A global, public network of computer networks. The largest computer network in the world. Computer Network A collection of computing devices connected to share resources such as: Files Software Processors Storage and printers

Internet technology and the physical connections between devices support many applications….. Such as…. and the Web. Provides a convenient and low-cost form of communication over the internet. Web: Provides a convenient method of sharing information and services.

Web = Internet ?? Internet Provides the technological infra-structure on which the Web and other Internet-based services depend. Web Provides a convenient platform for delivering information and services using the Internet Communicating Sharing Learning Finding entertainment Making new friends

Internetwork Networks joined together into larger networks so that users on different networks can communicate and share data’s Intern Today’s Internet joins together networks of over 500 million computers (or Internet hosts) to create the world’s largest internetwork

Digital Divide: The difference between those that have access to the internet and those that don’t. The Internet is a combination of hardware, protocols, and software. Hardware : provides the physical cables and devices that control and carry Internet data. Protocols: the rules that are implemented in network software and hardware to establish connections between two or more computers to allow them to communicate. Software: Allows users to interact with the Internet to access information and services.

Network Service Providers: A company that provides backbone services to an Internet service provider The Internet backbone refers to the principal data routes between large, strategically interconnected networks and core routers in the Internet. It is made up of many national and international communication networks that are owned by major telecom companies such as AT&T and Sprint. These companies agreed to connect their networks so that users on all the networks could share information over the Internet.

Network service providers enable Internet users to connect to their networks through utility stations called “points of presence” (POPs) The POP’s act as the hubs, and the connections they provide, the spokes.

INTERNET Users connect to the Internet through an Internet Service Provider (ISP) Which connects to the network service provider (NSP) through a point of presence (POP) ISPPOPNSP

Succeeding with Technology Bandwidth o is the transmission capacity of a communications channel Broadband o high-bandwidth communications systems Narrowband o Systems with less capacity Note: The bandwidth of a digital channel is usually measured in bits per second (bps).

TCP/IP Transmission Control Protocol/Internet Protocol Policies and procedures for transmitting over the internet. Data Packet Small group of bytes that includes the data being sent and a header containing information about the data, such as…. destination origin size identification number

Succeeding with Technology

Internet Protocol (IP) The Internet Protocol (IP) defines the format and addressing scheme used for the packets All devices connected to the internet have a unique IP Address IP Address: a unique 32 bit identifier for internet hosts. Static: permanently assigned to a particular computer Dynamic: assigned to computers as needed.

Succeeding with Technology Internet Protocols Protocols make the internet possible TCP/IP provides a standard that is fairly easy to implement, public, free, and extensible The Internet is not owned, operated, or controlled by any single entity TCP/IP is glue that holds the Internet together

Succeeding with Technology IP Addresses The IP part of TCP/IP defines the format for the addresses that identify computers on the Internet These addresses are called IP addresses An IP address is a series of numbers, such as o It is separated into four sections by periods o Each section’s number cannot exceed 255 o Each address requires __ bits (8 bits per section)

Succeeding with Technology People find it difficult to remember long strings of numbers, so host computers also have names called domain names Domain name – “fully qualified domain name” (FQDN), usually typed in all lowercase o Key component of URLs and addresses o www. msu.edu/biologycatalog.htm - is the domain name A domain name ends with an extension that indicates its top-level domain Disputes

Succeeding with Technology Domain Name → IP Address Each name corresponds to an IP address Domain name system – Huge database that houses the names and IP addresses Domain name servers – Computers that house the database

Internet Software Two basic architectures: o Client/server  Client makes a service request  Server provides the service  Port  Logical addresses on the server Client/server technology is the basis of Internet services such as and the Web and uses server computers to distribute data to client applications such as Internet Explorer o Peer-to-peer (P2P) networking  F acilitate communications directly between clients

Peer-to-peer Networking Succeeding with Technology

The protocol of the Web is called HTTP Hypertext Transfer Protocol (HTTP) – controls communication between Web clients and servers. A Web client is commonly called a Web Browser. Markup Languages A markup language is used to describe how information is to be displayed. The primary markup language that is used to specify the formatting of a Web page is called Hypertext Markup Language (HTML)