical properties affecting the propagation of light within the fibre. Specific characteristics of light depends on The size of the fibre. The composition of the fibre. The light injected into the fibre. Jacket Jacket Cladding Core Cladding (n2) Core (n2) Cladding Jacket Light at less than Angle of Angle of critical angle is incidence reflection absorbed in jacket Light is propagated by total internal reflection Diameters of the core and cladding 125 8 125 50 Core 125 62.5 Cladding Typical Core and Cladding Diameters 125 100 FIBRE TYPES Step Index Graded Index By this classification there are three types of fibres : Multimode Step Index fibre (Step Index fibre) Multimode graded Index fibre (Graded Index fibre) Single- Mode Step Index fibre (Single Mode Fibre) STEP-INDEX MULTIMODE FIBER large core, up to 100 microns in diameter. As a result, some of the light rays that make up the digital pulse may travel a direct route, whereas others zigzag as they bounce off the cladding. These alternative pathways cause the different groupings of light rays, referred to as modes, to arrive separately at a receiving point. The pulse, an aggregate of different modes, begins to spread out, losing its well-defined shape. GRADED-INDEX MULTIMODE FIBER Contains a core in which the refractive index diminishes gradually from the center axis out toward the cladding. The higher refractive index at the center makes the light rays moving down the axis advance more slowly than those near the cladding Also, rather than zigzagging off the cladding, light in the core curves helically because of the graded index, reducing its travel distance. GRADED-INDEX MULTIMODE FIBER The shortened path and the higher speed allow light at the periphery to arrive at a receiver at about the same time as the slow but straight rays in the core axis. The result: a digital pulse suffers less dispersion. SINGLE-MODE FIBER has a narrow core (eight microns or less), and the index of refraction between the core and the cladding changes less than it does for multimode fibers. Light thus travels parallel to the axis, creating little pulse dispersion. Telephone and cable television networks install millions of kilometers of this fiber every year OPTICAL FIBRE PARAMETERS Wavelength. Frequency. Window. Attenuation. Dispersion. Bandwidth Cable Components Component Buffer Function Protect fibre From Material Nylon, Mylar, Plastic Outside Facilitate Stranding Central Member Temperature Stability Steel, Fibreglass Anti-Buckling Primary Strength Member Tensile Strength Aramid Yarn, Steel Contain and Protect Cable Jacket Cable Core PE, PUR, PVC, Teflon Abrasion Resistance Cable Filling Prevent Moisture Water Blocking INTRODUCTION TO BROADBAND SERVICES Overview Broadband service in growth of GDP and enhancement in quality of life through societal applications including tele-education tele-medicine, e-governance, entertainment employment generation by way of high speed access to information and web-based communication, Overview Broadband refers to greater bandwidth-or transmission capacity of a medium Broadband technology will allow for high-speed transmission of voice, video, and data over networks like the Internet Currently, high speed Internet access is available from 64 kbps onwards and an always-on high speed Internet access at 128 kbps is considered as ‘Broadband’ ; There are no uniform standards for Broadband connectivity and various countries follow various standards. “Broadband” Is... High Speed Megabits: Millions of bits per second … at least in one direction Always on Continuous connection to the outside world Bidirectional High speed from the home as well as to the home Can “see” the home from the outside BROADBAND CONNECTIVITY:DEFINITION ‘An ‘always-on’ data connection that is able to support interactive services including Internet access and has the capability of the minimum download speed of 256 kbps to an individual subscriber from the Point Of Presence (POP). Broadband Different technologies Narrowband 2.4 kbps – 128kbps Broadband 256kbps – 8000kbps LAN 1000kbps – 100Mbps / Giga Ethernet NETWORK EVOLUTION - VOICE+ DATA + TV & VIDEO Broadcast TV Head-end ISP NOC B-RAS Encoders OSS/BSS ISP Infrastructure ` Internet TV & VoD RAS POTS/Paypho ne ISDN BRI E1 leased lines Class 5 LE LE TV & VOD STB High-Speed Internet Wi-Fi IP DSLAM ADSL access SHDSL access Central Video Servers Edge Video Servers GE DLC DLC Cu OSP GE L2 Ring IP-DSLAM RSU IPDSLAM Edge Video Servers IP-DSLAM xDSL CP Home Gateway E Voice + Video Phone Dial-up Internet BROADBAND APPLICATIONS 1. Personal Services High Speed Internet Access Multimedia 2. Govts. Public services E-governance E-education Tele-medicine 3. Commercial services E-commerce Corporate Internet Videoconferencing (256 Kbps and above) 4. Video & Entertainment services Broadcast TV Video on Demand Interactive gaming Music on Demand Online Radio BROADBAND APPLICATIONS VARIOUS ACCESS TECHNOLOGIES DSL on copper loop Optical Fiber Technologies Cable TV Network Satellite Media Terrestrial Wireless Future Technologies Wireline Broadband Access Technologies In the domain of wide area network access, there are numerous wireline technology options that are presently competing for market share and acceptance These technology options originate from both the WAN and LAN environments and include e.g. ISDN, ATM, switched Ethernet Frame Relay, several technologies for data transmission over coaxial (CATV) cable, and the family of Digital Subscriber Line technologies. Digital Subscriber Lines (DSL) on copper loop DSL has proved to be an important technology for provisioning of Broadband services through the copper loop. The owners of copper loop have to be given a high priority because their role is critical as key drivers in the Broadband service market using DSL. BSNL and MTNL as well as other access providers are expected to aggressively use their copper loop infrastructure for providing Broadband services through this technology OPTICAL FIBRE TECHNOLOGIES It provides nearly unlimited bandwidth potential and is steadily replacing copper network specially in intra-city backbone networks. This is being deployed in commercial buildings and complexes and some metros / big cities having high-density potential broadband subscribers. The fiber based models are future proof as they are able to provide huge amounts of bandwidth in the last mile as well as provide a true IP and converged network that can deliver high quality voice, data and video Cable TV Network Cable TV network can be used as franchisee network of the service provider for provisioning Broadband services. The cable network was designed to deliver TV signals in one direction from the Head-End to the subscribers homes Operators had to upgrade the cable network so that signals could flow in both directions One spectrum is used for the signals that move from the Head-End towards the cable subscriber Cable TV Network GSM Architecture Network Components Switching System(SS) Base Station System(BSS) OSS HLR B T S PSTN ISDN B T S BSC BSC MSC VLR A Interface B T S Air interface ( A-bis interface MSC VLR Data Networks ERICSSON’S GSM SYSTEM ARCHITECTURE Switching System MIN SDP EIR AUC HLR ILR SCF BGW Other PLMNsz Public Data Networks MSC/VLR PSTN ISDN GMSC DTI MC (MXE) SOG SSF OSS Base Station System TRC BSC RBS Network Structure LOCATION AREA A LA is defined as a group of cells. Within the network, a subscriber’s location is known by the LA which they are in. The identity of the LA in which an MS is currently located is stored in the VLR. (LAI) Network Structure MSC Service Area An MSC Service Area is made up of LAs and represents the geographical part of the network controlled by one MSC. MSC Service Area LA2 LA1 VLR MSC LA4 LA5 LA3 LA6 Network Structure PLMN SERVICE AREA A PLMN service area is the entire set of cells served by one network operator and is defined as the area in which an operator offers radio coverage and access to its network. Network Structure GSM SERVICE AREA The GSM service area is the entire geographical area in which a subscriber can gain access to a GSM network. Relation between areas in GSM Location CellArea Location Area MSC Service Area PLMN Service Area GSM Service Area Mobile Station GSM MSs consist of: • Mobile Equipment • Subscriber Identity Module Functions of Mobile Station Voice and data transmission& receipt Frequency and time synchronization Monitoring of power and signal quality of the surrounding cells Provision of location updates even during inactive state Functions of Mobile Station Voice and data transmission& receipt Frequency and time synchronization Monitoring of power and signal quality of the surrounding cells Provision of location updates even during inactive state SIM Fixed data stored for the subscription: IMSI, Authentication Key, Ki Security Algorithms:kc,A3,A8 PIN&PUK SIM •Temporary network data: Location area of subscriber and forbidden PLMNs •Service data: language preference, advice of charge KEY TERMS An MS can have one of the following states : Idle: the MS is ON but a call is not in progress. Active: the MS is ON and a call is in progress. Detached: the MS is OFF. Network Identities MSISDN IMSI TMSI MSRN IMEI MSISDN Mobile Station ISDN Number The MSISDN is registered in the telephone directory and used by the calling party for dialing. MSISDN shall not exceed 15 digits. NDC--National Destination Code SN--Subscriber Number 1 to 3 digits Variable Variable CC NDC MSISDN : not more than 15 digits SN IMSI International mobile subscriber Identity The IMSI is an unique identity which is used internationally and used within the network to identify the mobile subscribers. The IMSI is stored in the subscriber identity module (SIM), the HLR, VLR database. IMSI 3 digits 3 digits MCC Not more than 9 digits MNC MSIN NMSI IMSI : Max. 15 digits MCC--Mobile Country Code, MNC--Mobile N/W Code, MSIN--Mobile Station Identification Number NMSI--National Mobile Station Identity, assigned by Individual Administration. Mobile station Identification Number. It identifies the subs. In a PLMN. First 3 digit identifies the Logical HLRid of Mobile subs. IMEI International Mobile Equipment Identity The IMEI is an unique code allocated to each mobile equipment. It is checked in the EIR. IMEI check List White List Grey List Black List GSM Applications Mobile telephony GSM-R Telemetry System - Fleet management - Automatic meter reading - Toll Collection - Remote control and fault reporting of DG sets Value Added Services Future Of GSM 2nd Generation GSM -9.6 Kbps (data rate) 2.5 Generation ( Future of GSM) HSCSD (High Speed ckt Switched data) Data rate : 76.8 Kbps (9.6 x 8 kbps) GPRS (General Packet Radio service) Data rate: 14.4 - 115.2 Kbps EDGE (Enhanced data rate for GSM Evolution) Data rate: 547.2 Kbps (max) 3 Generation WCDMA (Wide band CDMA) Data rate : 0.348 – 2.0 Mbps THANKS !