Computer networking by Dr. Jayarama Reddy
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The document discusses the integral role of computers and the internet in bioinformatics, detailing network types, internet service providers, and the evolution of email and web technologies. It highlights supercomputers used for large-scale computations, describes secure intranets and extranets for organizational information sharing, and outlines web navigation challenges, including the use of search engines. Furthermore, it addresses the significance of virtual private networks for online privacy and the distinction between the surface web and the dark web.
Computer networking by Dr. Jayarama Reddy
- 2. Bioinformatics almost completely depends on Computers and Internet. Growth and development of Bioinformatics and Computer Science has occurred simultaneously. Internet has become an integral part of human life today. Let us Understand How does Internet Work.
- 4. A network connects computers by means of cabling systems, specialized software, and devices that manage data traffic.
- 5. •Networks are collections of computers, software, and hardware that are all connected to help their users work together. •A network enables users to share files and resources, such as printers, as well as send messages electronically (e-mail) to each other. •Computer networks fall into two main types: client/server networks and peer-to-peer networks.
- 8. List of top 30 Internet Service Providers: There were 358 internet service providers (ISPs) offering broadband and narrow band internet services in India. Top 30 Internet Service Providers (ISP) of the World. India stands at No.3
- 9. List of top 10 broadband service providers in India • DEN broadband • Airtel • BSNL • Hathway • Hayai • Act Fibernet • You broadband • Spectranet • AsiaNet • Jetspot Fibre
- 10. A supercomputer is a computer that performs at or near the currently highest operational rate for computers. Supercomputers are used for scientific and engineering applications that must handle very large databases or do a great amount of computation. Ak e[F N
- 11. US Department of Energy and IBM unveiled Summit, America’s latest supercomputer at present.
- 12. Two supercomputers from India, Pratyush and Mihir, ranked in at 67th and 120th spot on the world’s top list.
- 13. Mobile Phone Revolution or Revolution by Mobile Phones? Mobile Phones are connected by S I M (Subscriber Identity Module)
- 14. Internet of Things provides a layer of digital intelligence that will improve on the “smartness” of everything man uses today.
- 15. On October 29th 1969, the first message was sent from computer to computer on ARPANET. It was in 1971 when Ray Tomlinson invented and developed electronic mail, as we know it today, by creating ARPANET's networked email system. Electronic Mails
- 16. Units of Data · 8 Bits = 1 Byte · 1024 Bytes = 1 Kilobyte · 1024 Kilobytes = 1 Megabyte · 1024 Megabytes = 1 Gigabyte · 1024 Gigabytes = 1 Terabyte · 1024 Terabytes = 1 Petabyte · 1024 Petabytes = 1 Exabyte · 1024 Exabytes = 1 Zettabyte · 1024 Zettabytes = 1 Yottabyte · 1024 Yottabytes = 1 Brontobyte · 1024 Brontobytes = 1 Geopbyte
- 24. The Network Information Center, also known as InterNIC from 1993 until 1998, was the organization primarily responsible for Domain Name System domain name allocations and X.500 directory services. Thereafter, the responsibility was assumed by the Internet Corporation for Assigned Names and Numbers (ICANN).
- 32. Las Vegas branch LA Head Office Types of Networks and Connectivity
- 35. NETWORK STANDARDS AND Efficiency and Fidelity of Network Depends on
- 37. Networking Standards • Standards play a significant role in the field of computer networks. • Special-purpose development of communications hard- and software must be avoided because of its high costs and the need to interconnect devices from various vendors. • Standards are designed in a highly formal, structured way to reduce complexity most networks are organized as layers or levels. • The purpose of each layer is to offer certain services to higher layers, which these higher layers can use without knowing how they are implemented. • Only the same layers of two computers communicate through a so called protocol, which is a set of rules for communication at one layer.
- 39. Protocol Layers
- 40. OSI Layers
- 46. Network Layers
- 48. IP Packet
- 51. Internet service provider. An Internet service provider (ISP) also called Internet access provider or IAP is a business or organization that provides to consumers access to the Internet and related services. ISPs can be started by just about any individual or group with sufficient money and expertise. In addition to Internet access via various technologies such as dial-up and DSL, they may provide a combination of services including Internet transit, domain name registration and hosting and web hosting.
- 52. Intranet: A Secure Internet-like Network for Organizations With advancements in browser-based software for the Internet, many private organizations have implemented intranets. An intranet is a private network utilizing Internet-type tools, but available only within that organization. For large organizations, an intranet provides easy access to corporate information for designated employees.
- 53. Extranet: A Secure Means for Sharing Information with Partners While an intranet is used to disseminate confidential information within a corporation, an extranet is commonly used by companies to share data in a secure fashion with their business partners. Internet-type tools are used by content providers to update the extranet. Encryption and user authentication means are provided to protect the information, and to ensure that designated people with the proper access privileges are allowed to view it.
- 54. Hypertext Transfer Protocol (HTTP) is a method used to transfer or convey information on the World Wide Web. Its original purpose was to provide a way to publish and retrieve HTML pages. HTTP is a request/response protocol between clients and servers. The originating client, such as a web browser, spider, or other end-user tool, is referred to as the user agent. The destination server, which stores or creates resources such as HTML files and images, is called the origin server.
- 55. World Wide Web (WWW) is the combination of four basic ideas: • Hypertext: a format of information which allows, in a computer environment, one to move from one part of a document to another or from one document to another through internal connections among these documents (called "hyperlinks"); • Resource Identifiers: unique identifiers used to locate a particular resource (computer file, document or other resource) on the network - this is commonly known as a URL or URI, although the two have subtle technical differences; • The Client-server model of computing: a system in which client software or a client computer makes requests of server software or a server computer that provides the client with resources or services, such as data or files; and • Markup language: characters or codes embedded in text which indicates structure, semantic meaning, or advice on presentation.
- 56. URL Stands for "Uniform Resource Locator." A URL is the address of a specific Web site or file on the Internet. It cannot have spaces or certain other characters and uses forward slashes to denote different directories. Some examples of URLs are http://www.cnet.com/, http://web.mit.edu/, and ftp://info.microsoft.com/. As you can see, not all URLs begin with "http". The first part of a URL indicates what kind of resource it is addressing. Here is a list of the different resource prefixes: • http - a hypertext directory or document (such as a Web page) • ftp - a directory of files or an actual file available to download • gopher - a gopher document or menu • telnet - a Unix-based computer system that you can log into • news - a newsgroup • WAIS - a database or document on a Wide Area Information Search database • file - a file located on your hard drive or some other local drive
- 57. Domain names are used in URLs to identify particular Web pages. Look at the URL and in particular the domain name for clues to its origin. Every domain name has a suffix that indicates what type of organization owns it. .com indicates a commercial business, e.g. www.amazon.com .edu indicates an educational institution, e.g.. www.bangaloreuniversity.edu .ac also indicates educational institution e.g. www.sjc.ac.in .gov indicates a governmental institution e.g. www.karnataka.gov .org indicates an organization e.g. www.biovistas.org .mil indicates military e.g. www.navy.mil United States Navy
- 58. Navigation through Web The Web is vast and disorganized, and the overwhelming majority of what is there is irrelevant to you. Further, the Web changes constantly; new resources appear, old resources become outdated or disappear and the paths and techniques used to access resources change. The following approaches the most useful for identifying biological resources on the web: Search Engines: There are several websites from which you can launch searches. Google is the most commonly used search engine. One of the newest searches services; still listed as Beta. Provides a much shorter, more focused list of sites than most other services. Entrez: It is a search engine to find bioinformatics web locations.
- 59. Virtual Private Network (VPN) A VPN is the easiest and most effective way for people to protect their internet traffic and hide their identities online. As you connect to a secure VPN server, your internet traffic goes through an encrypted tunnel that nobody can see into, including hackers, governments, and your internet service provider.
- 61. Virtual Private Network (VPN) A virtual private network (VPN) gives you online privacy and anonymity by creating a private network from a public internet connection. VPNs mask your internet protocol (IP) address so your online actions are virtually untraceable. Currently, a handful of governments either regulate or outright ban VPNs. Those currently include Belarus, China, Iraq, North Korea, Oman, Russia, and the U.A.E.
- 63. Google Access Only 4% Google Cannot Access 96%
- 64. The dark net accounts 96% on the Internet, also known as the "dark web," is a component of the greater "deep web," a network of encrypted Internet content that is not accessible via traditional search engines like, Google.