INTRODUCTION TO BROADBAND TECHNOLOGY

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INTRODUCTION TO BROADBAND SERVICES 

Overview

With the evolution of computer networking and packet switching concept a new era of integrated communication has emerged in the telecom world. 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 tool for the conveyance of information, and thus can be critical to the development process. Telecommunications has become one of the most important infrastructures that are very essential to the socio-economic well being of any nation.

As the Internet market continues to explode, demand for greater bandwidth and faster connection speeds have led to several technological approaches developed to provide broadband access to all consumers. The demand for high-speed bandwidth is growing at a fast pace, driven mostly by growth in data volumes as the Internet and related networks become more central to business operations.

The rapid growth of distributed business applications; the proliferation of private networks, e-commerce, and bandwidth-intensive applications (such as multimedia, videoconferencing, and video on demand) generate the demand for bandwidth and access network.

Moreover, an increasing number of consumers in this area further leads to a demand for carrying these applications faster and reliable. Essentially, the broadband revolution is about a huge increase in the range of services that can be offered via the Internet and digital television. It promises a new age in entertainment and communications, as well as a major boost for e-commerce. To meet this explosive demand for bandwidth and to capitalize on this growing data opportunity, many data competitive local-exchange carriers are aggressively targeting small businesses, SOHOs, and teleworkers in the selected areas of the country in which they are operating.

A concept of broadband services and the means of access technologies to bridge the customer and service provider is emerged out through out the world. "Broadband" refers to high-speed Internet access. Traditionally, residential subscribers have accessed the Internet by attaching a modem to their phone line and placing a local call to their ISP. This "dial-up" or "narrow band" service has a number of constraints on speed. Most commercial modems can achieve a maximum speed over the phone line of 56 kilobits per second (kbps). As a result, many different companies have worked to develop "broadband" or high-speed access. These broadband services will allow Internet subscribers to send or receive video and audio content of digital quality, to download interactive graphic-rich WebPages, and to allow Internet entrepreneurs to bring new services to market that take advantage of speeds that will make the Internet truly interactive in real time. In short, broadband promises to revolutionize the Internet in the same way that the introduction of the Internet revolutionized communication.

In deploying these broadband services, service providers are developing whole new ways to access the Internet. The Internet was never designed to handle the

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amount of traffic that we are seeing today. The increasing penetration of broadband access and the demand for multimedia applications is exacerbating this problem. The increasing importance of the Internet and the importance of delivering Web content quickly and reliably have put strains on the network. As broadband penetration increases, users will demand higher-quality content such as more streaming media. High-speed access has become as important as a two-car garage, fireplace, kitchen, or a nursery in a new home. For builders, high-speed access is a way to have a continuing revenue stream even after they have sold the houses. In most of the places built, the builders retain a small ownership interest. Many builders are weighing revenue-sharing arrangements with broadband access companies that will wire all new developments as well as existing ones, similar to the deals developers have struck to wire office buildings with broadband providers.

Definition of broadband

Broadband is the nonspecific term for high-speed digital Internet access.  To state the obvious, ‘broadband’ indicates a means of connectivity at a high or ‘broad’ bandwidth.

According to the Federal Communications Commission (FCC), high-speed Internet service is, “(a service) that provide(s) the subscriber with transmissions at a speed in excess of 200 kilobits per second (kbps) in at least one direction.” The FCC further defines advanced broadband services as “providing the subscriber with transmission speeds in excess of 200 kbps in each direction.

Another definition of broadband has been put forward in a prepublication report issued by The National Academies. In this report, Broadband, Bringing Home the Bits, the Academy states that broadband should be defined “in a dynamic and multidimensional fashion.” The Academies then defined broadband as Local access link performance should not be the limiting factor is a user’s capability for running today’s applications. Broadband services should provide sufficient performance – and wide enough penetration of services reaching that performance level – to encourage the development of new applications.”

Recognizing the potential of ubiquitous Broadband service in growth of GDP and enhancement in quality of life through societal applications including tele-education, tele-medicine, e-governance, entertainment as well as employment generation by way of high speed access to information and web-based communication, Government have finalised a policy to accelerate the growth of Broadband services. In India, DoT has issued a Broadband policy in 2004. Keeping in view the present status, Broadband connectivity is defined at present as: - 

“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 kilo bits per second (kbps) to an individual subscriber from the Point Of Presence (POP) of the service provider intending to provide Broadband service where multiple such individual Broadband connections are aggregated and the subscriber is able to access these interactive services including the Internet through this POP.  The interactive services will exclude any services for which a separate licence is specifically required, for example, real-time voice transmission, except to the extent that it is presently permitted under ISP licence with Internet Telephony.”

It reflects that: -

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o One of the latest trends in enhancing communication systems involves broadband technology

o Broadband refers to greater bandwidth-or transmission capacity of a medium

o Broadband technology will allow for high-speed transmission of voice, video, and data over networks like the Internet

The Government of India is making great attempts to create a conducive environment for promoting Broadband services in the country. To Strengthen Broadband Penetration the Department of Telecommunication, Government of India, has formulated a Broadband Policy whose main objectives are to: 

Establish a regulatory framework for the carriage and the content of information in the scenario of convergence.

Facilitate development of national infrastructure for an information based society.

Make available broadband interactive multimedia services to users in the public network.

Provide high speed data and multimedia capability using new technologies to all towns with a population greater than 2 lakhs.

Make available Internet services at panchayat (village) level for access to information to provide product consultancy and marketing advice.

Deploy state of art and proven technologies to facilitate introduction of new services.

Strengthen research and development efforts in the telecom technologies.

 Broadband – enabling regulations

Some of the regulations proposed to achieve this end are listed below: - 

Promoting of facility-based competition by lowering market entry barriers.

Reducing charges for Rights of Ways (ROW).

Permitting infrastructure sharing among different service providers for optimum utilization.

Allowing the captive infrastructure of utility companies to be used for public broadband service.

Reducing the bottleneck in last-mile access by permitting deployment of alternative technologies like Cable TV network, Wireless etc.

Unbundling of local loop for DSL-based services.

 

Meaning of Broadband services

Broadband services are defined in various terms by different organization. Few of these are given below: -

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Original Bell System Definition

“A broadband channel is a communications channel having a Bandwidth greater than a voice-grade channel, and therefore capable of higher-speed data transmission.”

1996 Telecom Reform Act

Broadband services are capable of carrying “high-quality” voice, data, graphics, & video.

CCITT definition

A service requiring transmission channels capable of supporting rates greater than 1.5 Mbps or primary rate in ISDN or T1/E1 in digital terminology.

Practical Definitions

Residential

Currently means DSL, cable modem, or high speed wireless

Today’s services are web access, work-at-home, & steaming audio(Napster, etc)

Tomorrow, next generation video will be the killer app”(Son of Napster?)

Business

–Data, data, & data

–Today generally 1.5Mbps and up

–Tomorrow MUCH MORE than 1.5Mbps(100Mbps?)

Technology options for broadband services

Today's telecom industry is undergoing a bandwidth shortage driven mostly by the continuing explosion of the Internet and data markets. Demand comes from three primary sources: small and mid-sized businesses and small offices/home offices (SOHOs), consumers, and multiple-tenant units or in-building fiber builders and universities that are installing high-speed wireless connections throughout their campuses. Communication of data with different throughput is feasible by following different technologies

Narrow Band 2.4 kbps – 128kbpsBroadband 256kbps – 8000kbpsLAN 1000kbps – 100Mbps / Giga Ethernet

Various Access Technologies are used for the delivery of broadband services. Following are the major technologies adopted by the service providers: -

1. Wire line Technology

Digital Subscriber Lines (DSL) on copper loop

Optical Fibre Technologies

Cable TV Network

PLC (Power Line Communication       

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2. Wireless Technology

Satellite Media

Terrestrial Wireless

3G Mobile

Wi-Fi (Wireless Fidility)

WiMax

LMDS and MMDS

FSO (Free Space Optics)

Digital Subscriber Line Technology

Digital Subscriber Line (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. Digital Subscriber Line (DSL) is the next generation modem-like technology that allows for the transmission of voice, video and data over existing copper telephone lines at incredible megabit speeds.

The copper telephone lines are often referred to as the local loop or the last mile from the Exchanges to the end-user's home or business.

DSL provides high-speed Internet Access using regular telephone lines.

DSL provides dedicated bandwidth that can be up to 278 times faster than a 28.8 Kbps modem, 143 times faster than 56Kbps modem, 62 times faster than ISDN and up to 4 times faster than a E1 (T1) connection. It has the ability to move data over the phone lines at speeds up to 6Mb/s or six million bits per second, or 140 times quicker than the fastest analog modems available today (56,000 bits per second).

Typical DSL systems are:

High bit rate Digital Subscriber Line (HDSL) Asymmetrical Digital Subscriber Line (ADSL) Very high-speed Digital Subscriber Line (VDSL) Single-pair High Speed Digital Subscriber Line (SHDSL) ISDN based Digital Subscriber Line (DSL ISDN) Asymmetric Digital

Subscriber LineUsed for applications which require greater download bandwidth but require relatively little in opposite direction like Web browsing; File downloads.Broadband over copper wires using DSL works smoothly and covers longer distance according to the following data throughput.

Data Wire Size Distance1.5-2.0 0.5 5.5 Kms1.5-2.0 0.4 4.6 Kms6.1 0.5 3.7 Kms6.1 0.4 2.7 Kms

Optical fiber TechnologyIt 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

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in the last mile as well as provide a true IP and converged network that can deliver high quality voice, data and video. Following technologies are popular for broad band through OFC: -Hybrid Fiber Coaxial (HFC)

Fiber to the Curb (FTTC)

Fiber to the Home (FTTH)

Cable TV network Technology

Cable TV network Technology can be used as franchisee network of the service provider for provisioning Broadband services. It delivers high speed Internet services over Cable TV system. All responsibilities for ensuring compliance of terms & conditions of the license shall vest with the Licensee. The terms of franchise agreement between Licensee and his franchisee shall be settled mutually by negotiation between the two parties involved. A splitter splits the signal to TV outlets and the cable modem and Cable modem connects directly to the PC

PLC (Power Line Communication)

Power Line Communication is also known as BPL (Broadband over Power Line). A high frequency signal carries broadband IP on a utility power line.The high frequency signal is coupled directly onto the power line, not via modulation of the power waveform. The effective power is < 1 Watt.

Wireless Access Technologies

Wireless Personal Area Network (WPAN/ Bluetooth) (IEEE 802.15)

Wireless Local Area Network (WLAN / WiFi) (IEEE 802.11)

Wireless Metropolitan Area Network (WMAN / WiMax) (IEEE 802.16)

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Fixed Broadband Wireless Access (LMDS/MMDS)

Cellular Mobile Telephony (GSM-GPRS,EDGE / CDMA 2000 1x EVDO,EVDD) (3G-UMTS/WCDMA)

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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

4. Video & Entertainment services

Broadcast TV

Video on Demand

Interactive gaming

Music on Demand

Online Radio

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Video On Demand (VOD)

Allow subscribers to watch any pre-loaded program at anytime with full DVD like controls

Broadcast (BTV) & Time-shifted TV (TVOD)

Besides regular BTV services, TVoDSL provides subscribers with virtual DVD controls to pause, start, stop, rewind and fast forward live TV programs

Users also have the flexibility to watch any previous broadcasted programs without pre-recording (nPVR)

Pay-Per-View (PPV) /near-Video on Demand (nVOD)

Programs broadcast according to a pre-set schedule with subscribers having the option of watching and paying for individual programs

Interactive TV (iTV)

Video Phone / Video Conferencing / WebCam

Additional VAS (t-commerce, etc.)

Advertising [Targeted, Multicast]

BSNL’s Broadband Services

With the NIB – II project, BSNL is planning to rollout Broadband services in a big way across the country. The earlier forays in this regard did not really take off because of the inability of the franchisee to kickstart the equipment procurement and installation. However, with the current plans under the NIB-II project, BSNL will still be in a position to become the number one player in the segment in the country with its nation-wide rollout.

Broadband Services proposed to be rolled out

 The following services are proposed to be rolled out on the hardware and software platforms provided by NIB-II:

  High Speed Internet Access

1 Mbps Upstream8 Mbps Downstream

Video Streaming Video-on-Demand Video Conferencing Interactive Gaming Point-to-Point Data Network on IP

 

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BSNL’s ObjectivesBSNL has undertaken this project with the following objectives: 

To utilize to the maximum BSNL’s existing infrastructure40 Million BSNL Customers on CuLarge scale deployed Fibers in Access & Core network

Deployed DLC Systems on Fiber To increase the footprint across the Country to provide Access

Country Wide To provide Value Added Services (Video, Broadband Data in

addition to Voice) to accelerate development and growth. BSNL has envisioned that the Broadband services rolled as part of the ambitious NIB-II project will be 

Used for high speed Internet connectivity and shall be the primary source of Internet bandwidth

Used for connecting broadband customers to the MPLS VPN through the BRAS.

Used for connecting dial VPN customers to the MPLS VPN through the Narrowband RAS.

 Broadband Services in NIB-II : The Network

 

  

The following are the significant network elements for Broadband: Broadband Remote Access Server (BRAS or BBRAS)

This is the device which acts as the gateway granting customers access to the network. It offers the following services: -Internet Access Broadband AccessVLAN and Gigabit Ethernet Services VPNMulticasting Content Delivery Services

 Aggregation Switch (LAN Switch) The subscriber connections from the DSLAMs are aggregated through this before being passed on to the core router. This again is implemented in two tiers, with a tier–1 switch aggregating traffic from multiple tier-2 switches.

DSL Access Multiplexer (DSLAM)

The DSL Access Multiplexer, popularly known as DSLAM, is employed by the Telecom Companies to code the subscriber line with the broadband data content. Once the ADSL copper line reaches the customer, some customer premises equipment (CPE) has to be employed to separate the voice and data signals.

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 In many cases the Splitter function is combined within the DSL Modem CPE equipment, which is also known sometimes as a ‘Set-top Box’.

Conclusion The introduction of Broadband services is expected to usher in a true era of convergence and introduce a degree of seamlessness between the work and home environment that has never been possible before. Broadband services such as the one proposed by BSL will enable the local telecom companies to retain a foothold in the segment which has seen threats from new entrants like cable TV companies, Power supply carriers, and even gas pipeline companies. And with their traditional expertise in delivering and managing services at the customer’s premises, the telecom companies look slated to outstrip these competitors in this arena as well.

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BROADBAND SERVICES

Services available through Broadband

High speed Internet Access: This is the always-on Internet access service with speed ranging from 2 Mbps to 8 Mbps.

Bandwidth on Demand: This will facilitate customer to change bandwidth as per his / her requirement. For example a customer with 2 Mbps can change to 4 Mbps during the IP TV session.

Multicasting: This is to provide video multicast services for application in distance education, telemedicine etc

Dial VPN Service: This service allows remote users to access their Bandwidth on Demand: This will facilitate customer to change bandwidth as

per his / her requirement. For example a customer with 2 Mbps can change to 4 Mbps during the IP TV session.

Multicasting: This is to provide video multicast services for application in distance education, telemedicine etc

Dial VPN Service: This service allows remote users to access their private network securely over the NIB-II infrastructure.

VPN on Broadband: This facilitates access of VPN using existing Broadband connection.

Video and Audio Conferencing.

Content-based Services: Like Video on Demand, Interactive Gaming, Live and time shifted TV.

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