Project 4

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E-Governance in Bihar A study of BSWAN with

Proposed solutions to the last mile problem By

Yawar Abbas, Indian Institute of Information Technology, Allahabad

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Contents Abstract Disclaimer

Chapter 1

Understanding e-governance 1.1 What is e-governance 1.2 Why e-governance is needed

1.3 Applications of e-governance 1.4 Challenges in front of e-governance in India 1.5 E-Governance in Bihar: from start to what it is today 1.6 Implementing e-governance in Bihar: Agencies and Policies involved

Chapter 2

Understanding State Wide Area Network (SWAN) 2.1 All about networks: From LAN to SWAN 2.2 Implementation of SWAN projects in India: Agencies and Policies 2.3 Implementation Plan of SWAN in India 2.4 Introduction to BSWAN 2.5 Objectives of BSWAN 2.6 Architecture of BSWAN 2.7 The BRAIN DC 2.8 Architecture of SHQ at BRAIN DC 2.9 Connecting SHQ to DHQs 2.10 Linking DHQ to remote offices 2.11 How data travels in BSWAN

Chapter 3

Challenges faced by BSWAN 3.1 Non availability of continuous power 3.2 Single bandwidth provider 3.3 Last mile connectivity 3.4 What is the Last Mile in Telecommunication 3.5 Problems with copper in the last mile 3.6 Bandwidth of a copper link 3.7 Attenuation 3.8 Crosstalk 3.9 Effect of climatic factors 3.10 Underground copper cable cut 3.11 More number of error points 3.12 Cable theft 3.13 Problems of over the ground telephone wires 3.14 Solutions for the last mile: fiber to the home

Chapter 4

Solutions to the Last Mile Problem: WiMAX 4.1 WiMAX: an introduction 4.2 WiMAX and WiFi 4.3 WiMAX: Agencies and policies involved 4.4 WiMAX networks 4.5 WiMAX for the last mile in BSWAN 4.6 Advantages of using WiMAX in local loop

Conclusion

Abstract In the last few years the concept of e-governance, that is, the use of Information and Communication Technologies in government work has gained much ground in India. The projects regarding implementation of e-governance are going on in every Indian state. It is good to see that Bihar which usually lags behinds other states on many fronts is on the fast track to implement e-governance. This report aims at presenting the reader a detailed study on a major e-government initiative in Bihar, the Bihar State Wide Area Network (BSWAN). The main focus of this report is to study the problems associated with the issue of last mile connectivity over copper in BSWAN, which is perhaps the greatest limitation to the performance of BSWAN, along with the factors responsible for them, suggesting alternate means of communication that could be used in the last mile in place of copper. The report starts with Chapter 1 giving the reader a brief overview of e-governance along with the development of e-governance in Bihar. Chapter 2 gives an in depth description of the working of BSWAN. Chapter 3 deals with problems and challenges faced by BSWAN with main focus on the last mile connectivity issues. Subsequent chapter deals with the WiMAX technology as an alternate means of communication that has been suggested to be used in the last mile. Report ends with a brief conclusion.

Disclaimer This report is a result of the study of BSWAN project carried out by myself as part of my summer training during May-June 2009. Though utmost care has been taken to represent facts and figures as correctly as possible, there could be mistakes, for which, I should not be held responsible. References from government documents like draft of IT policy, government of Bihar, RFP for BSWAN, other documents such as white papers/case studies from the websites of the involved companies, technical documents from the electronic hardware vendor companies and information from the internet are taken as and when required. Care has been taken as not to violate any copyrights. I, personally, thank Shri P. C. Chaudhary, BELTRON for permitting me to carry my summer training under BELTRON as well as Shri Sanjay Prakash, Tata Consultancy Services for providing guidance throughout the period of the summer training along with Datacraft team for providing technical details whenever needed. Suggestions and comments, as they are always valuable, are most welcome. I may be contacted on [email protected]/yahoo.co.in Regards, Yawar Abbas B. Tech. 6th semester Department of Electronics and Communication Engineering Indian Institute of Information Technology, Allahabad

Chapter 1 Understanding e-governance 1.1 What is e-Governance In terms of political science, governance in a country literally means the exercise of political, economic and administrative authority in the management of a country’s affairs, so that the citizens can exercise their legal rights and obligations while living in a safe and just environment. E-governance can be thought as the performance of this governance via the electronic medium in order to facilitate an efficient, speedy and transparent process of disseminating information to the public, and other agencies, and for performing government administration activities. e-governance can bring forth new concepts of citizenship, both in terms of citizen needs and responsibilities. Its objective is to engage, enable and empower the citizen. E-Governance can also be thought as the public sector’s use of information and communication technologies with the aim of improving information and service delivery, encouraging citizen participation in the decision-making process and making government more accountable, transparent and effective. It is the use of modern Information and Communication technologies by the government to increase effectiveness, reliability, service delivery and efficiency. An alternative definition to the e-governance may be: E-governance is the application of information & communication technologies to transform the efficiency, effectiveness, transparency and accountability of informational& transactional exchanges with in government, between govt. & govt. agencies of National, State, Municipal & Local levels, citizen & businesses, and to empower citizens through access & use of information 1.2 Why e-governance is needed Through the use of modern information and communication technologies in administrative works, governments can increase the speed and efficiency of the government procedures and transactions. This may lead to a faster, more reliable and better way of communication between various layers of the government. For government offices, which are synonymous with the mismanagement of resources, it could mean better management of resources. It could also help in better management of government records and information in various departments. Due to the computerised storage the e-governance introduces, it would be easier for various departments of the government to utilise each others information in a better and speedy way. For citizens it means the simplifications of complicated and lengthy government procedures. Also if information regarding a government department or a scheme is needed by a citizen he could access it in a more convenient way using the government portals etc. These are just a few causes of the question ‘why e-governance is needed’.

1.3 Applications of e-governance The concept of e-governance i.e. the integration of modern information and communication technologies in public works can be applied to many areas and departments of the present government infrastructure. This may lead to the simplification of procedures for the citizens as well as better utilisation of time and resources and faster dispense of cases for the government departments. As there will be a very efficient way of storing and managing information and records by using electronic means, it will reduce the amount of lengthy paper works which are generally involved in government processes today. Some of departments where this concept can be employed include:

Administration: Various levels of the government could be linked together using ICT. Highest order offices situated in the capital city could be linked to state capital offices which could be linked further downwards to districts headquarters which in turn could be connected to blocks and panchayats. This would enhance the ease as well as speed of passing orders from top to bottom level as well as monitoring the progress in the executions of orders at various levels. It would be a lot easier for the lower level staff to report feedback as well as their grievances to top level. It will also reduce unnecessary paper work which would lead to decrement in government expenditures as well as reduction time in the government procedures to complete.

Department of Road Transport (RTO): Every day many new motor vehicles including two and four wheelers hit the road across the country. Registration of Motor Vehicles in such a large number and collecting road taxes is a very lengthy process where it takes many days for a new vehicle to get a registration number and paper works to be completed only after which it can be driven on the road. Getting a new driving licenses issued as well as renewal of older one is also a tiring process. By computerizing the whole process and adding features like face recognition and biometric sensors it will simplify the current procedure to very large extent.

Health Care: There are many remote villages still in India where a doctor could not be found in a radius of a few kilometers. By establishing a local health center and linking it to various hospitals through faster communication links a better health care can be provided to the people of remote and deeper areas of the country. This could be done by using the concept of Tele-Medicine etc.

Education: Different tires of education system in India like schools, colleges, technical and professional education institutes could be integrated through the use of modern communication links to provide a better education. Use of computers and IT could lead to better means of education through e-learning , distant education, lectures on video conferencing etc. Also using modern communication technology can ensure the reach of education to distant Indian villages and backwards areas with a better ease.

Employment: Employment exchanges could be computerized throughout the country. Online Registration for unemployed, computerization of day to day activities of employment exchange etc as well as interlinking of all the employment exchanges can lead to a better way of executions of government schemes.

Municipality: processes of deposition of various taxes, bills like water supply etc., issue of certificates of birth / death, land records etc could be computerized.

Food and Civil Supply: Issue and renewal of ration cards can be made computerized to save time.

Revenue: The process of registration of property, maintenance of land records, transfer of properties, stamp duty payments, these are a few things that need to be computerized for faster and easy procedures. These are a few areas where electronic means could be applied to make things work fast and easy. 1.4 Challenges in front of e-governance in India Despite very large scale investment and efforts to establish e-government in India the progress has been somewhat slower than what had been expected. This can be attributed to many factors. Some visible challenges in front of the establishment of e-governance in India are: Lack of IT Literacy and awareness regarding benefits of e-governance: There is a general lack of awareness regarding benefits of ICT and e-governance among the common people as well as government staff. The administrative structure in India is not compatible for handling and storing governance information through computerized means. The general tendency among government staff from top officials to lower level staff like clerks is to obtain and process data from the files (in printed or typed format) as and when required and move them table to table to complete procedures rather than using soft copies of the documents and forwarding them by e-mails and other workflow technologies. Underutilization of existing ICT infrastructure: Many departments have adequately good computer facilities but the existing hardware is used only for word processing and printing documents. The hardware is completely or to a large extent not utilised for communication using mails and network sharing as well as making databases and for management related uses. Attitude of Government Departments: The psychology of government servants is quite different from that of private sectors. Where in private sector there is always a welcome for newer technologies, in public sector any attempt to reform the current system is met with resistance from the present employees such as computerization will create job losses. The main reason behind such an opposition to new technology could be credited to the fact that existing workforce would have to upgrade itself to be compatible to new technology which would involve a great deal of efforts from there side as well.

Lack of infrastructure to support e-governance: In e-governance modern electronic equipments as well as fast communication links are needed. Due to the fact that India is a very large country, purchase of sufficient hardware and software needed would incur a very large cost. Also, availability of reliable and secure communication links in the remote locations a serious concern. Getting uninterrupted electricity in interior locations to run the electronic infrastructure is also a great difficulty. All these factors make the progress of egovernance a bit difficult. Lack of skilled manpower: If e-governance is taken to the very root level that is to all the villages and panchayats, a very large number of people trained in the field of IT would be needed. Recruiting, training, employing and managing such a large workforce is perhaps the greatest challenge in the path of the progress of e-governance in India. These are only a few challenges besides many more. But by proper management and administration from the government side they could be overcome and India can progress on the path to achieve e-governance in near future. 1.5 E-Governance in Bihar: from start to what it is today Almost three years back, Bihar was lagging far behind in terms of the implementation of IT in government affairs. It was among the least achiever states. There was no separate Department of IT in government of Bihar. Bihar government decided to set up a separate IT department in April 2007. Till then IT department was under the ministry of science and technology. Also a full time IT secretary was appointed in April 2008. Mr. Alok V Chaturvedi became the first IT secretary of Bihar and has spearheaded the IT initiatives of the Government of Bihar most efficiently. The projects that have made some considerable progress in terms of implementation are the treasury management information system, and the VAT management information system. These are supported by the state data center Bihar Revenue Administration Intranet Data Center (BRAIN DC), already set up in Technology Bhawan, Bailey Road, Patna-1. The BRAIN DC is providing many functionalities like serving as the Central Repository of the State, Secure Data Storage, Online Delivery of Services, Citizen information/Services Portal, State Intranet Portal, Disaster Recovery, Remote Management and Service Integration. It is fully operational till date. The implementation of a state wide area network connecting state headquarter to all the district headquarters and in turn connecting them to all the blocks under the districts is also in the final stage of implementation. Bihar State Wide Area Network (BSWAN) is currently providing 2 Mbps (initially) vertical connectivity across the State upto Block level right from the State Headquarter. The SHQ is located in Patna in conjunction with the State Data Center, the BRAIN DC. At SHQ and all the DHQs, STM1 facility is provided so as to scale up and meet the future bandwidth requirements. Bihar is one of the states where implementation of SWAN is in an advanced stage. Fig 1.7 tells the story upto June 2009. Till June 30th, 2009 309 BHQs of all 37 DHQs have gone live on the network.

Another initiative that could be appreciated is a 50:50 joint venture called Bihar eGovernance Services and Technology (BeST), with Bihar State Electronics Developement Corporation (BELTRON) and Infrastructure Lease and Finance Services (ILF&S) as participants. Beltron and ILF&S are official consultants for the Government of Bihar, and have saved a lot of time and effort for the government in terms of finding consultants for projects. They are a single interface for preparation of Requests for Proposal (RFPs) and tendering. This, according to government of Bihar, will help the government attract good quality hardware and software vendors. Yet another project which deserves appreciation is the SecLAN project. Department of Information Technology has initiated Secretariat Local Area Network (SecLAN) project to connect all Government offices in and around the State Secretariat though Gigabit fibre connectivity backbone. This would help in easy communication within the offices, information sharing, file movement and would result in better efficiency, effective coordination and reduced time cycle. Linkages between SecLAN, BRAIN DC and BSWAN would provide e-mail, voice, data and video communication facility to the Chief Minister, Other Ministers, Chief Secretary and officials. In Bihar this project is in advance stage of implementation.

Fig 1.7 status of swan projects in states

Another project with advanced level implementation is the Common Service Center (CSC) named Vasudha: Government of Bihar has already taken action to create a network of Common Services Centres (CSCs), christened Vasudha, in all 8,463 panchayats of the State as outlets for various services. Vasudha Kendras have been designed as ICT-enabled centers having a PC along with basic support equipment like Printer, Scanner, UPS, with Wireless Connectivity as the backbone and additional equipment for edutainment, telemedicine, entertainment etc. Bihar stands among the top states in terms of roll out of number of CSCs. Fig 1.8 gives the status of CSC roll outs across India upto May 2009.

Fig 1.8a CSC implementation across India

Fig 1.8b Ranking of states in terms of CSC rollouts

1.6 Implementing e-governance in Bihar: Agencies and policies involved

IT VISION OF BIHAR “Our vision is that by the end of 2012, Bihar becomes one of the top five eGoverned, IT-enabled, e-Literate States in the Country and is regarded as a preferred destination for IT businesses and is a major supplier of skilled IT manpower.” For details regarding IT policy of Government of Bihar, a draft of IT policy has been made which is available on: http://gov.bih.nic.in/Documents/Draft_IT_Policy_2008.pdf.

Department of IT, Government of Bihar is the prime agency in BSWAN project. BSWAN project is underway with BELTRON as nodal agency while Tata Consultancy Services (TCS) chosen as operator of BSWAN. ILF&s is consultant in this project. Telecommunication links are provided by Bharat Sanchar Nigam Limited. The project is on a Build Own Operate Transfer (BOOT) basis under Public Private Partnership (PPP). BRAIN DC is operated by TCS with BELTRON as nodal agency. SecLAN has been implemented by Spanco Ltd. BeST is a 50:50 JV between ILF&S and BELTRON. CSC is a DIT, GoI initiative with ILF&S acting as consultant. Next chapter deals with an overview of the evolution of BSWAN and the working of BSWAN in details.

Chapter 2 Understanding Bihar State Wide Area Network (BSWAN) 2.1 All about networks: LAN to SWAN Communication Network - The term ‘Communication Network’ today, refers to a group of telecommunication systems and computers connected to each other by some communication channel to share the resources. There can be many types of Communication Network:1) Local Area Network (LAN) – It connects host computers and network devices over a relatively short distance like in a single building or campus. LANs are typically owned, controlled and managed by a single person and organization. It can be wired or wireless. Computers need Ethernet ports to connect to the LAN. 2) Metropolitan Area Network (MAN) - A MAN is a network which is designed to cover a relatively large geographical area extend over an entire city. It may be a single network, or it may be a collection of a number of independent LANs integrated into a larger network. 3) Wide Area Network (WAN) – A WAN is a network designed to provides very long distance transmission of data, voice, image and video information over large geographical areas that may comprise a country, continent, or even the whole world. Wide Area Network is a collection of networks spread over a geographical area which communicate with each other by using suitable network devices. State Wide Area Network (SWAN) is a special case of WAN covering a whole state, incorporating many networks for providing data, voice and video services throughout the state. It is mainly used by the government agencies in order to implement e-governance in the state. Use of a typical State Wide Area Network (SWAN) maybe in providing efficient & reliable communication network to improve information flow among various levels and offices with reduced communication gaps and improved quality and speedy decision making for faster and better implementation of government schemes. 2.2 Implementation of SWAN projects in India: Agencies and Policies Govt. of India, Department of Information Technology (DIT) is the prime agency for the implementation of SWAN in states of India. The Government of India has planned a national level initiative- National e-Governance Plan, (NeGP) for increased transparency, efficiency and effectiveness for delivery of citizen services. Setting up NeGP was the first step towards adapting e-governance in India. An important component of the NeGP is SWAN which can be identified as an element of core infrastructure for supporting e- Governance initiatives.

Under NeGP SWAN policy it is proposed to connect state capital (SHQ) with all the Districts Head Quarter (DHQ) and subsequently all the DHQ to be connected with Sub-division Head Quarter/Blocks (SDHQ/Block). SWAN is no doubt the backbone for the implementation of electronic government projects as it provides necessary connectivity needed. For GoI, SWAN is one of the Mission Mode projects. GoI planes a total expenditure under NeGP for SWAN in all the states over Rs 3000 Cr to connect state capital (SHQ) with all the Districts Head Quarter (DHQ) and subsequently all the DHQ to be connected with Sub-division Head Quarter / Blocks (SDHQ/Block). 2.3 Implementation Plan of SWAN in India State would need to establish the SWAN using either of the two options provided by DIT, GOI: Option I: State has to identify a suitable PPP model (BOO, BOOT etc.), select an appropriate agency through a suitable competitive process for outsourcing establishment, operation and maintenance of the Network. It can also appoint a consultant. Option II: Designate National Informatics Center (NIC) as the prime implementation agency for the SWAN for establishment, operation and maintenance of the network as an integral part of NICNET, with an appropriate end-to-end Service Level Agreement (SLA). Department of IT, GoI supports the costs, funding to state government w.r.t. different options in order to build a SWAN in the state. DIT will support the entire cost of establishment, operation and maintenance of the SWAN for a period of five years (except recurring charges of Bandwidth) to state Govt / NIC on 100% grant basis. Cost of terminal equipment at each Point of Presence (PoP) with one PoP at each location (without horizontal connectivity) i.e. SHQ/DHQs/SDHQs/BHQs would also be covered by the SWAN. Cost of consultancy (only for option I), cost of third party monitoring (option I) / cost of third party auditors (option II) are also covered under this policy. 2.4 Introduction to the BSWAN In Bihar SWAN is constructed under option I with BOOT model. BSWAN is one of the largest SWAN in the country. In BSWAN there are 1 SHQ, 37 DHQs, 496 BHQ POPs. The BSWAN project was sanctioned by GoI 31.10.06. Letter Of Intrest was issued on 14.08.07. The target completion date was set as 30.09.08. BELTRON is the nodal agency for the BSWAN project. TCS was selected as BSWAN operator while BSNL as the bandwidth provider. ILF&S is the consultant agency for the project. Datacraft was selected as link commissioning and monitoring agency to coordinate between BSNL and TCS. It aimed to connect in Phase-1- 111 sites :- 37 SHQ+DHQs)+74 BHQs and in Phase-2- rest 422BHQs 2.5 Objectives of BSWAN 

The Bihar state Wide area Network (BSWAN) is implemented for the purpose of:

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Connecting Govt. agencies/ departments/ offices at SHQ with all DHQs and subsequently to all the SDHQs/Blocks in a 24x7 quality network, extendable for Public to Government interaction

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Providing connectivity across the state through one network and re-engineering of various departments and government services to ensure easy information flow

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Having one single network to deploy the e-Gov application for various activities

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Establishing a network that functions as IT gateway for seamless, effortless & instantaneous information flow

Thus BSWAN is designed and implemented to be a converged network providing services: Data, Voice and Video - SHQ and DHQ, Data and Voice- SDHQ and BHQ and Internet throughout the state for Government of Bihar though till date, internet facility is provided only for users of SecLAN in SHQ . There are many facilities provided by BSWAN such as it provides seamless connectivity among Government departments / directorates as well as among the various offices of each department / directorate all over the state of Bihar. Various government applications will use this network for transfer critical data from State Head Quarters (SHQ) to District Headquarters (DHQ) and subsequently to the Block Head Quarter (BHQ). It serves as an efficient communication mode for different tires of the state government. The implementation of BSWAN also facilitates the implementation of Bihar Revenue Administration Intranet (BRAIN) for on line management of VAT / treasury. 2.6 Architecture of BSWAN: BSWAN connects state headquarter located at Patna to all the district headquarters which are in turn, connected to all the blocks. Offices like VAT, treasuries, jails etc in each district are connected to DHQ through horizontal links. Fig 2.5 shows the hierarchy.

Fig 2.5: Hierarchy of connectivity in BSWAN

Different tires of the connectivity under BSWAN are:

In BSWAN different entities are present as: State Head quarters (SHQ) - 1 Nos. It constitutes tire 1. State capital Patna acts as SHQ which is located in BRAIN DC, Technology Bhawan, Bailey Road, Patna-1. It is integrated to Secretariat LAN with all 7 Secretariat buildings. District Head quarters (DHQ) - 37 Nos. They constitute tire 2. DM’s office is operating as Centre hub of DHQ with multiuser support. Connectivity of remote offices like VAT, treasuries, jails etc is through horizontal links. Connectivity to all the blocks under each district is through vertical links. Blocks Head Quarters - 495 Nos. They are at bottom layer that is tire 3. BDO office acts as center at block level. 2.7 The BRAIN DC The SHQ of BSWAN is located in Technology Bhawan, Patna. It is present inside the BRAIN DC. Besides hosting the SHQ, BRAIN DC has many other functionalities such as: Comprehensive Treasury Management Information System (CTMIS): It provides a long term solution for carrying out treasury functions of Government of Bihar (GoB) and provides consolidated and consistent information about the expenditure and revenues across all the treasuries in the state. The system is also designed to include the non treasury transactions of GoB to cover its overall income and expenses. Value Added Tax Information System: Government of Bihar has implemented Value Added Tax (VAT) across Bihar with effect from April 1, 2005. Towards this, Finance (Commercial

Taxes) Department, Government of Bihar wishes to improve the existing state of computerization. This initiative aims to achieve the following objectives:  Conversion to an online transaction processing system from a batch data entry mode of operation.  Improved and Increased Tax Revenue Base and Collections  Improved Services to Citizens by making services available through internet  Transparency, Accountability and Efficiency  Improved Internal Functioning of Finance (Commercial Taxes) Department BiharOnline : It is the digital gateway for the GoB to offer multiple services, through a single window, to its citizens. The portal will redefine governance and the government citizen interface in Bihar. BiharOnline will be comprehensive in scope and offer a variety of informative, interactive and payment services to the citizens and businesses across the state. It will be easily accessible through multiple delivery channels (SDPs, cyber cafes, government counters), homes and offices, anytime, anywhere, to deliver services at citizens' homes. Integrated Workflow and Document Management System (iWDMS): is a multilingual product for automating the functions at all levels of the administrative hierarchy of any governmental department. iWDMS provides Document Management, Workflow Management, Collaborative Environment and Knowledge Management in an integrated fashion and delivers an electronic workplace to the end user in the department concerned. By implementing iWDMS, Government of Bihar will achieve the following objectives:  Ensure effective, efficient & transparent administration and to create an automated Office Management System to enhance productivity and enable prioritisation of work.  Use IT as an enabler to help in daily work design an efficient workplace  Enable Policy Based Processing by providing a mechanism for information and experience sharing  Helping in effective collaboration between various personnel.

Fig 2.6 Architecture of BRAIN DC

2.8 Architecture of SHQ at BRAIN DC In the heart of the SHQ at BRAIN DC, there is a core switch by NORTEL. SecLAN and other application servers situated inside the BRAIN DC are connected to this switch. For internet connectivity SHQ uses the internet service provided by BSNL. An internet router is connected to the core switch though firewall and network proxy server and through this setup the BSWAN gets connected to the internet. For redundancy, there is another Internet Service Provider (ISP), the RailTel. It has its own internet router which is connected to the core switch through the same way. Users of SecLAN can connect to the BSWAN and the internet through this core switch as well as facilities at the BRAIN DC can be used by external users (such as accessing web portals of Bihar government like BiharOnline or using e-mail facilities provided) as well as users in BSWAN through this core switch. The core switch is connected to the SHQ core router which is Juniper JM 120. The function of this router is to route the data traffic going to various DHQs through the proper and the shortest possible path. It uses OSPF routing protocol. The SHQ core router has in built STM 1 functionality and it supports OFC connection through STM 1 port. It is connected to BSNL main telephone exchange at Budh Marg, Patna through an underground Optical Fiber Cable (OFC).

Fig 2.7 Architecture of SHQ of BSWAN

2.9 Connecting SHQ to DHQs In STM 1 link there are 63 E1 links of 2 Mbps each in electrical domain which are multiplexed to give an optical link of 155.3 Mbps. In BSWAN SHQ core router these 2 Mbps links are used to connect different DHQs. Traffic going towards different DHQs is multiplexed to give a single link of STM 1 which goes through OFC to the BSNL main exchange. This OFC terminates at the local transmission room at BSNL main exchange which is the Optical Fiber Center at the 1st floor of the exchange building at Budh Marg, Patna. There a dedicated STM 1 system is commissioned for the use of BSWAN. Here the 63 links are demultiplexed physically and 63 lines in electrical domain of 2 Mbps each are extracted. At the SHQ core router there is no physical multiplexing/ demultiplexing of 63 lines into STM 1 but the same functionality is provided logically that is by using software. Of these 63 lines of 2 Mbps each, 37 lines are used to connect 37 DHQs. It has been defined while designing the BSWAN that of these 37 lines, which numbered line goes where. Electrical lines of 2 Mbps from the STM 1 module are terminated at the Digital Distribution Frame (DDF) which is used to distribute these electrical lines inside the telephone exchange building. Through DDF these lines go to the Long Distance Transmission Room which is located at the 2nd floor of the same building. For long distance transmission, BSNL has a very large scale Optical Fiber Network throughout the country and there are telecom routes defined to connect various cities. High capacity OFC lines pass through these routes which interconnect different cities. In the Long Distance Transmission Room, each line going to a different DHQ is passed to a telecom route serving to connect Patna to that district. This line is then multiplexed with other lines going in the same direction. Here multiplexing is of a very high order. It may be STM 64 or DWDM or even higher. Through the BSNL OFC network this highly multiplexed line which is of a very high bitrate (often in Gbps) travels to the destination district town. Thus the 2Mbps line directed to a DHQ from the SHQ reaches that district using the BSNL cloud. At the main telephone exchange in that district the line of high bitrate coming from the state capital is demultiplexed and the 2Mbps line coming from the SHQ of BSWAN is extracted. There is a dedicated STM 1module provided at each DHQ town exchange. The 2 Mbps line coming from the SHQ is fed into one of the 63 channels of this STM 1 module. Other channels of this STM 1 module are used for the connectivity of DHQ with remote offices like VAT, treasury, Jail, Court etc and all the BHQs. The 63 lines entering this STM1 module are multiplexed to give a STM 1 line which goes to the DHQ through underground OFC. DHQ is usually located at the DM’s office in district headquarter towns. In DHQ there is a core router with STM-1 functionality and the OFC from BSNL exchange terminates there. This router is responsible for the vertical connectivity of DHQ with BHQs as well as horizontal connectivity of DHQ with remote offices like VAT, Treasury etc. This router is connected to a network switch through which users on a local LAN can connect to the BSWAN. Fig 2.8a shows the connectivity from SHQ to BSNL main exchange, Patna while fig 2.8b shows the rest of the connectivity upto DHQ.

Fig 2.8a: connecting SHQ to DHQ

Fig 2.8b: connecting SHQ to DHQ

Througout this report communication links provided by BSNL refer to bidirectional links i.e. they are used for transmission as well as reception of data. There are always two separate wires whether talked about optical or electrical links, one to carry traffic in each direction. If process of sending data in one direction is given, one can assume the reverse way out with processes interchanged i.e. demux in place of mux and likewise and optical to electrical in place of electrical and likewise. 2.10 Linking DHQ to remote offices The connectivity of DHQ with remote offices is again provided by BSNL links but this time there could be a combination of optical and electrical links over copper media. The links to various remote offices and the BHQs are taken from the channels of STM 1 used at local BSNL exchange at district headquarter town. One channel is reserved for communication with SHQ while the rest can be assigned to communicate with remote offices and BHQs. The core router at the DHQ is configured to distribute the traffic going towards SHQ and remote office at different numbered channels of the STM 1 system. Suppose a

remote office or BHQ is given connectivity from the DHQ at a certain numbered channel of this STM 1 system. The router at the DHQ will logically switch the traffic going to that remote office or BHQ (which is a 2Mbps link) to the channel number reserved for that remote office or BHQ. This traffic is then multiplexed (again logically ) to travel through the STM 1 link to the BSNL exchange of that town upto the STM 1 module reserved for the use of DHQ. There this link is demultiplexed and the link to that remote office or BHQ is obtained at the same channel number of the STM 1 module in the form of a 2 Mbps electrical link which is E1. Now this link has to be connected to the remote office or BHQ through BSNL network. At this time, in India, the optical fiber network of BSNL has become very wide spread and has reached almost everywhere including very remote rural areas. Therefore, without loss of generality it can be assumed that there exists a telephone exchange nearest to the remote office or BHQ concerned upto which BSNL’s optical fiber network has reached. Also it can be assumed that all such telephone exchanges are connected to telephone exchange in the district headquarter town, where STM 1 module for the use of DHQ is installed, through BSNL’s OFC telecom routes. Upto this nearest exchange we can have send or receive data through optical fiber. Using OFC for long distance transmission has its own benefits like very high bandwidth, very low bit error rate, high reliability and easy maintenance.

Fig 2.9: connecting DHQ to BHQ

With these assumptions, such a telephone exchange nearest to the remote office or BHQ concerned is identified. Once this is done, the E1 Link from the DHQ extracted from STM-1 system in the BSNL exchange is diverted to the route serving the exchange nearest to the

remote office or BHQ concerned. This is achieved by multiplexing it with other lines going to the same direction and then putting the traffic to the route concerned. Through this route the traffic reaches the destination i. e. to the exchange nearest to the remote office or BHQ concerned. There it is demultiplexed and then the link of 2 mbps from the DHQ is extracted in the form of electrical E1 link. Next step is to connect this link to the remote office or BHQ. Now, there is no more optical fiber link to carry the data to the destination. So, the desired connection can be made using the concept of Digital Subscriber Line (DSL) also known as leased line. It is a copper link supporting 2Mbps bitrate and connecting Consumer Premise Equipment (CPE) to the nearest exchange. The E1 link from the DHQ is fed to a modem present inside the exchange and other end of the modem is connected to the Main Distribution Frame of the exchange. From there it travels through undergroung copper cabling and overground telephones wire over the poles and reaches the remote office or BHQ concerned in the form of a copper pair. There it is fed to a modem and other end of the modem is connected to a router at the office. From the router, a switch is connected and through this switch and router user PCs at the office connect to BSWAN. At all levels of BSWAN, IP phones have been provided for voice communication. They all are connected to PBXs installed at the respected levels i.e. at SHQ, DHQ and BHQ and the PBX equipment is connected to the router through the network switch. Facility for video conferencing is also provided in BSWAN and VC equipments are also present at all levels. They are also connected to BSWAN through network switch and routers. An AAA (authentication, authorization, accounting) server is also installed at the SHQ which is connected to the core switch there. A beautiful picture from TCS, operator of BSWAN gives the complete overview of BSWAN.

2.11 How data travels in BSWAN Suppose a data packet is generated by a user in a remote block of district A which has to be modified by a SecLAN user and forwarded to a user in remote office X of district B. This section gives a complete path of how the data will travel for this application. The data packet generated by a user PC at a remote block will go through the switch and router installed there and from there to the nearest exchange using DSL link connecting the BHQ to the nearest exchange. From there it will travel through BSNL OFC network to the exchange located in DHQ town where STM 1 module for the use of DHQ is installed. There it will be fed at the channel reserved for the connectivity of DHQ with that remote BHQ. It will be multiplexed and reaches the DHQ router through the underground OFC STM 1 link. There the router logically extracts this packet and identifies the destination which is the SHQ. It switches it over one of the STM 1 channels reserved to communicate with SHQ. It again gets multiplexed and travels through the OFC STM 1 link back to the exchange in DHQ town and from there it reaches the Patna Main Exchange through BSNL OFC network. From there it is fed to the channel of STM 1 module used for BSWAN that is located in Patna Main exchange, reserved to link that DHQ with SHQ and reaches the SHQ router. The SHQ router forwards the packet to SecLAN router which in turn makes it to reach the destination concerned that is the concerned SecLAN user. The user modifies the data packet and forwards it to destination that is the office X of district B. The packet then reaches back to the SecLAN router which forwards it to the SHQ router. SHQ router identifies the destination and switches it to the channel of STM 1 used for connectivity between SHQ and the corresponding DHQ in district B. It travels through the STM 1 link to Patna Main Exchange from where it is sent to the district B exchange through the BSNL cloud. It is received there and is forwarded to the DHQ router through STM 1 module in the exchange for the use of DHQ. DHQ router identifies the destination and switches it over the channel of STM 1 reserved to communicate with the remote office X concerned. It travels back to the exchange at DHQ town which has the above said STM 1 module used for DHQ. The data packet is then transmitted to the exchange nearest to the office X through OFC network and from there it travels through copper media to the router at the office which forwards it to the user concerned. By a little intuition paths concerned in all other applications can be identified. It is also possible that BSNL connects a remote office or BHQ to the nearest exchange where the OFC network has reached, through one or more intermediate exchanges using copper media. Underground copper cabling can be used to connect the nearest exchange which is on the OFC network with the exchange nearest to the remote office or BHQ through the intermediate exchanges and the concerned office can be linked to this nearest exchange via leased line over copper medium. This was all about the working of BSWAN. The reader can refer to websites of BELTRON, TCS, BSNL for more literature on the subject. The next table shows the list of equipments present at each level.

SHQ

DHQ

BHQ

Core Router

Juniper JM 120

Juniper JM 110

Juniper JM 4350

Internet Router

----

EPBAX

Juniper JM 4350 ---for BSNL. RailTel has it’s own router. Nortel 8005 (core Nortel 5520 switch) Nortel Nortel

VCE

Polycom

Polycom

Polycom

AAA server

Juniper steelbelt

---

---

Switch

Nortel 2550 Nortel

This was all about the working of BSWAN. The reader can refer to websites of BELTRON, TCS, BSNL for more literature on the subject. In the next chapter some of the challenges the BSWAN faces today, like non availability of continuous power, dependence on the services of a single bandwidth provider i.e. BSNL, last mile issues where connectivity over copper is involved etc. are discussed. Using copper media to connect a subscriber to the nearest telephone exchange has several problems often referred to as the last mile problem. As the main focus of this report is to study the problems associated with the last mile connectivity over copper and suggest a viable solution, this topic will be discussed in details giving a brief discussion of the other problems faced.

Chapter 3 Challenges faced by BSWAN There are many challenges BSWAN faces today. Some of them are discussed one by one. 3.1 Non availability of continuous power The state of electricity in rural areas of Bihar is not good. One cannot expect power to be available continuously over longer spans of time. Also at the lowermost level of connectivity in BSWAN are the BHQs which are usually in far located rural areas of a district. In many such places there is no electricity at all i.e. electricity has not reached there. Where there it has reached also, it cannot be expected to be available for all the time during working hours. Therefore one has to rely on alternative sources as well. The most commonly used source is the diesel generator (DG). It promises adequate power and its installation costs are also not very high but it has its own problems like it runs on bio fuel (diesel) which is costly as well as using it is not environment friendly as it contributes to pollution a s well as high noise level in the vicinity. Solar power can be used as another alternative which promises clean continuous power but one time installation costs of equipments are too high which make it less favoured. 3.2 Single bandwidth provider As on today, BSNL is the only bandwidth provider in BSWAN. So if something happens to the BSNL network and it goes down, there is no backup present. Also BSWAN has to compromise with somewhat not very efficient services of BSNL staff. Solution to this problem can be using the services of another network provider for backup. At present, other companies like RailTel, GAIL etc have developed their own OFC networks and their services can be used when require. 3.3 Last mile connectivity This is the biggest challenge to the performance of BSWAN. As this is the main focus of the report it is discussed in detail. 3.4 What is the Last Mile in Telecommunication The connectivity of a subscriber premise equipment to the nearest telephone exchange is often referred to as the last mile connectivity. It is the final step of the link to the subscriber from the service provider side which connects a subscriber to the nearest telephone exchange and through this nearest telephone exchange the subscriber gets connected to the world using the telecommunication network of the service provider. This is also known as the local loop. In wireless communication like mobile telephony, it is the portion of network between the customer premise and the network operator's (usually nearest) point of presence such as a Base Transceiver Station (BTS).

In a leased line connection for data communication, the last mile connectivity is usually provided by copper media. The line from the exchange passes through modem and goes to the MDF of the telephone exchange. From there it is put over underground copper cables. It travels all the way through them and partially on copper wires over the telephone poles and finally reaches to the subscriber home in the form of a dead copper pair. Copper pairs are still the main transmission media in the local loop. One of the main advantages of copper is that today, more than one hundred years after it was first used, it is still available for almost any potential customer in any developed or developing country. And despite of numerous advantages of OFC, copper cables are still being rolled out today. Digital Subscriber Loop (DSL) or leased line technologies were originally designed for digital transmission over the existing telephone copper pairs. This combined costeffectiveness and acceptable performance. However, copper is now reaching its limits, and new access technologies based on optical fibre are arising. Telecommunications companies worldwide are still transmitting data over copper wires, using different variations of DSL, and there are still more than 160 million subscribers around the world today. In the BSWAN the last mile connectivity is almost completely on the copper media. Though OFC network of BSNL is used wherever possible, most remote offices are connected with copper in the last mile. The reason behind this is that laying optical fiber cables is a very expensive process and it is very difficult and expensive to take optical fiber cabling to every household or office separately. Therefore, for last mile connectivity the existing copper infrastructure must be used. 3.5 Problems with copper in the last mile In India, the use of copper in the last mile is most common for telephone connections that carry voice. Same concept is also used for data communication over telephone lines and most of the leased line connections use copper for the local loop. Despite being very popular, this concept suffers from a number of problems. Due to these problems the communication links that employ copper in local loop suffer from serious degradation in service. A common sight in India is that landline telephone connections which mostly rely on the use of copper for this type of connectivity very often go dead by one or more reasons or they offer a very bad quality of voice reception even when they are alive. The effects are more pronounced when the landlines are used for data communication in leased line connection and despite paying a large amount for leased line connectivity the subscriber is not satisfied with the quality of the service offered from the service provider. Next, are discussed some common problems with copper links in the last mile. 3.6 Bandwidth of a copper link Last mile connectivity over copper is primarily designed to carry voice traffic. When it is used in data communication, there is a limit on the maximum bitrate through copper pairs. Usually it is 2Mbps in the form of electric pulses. When the copper media is used in last mile

it is very difficult to cross this limit. With advanced DSL variants like VDSL , it is possible to increase the bitrate over copper pairs many folds but as the distance from the exchange to the subscriber increases, the bitrate falls. 3.7 Attenuation Copper is a metal with a fixed value of specific resistivity. Voice or data signals travel on the copper wires in the form of electrical signals. As the distance of transmission increases, due to the resistance offered by copper, electrical signals fade i. e. They become weaker. This is called attenuation. For the receiver to identify the incoming signals correctly they have to be passed through a repeater which is an amplifier and boosts the signals to a higher voltage level. In digital communication the shapes of electric pulses representing binary signals may get damaged due to attenuation or they may elongate and distort. Due to this adjacent pulses may overlap with one another and thus making the resultant signal difficult for the receiver to identify correctly between logical high and low levels. The net result is a high bit error rate which often results in the wrong interpretation of data or even data loss. 3.8 Crosstalk In underground copper cables or wires over telephone poles, very often, different pairs containing traffic from different end users are in close proximity of each other. Due to the electrical nature of signals contained by them they affect each others data. A signal that is being transmitted over a copper pair may potentially damage the signals travelling in the neighbouring pairs. This is called crosstalk. This effect also degrades the quality of services offered through copper media. 3.9 Effect of climatic factors Bihar has extreme type of climate. Summers are very hot while winters are spine chilling. Copper is a metal with a resistivity which is dependent on temperature. Due to extreme type of climate the resistivity of copper lines deviates much from the value assumed while designing the copper link. Due to this, attenuation levels are different from what are expected and this results in an overall deviation in performance from the expected level. This leads to degraded performance of copper links during extreme heat or cold including data loss. Similarly during rains water may enter inside the protective covering of the copper pair exposed to the environment. This disturbs the data flow over the pair. Water from the drainages and underground water may also enter inside the underground copper cables. If it reaches to the individual pairs inside the cable then there may be problem with the dataflow. 3.10 Underground copper cable cut Due to widening of roads, laying of water supply pipelines, making underground drainage system or other activities involving digging the earth along the sideways of roads there is a potential threat of the underground telecom cables getting cut. It is a very common sight to

have many telephones of a locality going dead simultaneously due to underground cable cut. If a fiber optic cable is cut, there are machines which can find out the exact location where the cut has occurred. They send a light pulse along the cable which is propagated back to the source after getting reflected from the end that has been cut. Recording the time interval involved in the round trip travel of light pulse and knowing the speed of light, exact location of the cut can be found out. But, unfortunately, if a copper cable is cut there is no such a convenient way to find out the location of the cut. BSNL staff has to travel along the path suspected to have the cut checking for cut at different places. This makes the detection of cut very tiring and time taking process. If the location of the cut is found out then also it is very difficult and time consuming to repair and restore a high capacity copper cable than restoring a fiber optic cable which is relatively easy and very fast process. It typically takes days to restore a high capacity underground copper cable. Improperly joint copper cables have their own problems leading to flapping of the link that is the link going up and down time repeatedly within a short interval of time, typically a few minutes. If the protective coating of a pair in underground cabling is broken and if, through this, copper can get an earthing, it may lead to a leakage current which will result in loss of data as well as it can damage electronic equipments on both sides. 3.11 More number of error points A typical copper leased line link from the subscriber, carrying voice and data in electrical form, first passes through the modem present in the subscriber home. Then it goes to the distribution box of the telecom company usually present along the roads on small distances or on the chowk, chaurahas, over the telephone wires on the poles. From there the link travels on the underground copper cables to the MDF of nearest telephone exchange where the copper cabling terminates. From MDF the link passes through a modem present inside the exchange and travels to the transmission room where it is converted from electrical into optical domain. From there it uses the OFC network to travel further. Thus a number of different connection points or interfaces are involved in between the subscriber home and the link getting converted into optical domain at the nearest exchange. Each interface leads to an error point. Any improper connection or complete disconnection at any point or malfunctioning of any of the involved equipments like modem etc may lead to severe obstruction in the link like data loss and even sometimes the link going completely down. 3.12 Cable theft Many times the underground copper cable or the telephone wires over the poles get theft. This results in all the links relying on the portion of cable that has been theft going down. 3.13 Problems of over the ground telephone wires In many cases they form the last step of the last mile that is they take the link to the subscriber home finally. They are hanging wires on the poles and are exposed to the environment. It is not unusual for them and the poles carrying them to get broken by factors

like getting hit by a tall vehicle or getting broken in a storm or rainfall. If this happens the links depending on the broken wire or pole will go down. Restoring them in such events takes a long time and during this time the links remain dead. Multiple joints in such copper pairs to restore the broken pairs often lead to degraded performance and flapping. If rubber or plastic coating protecting the copper wire is broken and the exposed copper can get in contact with electricity wires then it may lead to serious hazards. Some of the problems associated with copper in the last mile are discussed above. Any one or a combination of more than one of them may dominate on a given time. Results may range from lower than expected level of performances to the link going completely dead. TCS, the BSWAN operator, has reported that, on an average OFC links are up for the 99% of time, while copper links in the last mile are, at most, up only for 74% of time. Though BSWAN is being operated successfully even on this statistics, discussions are going on to improve the overall performance of BSWAN and specially to improve the connectivity in the last mile. 3.14 Solutions for the last mile: fiber to the home Taking optical fiber cable to the destination office is the best possible solution to the last mile problem. For this the existing OFC network has to be extended to the desired office through a leased line connection over fiber. Using an optical fiber supporting modem at the subscriber end in place of the normal DSL modem can guarantee the same (even better) performance as in the copper case with same ease without replacing any other equipment. Using OFC right upto subscriber home promises the best performance. Using OFC is reliable because it is a wired connection, OFC can support higher bitrates than copper, using it is more secure than copper, there are no problems like crosstalk, attenuation etc. and there is possibly no chance of flapping also. But laying OFC network is a very costly affair. It involves huge expenses to extend the existing OFC network to every street and ever village. Digging land and laying OFC through other people’s property and government assets like roads involves a lot of permissioning ad licencing. Even if the optical fiber cable is able to reach the destination office there are threats like cable cut or theft still present. Therefore going wireless in the last mile is a better solution. Though it does not support bitrates as high as fiber and it is also not as reliable as a wired connection, it still gives the good solutions to many last mile problems and most important than all, it offers the best trade off between reliability, quality of service and cost. In the next chapter wireless option WiMAX is discussed in detail with a little bit WiFi also involved.

Chapter 4 Solutions for the last mile: WiMAX 4.1 WiMAX: an introduction The term WiMAX stands for the Worldwide Interoperability for Microwave Access (WiMAX). WiMAX is a IEEE standard-based wireless technology that provides high throughput wireless communication over long distance. WiMAX can be used for a number of applications, including “last mile” connections in leased lines, providing wireless broadband connections, hotspots and high-speed connectivity for business customers. It provides wireless metropolitan area network (MAN) connectivity at speeds up to 70 Mbps and the WiMAX base station, in today’s technology on the average can cover an area between 5 to 10 km. Today WiMAX is an emerging technology for providing high speed wireless access to subscribers. It offers both fixed and mobile broadband wireless Internet access. It offers very high data rates, high reliability, good efficiency at comparatively low cost. WiMAX enjoys strong industry support and standardization. Because of its low cost, WiMAX can be used to provide wireless last mile access to users in suburban and rural areas where the limits of underlying cables have saturated or which are too far flung to be reached by a wired connection and thus it is capable to bridge the digital divide between the users in rural and urban areas. WiMAX is considered today the most interesting opportunity in the field of wireless communication, and it is expected to be able to provide radio coverage distances of almost 50 kilometers and data throughput up to 70 Mbps in coming years. Right now it is perhaps the best way available to complete the wired network architectures, ensuring a flexible and cheap solution for the last-mile. WiMAX is expected to have an explosive growth, as well as the WiFi, but compared with the Wi-Fi WiMAX covers greater areas, measured in many square kilometers, and supports links even not in line of sight. For these reasons WiMAX is a MAN, highlighting that “metropolitan” is referred to the extension of the areas and not to the density of population. WiMAX supports different types of broadband wireless connections: metropolitan networks as well as residential urban connections and small-business, in alternative or substitution of wired connections, backhaul for radio base stations able to bypass the PSTN or to Internet WiFi hot-spot, extension to rural areas of broadband services already available in the urban areas. The bandwidth for WiMAX equipment can vary from 1.5 to 20 MHz (channel size), being able to support different throughput, from a few hundred kbps for typical residential users or small offices, or an E1 trunk (2 Mbps) , up to 70 Mbps. Fig 4.1a shows the typical uses of WiMAX in different situations like small home small office (SOHO), backhaul etc. while fig 4.1b shows salient features of WiMAX.

Fig 4.1a

Fig 4.1b

4.2 WiMAX and WiFi WiMAX is similar to another very popular mode of digital wireless acces standard, the WiFi (very often referred to as the ‘big brother’ of WiFi ! ). WiMAX is superior to WiFi in many respects. But WiFi and WiMAX should not be thought of competing technologies. While WiMAX can provide high capacity wireless links to residential sites residential like colonies or apartments and business sites like office buildings, WiFi allows the extension of such connections inside the buildings or smaller outdoor areas through wireless LAN. Therefore WiMAX and Wi-Fi are complementary technologies, defined to work together and able to ensure the best connection according to user needs. Fig 4.2 shows the comparison between WiMAX and WiFi.

Fig 4.2

4.3 WiMAX: Agencies and policies involved The WiMAX Forum: It was created in April 2002. The WiMAX Forum is a no-profit organization that groups companies promoting the broadband access based on the wireless communication standard IEEE 802.16 for Metropolitan Area Network (MAN). WiMAX Forum activities aim to: • support the standardization process of IEEE 802.16 for MAN • select and promote some of the WiMAX profiles defined in the 802.16 • certificate the interoperability between WiMAX equipment of different suppliers • make WiMAX a universally accepted technology It is important to underline that WiMAX is not based on new revolutionary technologies, but on technologies tested and already applied in existing radio systems in the past. The WiMAX main value is therefore the boost to the standardization. The work in progress for a fast reinforcement of the WiMAX industry standard is essential to make this wireless technology a stable, reliable and cost-effective solution to be applied by millions of users in the last-mile connections. Companies joining the WiMAX Forum cover more than 75% of the whole broadband wireless access sector. The IEEE: IEEE refers to the Institution of Electrical Electronics Engineers. It is the supreme body that deals with technologies and standards in the field of electronics, electrical and computer engineering. WiMAX is within IEEE 802.16 working group which deals with technologies related to wireless broadband access. From the IEEE standards, The present WiMAX is related to the “d” release of the standard IEEE 802.16, approved during August 2004, and it supports broadband wireless “fixed” connections, while the evolution of 802.16e is in development, focused on the broadband wireless access in mobility. Fig 4.3 shows various IEEE 802.16 standards with their main features.

The frequency spectrum of WiMAX can be from 2 to the 11 GHz, but the WiMAX Forum is focusing at first on the 3.5 GHz band. There are many carrier modulation and channel duplexing techniques associated with WiMAX like OFDM, OFDMA, FDM etc. To operate in the de licenced zone of spectrum, mandatory carrier modulation technique is the Orthogonal Frequency Division Multiplexing (OFDM) with 256 points FFT. Guidelines for WiMAX in India: “Broad Band Policy announced by the GOI has de-licenced the use of 2.4 GHz (ISM band) both for indoor and outdoor applications and is being extensively used for WiFi and other propritory technology based on 802.11 a/b/g standard for broad band communication in the country. No royalty is to be paid to WPC for using de-licensed band, but at the same time GoI does not provide any protection from interference from other users in vicinity. Release of 5.4 GHz to 5.7 GHz band for outdoor uses is under consideration with WPC, GOI. ICT infrastructure requirements for e Governance was kept into consideration while designing the policy announced. National Frequency Allocation Plan (NFAP) published by the WPC, DoT, Government of India is available on the Government website and can be refered by the SWAN designers.” As given in the Wireless Guidelines issued by GoI for SWAN projects. 4.4 WiMAX networks A typical wireless Metropolitan Area Network architecture is similar to the access part of a mobile network, with radio base stations located to optimise PMP connections and able to provide services in a coverage area depending on frequency, transmitted power and receiver sensitivity. Typically radio base stations are connected to the backbone network through optical fiber or microwave PTP link. When the communication is between one sender and one receiver, it is called point-to-point (PTP) link. When the communication is between one sender and multiple receivers, it is called point-to-multipoint (PMP) link. Broadcast and

multicast connections are examples of PMP communication. The point-to-multipoint (PMP) operation mode is used for communication between a base station and multiple subscriber stations while point-to-point (PTP) operation mode is used for communication between two base stations (for backhaul purposes). Communication made possible when the transmitter and receiver(s) are placed on high-rise towers so as to avoid all physical obstacles (like trees and buildings) between them such that they are able to “see” each other, is called line-of-sight (LOS) communication. Where LOS communication is not possible (e.g. when transmitters/receivers are devices inside a home), signals transmitted from the receiver undergo attenuation and multipath distortion (after bouncing off trees and buildings). This type of communication is called non line-of-sight (NLOS) communication. Different flavours of WiMAX support LOS or NLOS. A PTP link is usually LOS while PMP links are generally NLOS. In its simplest form, a WiMAX network may consists of a WiMAX base station and multiple WiMAX subscriber stations (fixed or mobile). WiMAX base station is usually mounted on a tower. WiMAX subscriber station is a WiMAX customer premise equipment (CPE) that is located inside the house. WiMAX base station on the tower communicates wirelessly with the WiMAX subscriber station located inside the house. WiMAX base station on the tower is physically wired to the backbone telecom network of a telecom network provider through fiber optic cables. At the service provider’s point of presence (PoP), data aggregated from all base stations are sent to the network backbone through high-speed high capacity fiber-optic cables. Fig 4.4a shows a typical WiMAX network.

Fig 4.4a: a typical WiMAX network

In WiMAX networks it is also possible for a building to have a rooftop antenna with WiMAX equipments installed to access WiMAX signals and the received WiMAX signals can be made available to users inside by a local LAN or WiFi. Fig 4.4b represents such a case.

Fig 4.4b

A WiMAX radio base station can be made flexible enough to be able to control a small number of user terminals or to work as a sophisticated equipment able to manage thousands of customer equipment ensuring all grades of service. 4.5 WiMAX for the last mile in BSWAN BSWAN operates on the telecom network provided by BSNL which is largely on optical fiber media and partially on copper. DHQs are connected to SHQ at Patna fully through optical fiber links while in most of the cases copper media are used in the local loop. Due to the limitations of copper media discussed in chapter 3, the performance of the links based on copper media is not upto mark and the average uptime of the links which have copper in the last mile is lower than required. Therefore deploying alternate means of connectivity are being discussed. Of all the alternate means available that can be used in last mile instead of copper, like using OFC for the last mile or having ISDN backup, WiMAX offers the best trade off between cost effectiveness and quality of service offered. When one goes for using WiMAX in the local loop all the problems of using physical media like cables and wire, of some have been discussed before, between the two ends are bypassed. There is only one time cost involved in installing WiMAX equipments as opposed to a heavy amount paid to the service provider on a regular basis for providing leased line solutions. As GoI has de licenced the use of some particular frequency bands for the use in wireless access technologies, there is no issue of getting a licence by paying licence fee if operated under those frequency bands. This makes costs involved even lower.

Also, if the CSCs have also to be connected to BSWAN and as many many of them would be located in such remote areas where even electricity has not reached today, taking optical fiber or copper media there would be very difficult as well as prohibitively expensive. In such cases WiMAx is the best solution available today. WiMAX can be implemented in BSWAN for the last mile in two phases: In phase 1, WiMAX should replace the copper link between a BHQ and the nearest BSNL exchange upto which there is connectivity available on OFC. This link forms the last mile in the connectivity of a BHQ to the corresponding DHQ which has been discussed in chapter 2. It is suggested to erect a WiMAX base station tower on the rooftop or anywhere in the close vicinity of the BSNL exchange. Another WiMAX base station has to be erected in the BHQ premises. The 2 Mbps link from the DHQ reaching the BSNL exchange which was earlier fed into the modem located inside the exchange should now be fed to the WiMAX base station. There should be a point to point line of sight WiMAX connection between the two above stated towers. The 2Mbps link from the DHQ can thus be backhauled to the BHQ. The link from the DHQ can be received in the BHQ using the WiMAX CPE through WiMAX antennas installed on the base station tower.. The link can be interfaced with a LAN to allow multiple users in the BHQ. To connect CSCs located in the administrative area of a BHQ, the base station tower of the BHQ should be equipped to make point to multipoint connections with the CSCs. These PMP connections should be Non Line of Sight (NLOS). The CSCs should have a WiMAX CPE installed either on the device (PC) or using external antenna. The WiMAX signals received can be used by multiple users through the use of a switch/ hub. Fig 4.5 shows the case. In Phase 2 the copper link for the last mile connecting horizontal offices like VAT, treasuries etc. should be replaced by WiMAX. For this a WiMAX MAN can be established across the district headquarter town. WiMAX base stations can be erected in suitable locations across the town providing point to multipoint non line of sight connections just like mobile base stations. If possible, BTS towers of existing mobile networks can be rented to install WiMAX equipments on them. Individual base station towers can be connected to each other through PTP LOS backhaul or underground OFC network. Aggregated data from all the base station towers in the town can reach to a master WiMAX control center located somewhere in the town (preferred nearest to the DHQ or perhaps somewhere in the DHQ itself building if possible) through a wireless or OFC backbone network. Then this data can b sent to the DHQ router through OFC. Users in horizontal offices can access the WiMAX network the same way users in a MAN do. Individual CPEs could be used for user PCs in offices or a rooftop antenna with MiMAX equipments can be installed to intercept the WiMAX signals and they are made available to the users across the building through a LAN or WiFi. Fig 4.5b shows the case.

Fig 4.5a

Fig 4.5b

In smaller towns where all the horizontal offices van be expected to be present within a radius of 5 to 10 Kms radius from the DHQ, WiMAX network for horizontal connectivity can be established in a simpler way. The WiMAX control station can be present right inside the DHQ building. A rooftop WiMAX tower can be erected which can provide point to multipoint WiMAX network that can provide coverage to all the horizontal offices present inside the town. Fig 4.5c shows this case.

Fig 5.5c

4.6 Advantages of using WiMAX in local loop The following can be some of the advantages of using WiMAX technology:      

WiMAX provides broadband speeds for voice, data, and video applications WiMAX provides wide coverage, high capacity at low cost There is no cost involved to be paid to service provider on regular besis as there is always in the leased line case. WiMAX being a wireless technology, costs less because there is no need for service providers to purchase rights-of-way, dig trenches and lay cables. WiMAX can be used for backhaul connectivity, fixed and mobile broadband Internet access for data and voice using VoIP (Voice-over-IP) technology. Because WiMAX is based on wireless technology, and because it is cost effective, it is easier to extend broadband Internet access to suburban and rural areas. This helps in



bringing wireless broadband to the masses and to bridge the digital divide that exists especially in developing and underdeveloped countries. As some bands are de licenced by GoI, there is no tension of getting licences or paying licence fees on a regular basis if operated under those bands.

The following table summarises the comparison of using wired (copper) and wireless (WiMAX) media in the last mile: Copper Being a wired connection, more reliable

WiMAX Being wireless, not as reliable

Suffers several last mile problems (crosstalk, No suffering with the last mile problems as attenuation etc.) discussed Bitrate limited to 2Mbps

Much higher bitrates as high as 70 Mbps can be achieved

Wires can be broken, cut or theft

No physical wires present at all

Higher expenses due to high leased lines One time installation costs only charges that are paid periodically As fixed connection, subscriber offered.

no

mobility

of Subscriber can roam within the coverage area.

Copper local loop cannot be taken to very WiMAX can be taken to remote areas as remote areas. well.

Conclusion Bihar, which was lagging far behind a few years back in the field of IT in government works i.e. in e-governance, is today among the forerunners. The successful implementation of e-government projects specially BSWAN, in a time little over three years is one of the greatest achievements of the present regime in Bihar. The way the BSWAN project has been implemented and is being operated is one of the most talked about success stories in the IT sector today. The present report gives the reader a complete description of the working of BSWAN besides giving an overview of what e-government actually is. The report also covers, in brief, some of the challenges faced by BSWAN and their possible solutions. However, main focus of the work has been the last miles connectivity issues and their possible solutions which have been discussed in details. The report, in the last chapter, also gives a descriptive account on the working of an upcoming but very promising technology, the WiMAX and also how it can be used for last mile connectivity in the BSWAN. Thank you Yawar Abbas. Patna , 7th July 2009