ASSIGNMENT OF INFORMATION TECHNOLOGY ON “NETWORKING”
SUBMITTED BY: Janak Behl FD-1 (ISBE-A)
[NETWORKING]
COMPUTER NETWORKING A computer network is a system for communicating between two or more computers and associated devices. It is an interconnection of computers for the purposes of sharing information and resources .
o r r A network is a set of devices (often referred to as nodes) connected by communication links. A node can be a computer, printer, or any other device capable of sending and/or receiving data generated by other nodes on the network. •
A popular example of a computer network is the internet, which allows millions of users to share information
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How to classify networks?
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By Scale Personal area network (PAN) Local Area Network (LAN) Campus Area Network (CAN) Metropolitan area network (MAN) Wide area network (WAN)
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By Connection Method Optical fiber Ethernet Wireless LAN Power line communication
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By Network Topology
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[NETWORKING] Bus network Star network Ring network Mesh network
An example of a network
Applications of Networks Resource Sharing Hardware (computing resources, disks, printers) Software (application software) Information Sharing Easy accessibility from anywhere (files, databases)
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[NETWORKING] Search Capability (WWW) Communication Email Message broadcast Remote computing Distributed processing (GRID Computing)
INTRANET Intranet is the generic term for a collection of private computer networks within an organization. An intranet uses network technologies as a tool to facilitate communication between people or workgroups to improve the data sharing capability and overall knowledge base of an organization's employees. Intranets utilize standard network hardware and software technologies like Wi-Fi, Web browsers and Web servers. An organization's intranet typically includes Internet access but is firewalled so that its computers cannot be reached directly from the outside.
INTERNET The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide. It is a network
of networks that
consists of millions of private, public, academic, business,
and government networks, of local to global scope, that are linked by a broad array of electronic and optical networking technologies. The Internet carries a vast range of information resources and services, such as the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support electronic mail. The Internet has enabled or accelerated new forms of human interactions through instant messaging, Internet forums, and social networking,. Online shopping has boomed both for major retail outlets and small artisans and traders. Business-tobusiness and financial services on the Internet affect supply chains across entire industries. [ASSIGNMENT]
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EXTRANET An extranet is a computer network that allows controlled access from the outside for specific business or educational purposes. Extranets are extensions to, or segments of, private intranet networks that have been built in many corporations for information sharing and ecommerce.
CLASSIFICATION OF NETWORKING Network is classified in the following:1) Geographical a) LAN b) MAN c) WAN LOCAL AREA NETWORK (LAN): A local area network (LAN) links computers in relatively close proximity in order to share files, printers, other resources, and online access. LANs are used at home and in business and can be either wired or wireless. LAN network will allow computers in a home or office to talk to one another, pass files, use a common database, and share a printer or fax machine, to name a few advantages. A high-speed Internet account can also be shared on a LAN to provide online access to all computers connected to the network. METROPOLITAN AREA NETWORK (MAN): Metropolitan Area Network is a computer network usually spanning a campus or a city, which typically connect a few local area networks using high speed backbone technologies. A MAN often provides efficient connections to a wide area network (WAN).
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[NETWORKING] WIDE AREA NETWORK (WAN): A wide area network (WAN) is a computer network covering multiple distance areas, which may spread across the entire world. WANs often connect multiple smaller networks, such as local area networks (LANs) or metro area networks (MANs). The world's most popular WAN is the Internet. Some segments of the Internet are also WANs in themselves. A wide area network may be privately owned or rented from service providers, but the term usually connotes the inclusion of public (shared user) networks.
2) Topological a) BUS b) STAR c) MESH d) HYBRID e) RING BUS TOPOLOGY:
Each node is connected one after the other (like christmas lights) Nodes communicate with each other along the same path called the backbone
Multipoint Advantages: i) ii)
Easy to install Less cables
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[NETWORKING] Disadvantages: i) ii)
Hard to detect fault isolation Bus cable is too important RING TOPOLOGY
The ring network is like a bus network, but the “end” of the network is connected to the first node Nodes in the network use tokens to communicate with each other
Point to point with 2 devices on both sides Advantages: i) Easy to install ii) Maintain: add move delete iii) Fault isolation Disadvantages: i)
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Unidirectional traffic
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[NETWORKING] STAR TOPOLOGY
Each node is connected to a device in the center of the network called a hub
The hub simply passes the signal arriving from any node to the other nodes in the network
The hub does not route the data
Less expensive. One link and I/O port connecting to the hub. No direct traffic between two devices. Advantages: i)
Easy to install
ii) Less cables iii) Maintain: add, move, delete iv) Robustness
Disadvantage: i)
Hub is too important
ii) The hub represents a single source of failure [ASSIGNMENT]
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MESH TOPOLOGY
Example: telephone regional offices Advantages: •
no traffic problems
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Robust. No link failure no
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Privacy security
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Easy to detect the abnormal situation.
effect on others.
Disadvantages: •
Amount of cables, i/o ports
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Efficiency and effectiveness
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Space Cost
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[NETWORKING] HYBRID TOPOLOGY It is formed by combining other network topology like bus, star etc…
A hybrid topology: a star backbone with three bus networks
ADVANTAGES AND DISADVANTAGES OF NETWORK:There are so many benefits with networking it is little wonder that it has become the most highly used tool in Executive and Management job hunting. Advantages are as follows: 1. You can be afforded an opportunity not yet advertised therefore reducing the competition significantly. 2. A job may be specifically created for you based on an employer’s requirement. 3. You are in the enviable position of focusing attention on the qualities and strengths you possess. 4. Networking provides social contact and stimulation. 5. Rather than having to make a cold call or attend an interview with people who are unknown to you, you will have a referral that will make the process easier. 6. Openings are created for you to be opportunistic and flexible. You must actively listen to the communication that is going on around you. 7. Networking is a two way process that can enable you to help others. 8. Networking is a proactive job search method. 9. Networking puts you in control, setting your own pace and course. It is less stressful than sifting through tons of advertisements and is far more productive over time. Unfortunately as in all aspects of life, networking has its disadvantages too.
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[NETWORKING] Disadvantages are as follows: 1. While networking is a very effective technique one must always be aware of the possibility of indiscretion. Choose your contacts wisely and ensure that you maintain confidentiality at all times. 2. Networking can be a waiting game where you have to wait it out patiently for the right opportunity or the right contact to come available. To weigh it up you can clearly see that the advantages greatly outweigh the disadvantages. Put your thoughts together and develop a networking contact list and begin this proactive process and take control of your job search.
THE CLIENT SERVER ARCHITECTURE The Internet revolves around the client-server architecture. Your computer runs software called the client and it interacts with another software known as the server located at a remote computer. The client is usually a browser such as Internet Explorer, Netscape Navigator or Mozilla. Browsers interact with the server using a set of instructions called protocols. These protocols help in the accurate transfer of data through requests from a browser and responses from the server. There are many protocols available on the Internet. The World Wide Web, which is a part of the Internet, brings all these protocols under one roof. You can, thus, use HTTP, FTP, Telnet, email etc. from one platform - your web browser. Some common Internet protocols
HTTP (HyperText transfer Protocol): used on the World Wide Web (WWW) for transfering web pages and files contained in web pages such as images.
FTP (File Transfer protocol): employed for transferring files from one machine to the other.
SMTP (Simple Mail Transport Protocol): used for email.
Telnet Protocol: Used to open telnet sessions.
The web employs a connection-less protocol , which means that after every clientserver interaction the connection between the two is lost. Let us now examine the client-server inter-communication with three models.
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[NETWORKING] Model #1 of the client-server architecture - Static HTML pages
The client (browser) requests for an HTML file stored on the remote machine through the server software. The server locates this file and passes it to the client. The client then displays this file on your machine. In this case, the HTML page is static. Static pages do not change until the developer modifies them. Model #2 of the client-server architecture - CGI Scripts
The scenario is slightly different for CGI applications. Here the server has to do more work since CGI programs consume the server machine's processing power. Let us suppose you come across a searchable form on a web page that runs a CGI program. Let us also suppose you type in the word 'computers' as the search query. Your browser sends your request to the server. The server checks the headers and locates the necessary CGI program and passes it the data from the request including your search query "computers". The CGI program processes this data and returns the results to the server. The server then sends this formatted in HTML to your browser which in turn displays the HTML page. Thus the CGI program generates a dynamic HTML page. The contents of the dynamic page depend on the query passed to the CGI program.
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Model #3 of the client-server architecture - Server side scripting technologies
The third case also involves dynamic response generated by the use of server side technologies. There are many server side technologies today. Active Server Pages (ASP): A Microsoft technology. ASP pages typically have the extension .asp. Personal Home Pages (PHP): An open source technology. PHP pages typically have .php, .phtml or .php3 file name extensions. Java Server Pages : .jsp pages contain Java code. Server Side Includes (SSI): Involves the embedding of small code snippets inside the HTML page. An SSI page typically has .html as its file extension. With these server technologies it has become easier to maintain Web pages especially helpful for a large web site. The developer needs to embed the server-side language code inside the HTML page. This code is passed to the appropriate interpreter which processes these instructions and generates the final HTML displayed by the browser. Note, the embedded server-script code is not visible to the client (even if you check the source of the page) as the server sends ONLY the HTML code. Let's look at PHP as an example. A request sent for a PHP page from a client is passed to the PHP interpreter by the server along with various program variables. The interpreter then processes the PHP code and generates a dynamic HTML output. This is sent to the server which in turn redirects it to the client. The browser is not aware of the functioning of the server. It just receives the HTML code, which it appropriately formats and displays on your computer.
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CASE STUDY
“To create an advanced facilities based, intelligent, next generation communication network, with terabit bandwidth, that will leapfrog India into the center-stage of global communication and information technology spa ce.”
INTRODUCTION TO RELIANCE INFOCOMM Infocomm is the synergy of information and communication services brought about by the digitalization and convergence. In the fast moving and competitive knowledge era, Infocomm is not only a driver of growth but also competitiveness. Reliance Infocomm is revolutionizing telecommunication in India by provisioning services that would match with the leading operators of the most developed countries. These services are the outcome of state-of-the-art network technologies that have been inducted in the Reliance Infocomm network. The network consists of the latest switching, transmission and access technologies. The core of the network consists of fiber deployed throughout the country. Deployed over the fiber media are the DWDM and SDH transmission technologies in ring topology to provide ultra-high bandwidth capacity and failure proof backbone. Besides circuit switched technologies, the backbone also has IP architecture and uses MPLS technology to carry data on an overlay network. In addition gigabit Ethernet will provide broadband services on wireline access. Reliance Infocomm offers a complete range of telecom services, covering mobile and fixed line telephony including broadband, national and international long distance services, data services and a wide range of value added services and applications that will enhance productivity of enterprises and individuals. Mobile telephony, fixed line telephony and Internet service now come with a range of solutions that make the experience of communication entirely different and pleasurable. [ASSIGNMENT]
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[NETWORKING] As a one-stop shop for new age telecommunication solutions, Reliance has laid out one of the biggest fiber optic networks in the world. Digital and broadband-capable, this 70,000 km of terabit capacity network, covering over 600 towns and cities in India, has enabled Reliance to develop a number of innovative communication applications that seamlessly blend together to deliver world-class communication solutions. Telecommunication networks are the infrastructure for provisioning Infocomm services. The Reliance Infocomm network consists of 70,000 kilometers of optical fiber cables spanning the length and breadth of India. These cables can carry thousands of billions of bits per second and can instantly connect one part of the country with another. This physical network and its associated infrastructure will cover over 600 cities and towns in 18 of the country's 21 circles, 229 of the nation’s 323 Long Distance Charging Areas (LDCAs) and broadband connectivity to over 190 cities. This infrastructure will be backed by state-of-the-art information management systems and a customer-focused organization. An interesting aspect of the network is the manner in which these fibers are interconnected and deployed. Reliance's architecture is so fault-tolerant that the chances of failure are virtually nil. Reliance's ring and mesh architecture topology is the most expensive component to implement, but assures the highest quality of uninterrupted service, even in the event of failure or breakage in any segment of the network. Reliance has 77 such rings across the country with at least three alternative paths available in metros. Connected on this topology, the service has virtually no chance of disruption in quality performance. Access networks determine the services that can finally be delivered to customer. The network has wireline access technologies based on fiber as well as copper. Fiber in the access network makes broadband services easy to deploy. The wireless access network deployed for CDMA 1X is spectrum efficient and provides better quality of voice than other networks and higher data rates. CDMA 1X also provides an up gradation path to future enhancements. Through the term broadband connotes relative access speeds, it now generally refers to access speeds of 1.5 Mbps and higher. As content on the Internet and intranet becomes multimedia, broadband technologies are important for accessing the content and to provide video based corporate services. Reliance Infocomm has extended fiber in its access network. This gives the network a capacity to have very high access speeds. Reliance has deployed broadband based on gigabit Ethernet. This will enable Reliance to provision broadband services of high quality and performance. Let’s understand the elements mentioned in the diagram in greater detail: • Building Node (BN): A Building Node (BN) is electronic equipment, which converts optical signals to electronic signals (voice and data). • BA Ring: This is the medium that connects all the Building Nodes about which you have learnt in a previous session. [ASSIGNMENT]
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[NETWORKING] • BAN: At BAN, the information is checked for the recipient’s address and routed accordingly. • Main Access Ring: This is the medium that connects all BANs under an MCN. • MAN: As the traffic in a metropolitan is more, another element called a Metropolitan Access Node is added between the BANs and the MCN. It helps in controlling the large traffic. Each MAN has a
number of BANs under it. Therefore in case of a metropolitan, there will be four layers, (BN) Building Node, BAN, MAN and MCN. • MCN: MCN is the place where information is received from other MCNs, MANs or BANs. Here the information is checked for the recipient’s address and routed accordingly. • Core backbone: This is the medium that connects all MCNs in the country Gateway: The gateway routes international traffic. The network architecture is similar to our postal system.
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[NETWORKING] Wireline and Wireless Network All services run on the same network. However, there is a slight difference between the wireline and wireless connectivity to the customer. In a wireline network, your phone is connected to the Building Node through a copper wire, whereas in case of a wireless network, your mobile phone is connected to a radio station through radio waves. The radio station is connected to the BAN through the Fibre Optic cable. The two types of connectivity are shown below. Wireline Network
BAN
Building node
your wirelene
Co
er cable
Fiber optics
phone
Strengths of the Reliance Network Wireless Network FEATURES Fibre optic based network
BENEFITS Good speed No congestion Reliability
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High capacity Less loss while transmission
Ring topology
Information flows in rings and hence in case of breakdowns has an alternative path to travel on
Free fibre optic cables available
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More capacity can easily be • provided to the existing customers New customers can easily • be added to the existing
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Internet Almost everybody today accesses the Internet for some purpose or the other. Two types of Internet services are there: Dial up Internet A dial up Internet connection is one, which involves dialing through a telephone to the service provider for the connection to be established. It is best suited to the requirements of a single user. This facility offers reliability and quick connectivity. Dedicated Internet A dedicated Internet access is an uninterrupted Internet service at high speeds. Corporate houses, where a large number of users need to connect to the Internet at the same time. For example, a software organization, where a large number of people continuously need to upload and download content to and from the Internet.
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