In any case, if you are connected to the Internet, your computer has a unique IP address. It's called ping , probably after the sound made by older submarine sonar systems. If you're using a flavor of Unix, get to a command prompt. Type ping www. The pinged computer will respond with a reply. The ping program will count the time expired until the reply comes back if it does.
Also, if you enter a domain name i. More on domain names and address resolution later. Protocol Stacks and Packets So your computer is connected to the Internet and has a unique address.
How does it 'talk' to other computers connected to the Internet? An example should serve here: Let's say your IP address is 1. The message you want to send is "Hello computer 5. Obviously, the message must be transmitted over whatever kind of wire connects your computer to the Internet. Let's say you've dialed into your ISP from home and the message must be transmitted over the phone line. Therefore the message must be translated from alphabetic text into electronic signals, transmitted over the Internet, then translated back into alphabetic text.
How is this accomplished? Through the use of a protocol stack. Every computer needs one to communicate on the Internet and it is usually built into the computer's operating system i. Windows, Unix, etc. Hardware Layer Converts binary packet data to network signals and back.
If we were to follow the path that the message "Hello computer 5. If the message to be sent is long, each stack layer that the message passes through may break the message up into smaller chunks of data. This is because data sent over the Internet and most computer networks are sent in manageable chunks. On the Internet, these chunks of data are known as packets.
Each packet is assigned a port number. We need to know which program on the destination computer needs to receive the message because it will be listening on a specific port. This is where each packet receives it's destination address, 5. Now that our message packets have a port number and an IP address, they are ready to be sent over the Internet. The hardware layer takes care of turning our packets containing the alphabetic text of our message into electronic signals and transmitting them over the phone line.
On the other end of the phone line your ISP has a direct connection to the Internet. The ISPs router examines the destination address in each packet and determines where to send it. Often, the packet's next stop is another router. More on routers and Internet infrastructure later.
Eventually, the packets reach computer 5. As the packets go upwards through the stack, all routing data that the sending computer's stack added such as IP address and port number is stripped from the packets. When the data reaches the top of the stack, the packets have been re-assembled into their original form, "Hello computer 5. But what's in-between?
What actually makes up the Internet? Let's look at another diagram: Diagram 3 Here we see Diagram 1 redrawn with more detail. The physical connection through the phone network to the Internet Service Provider might have been easy to guess, but beyond that might bear some explanation. The ISP maintains a pool of modems for their dial-in customers. Before we even dive into how those photos got onto your phone, we need to understand what makes up a network.
Networks are groups of interconnected devices. Though not a node themselves, they allow computers and electronic devices to join a network as a node.
Network switches are central nodes that forward messages between nodes in the same network by rapidly creating and deleting connection points. You can think of them as the managers of the network, maintaining the flow of information between the devices in a network, whether wireless or wired. A network router is a device that connects two or more separate networks.
Routers forward data to other routers of different networks until the data has reached its destination. WAPs allow nearby computers and nodes to interact with a network wirelessly, usually via WiFi.
Multiple WAPs can be connected to extend the wireless capability range of a network, such as in a large building. You can have a strong connection to your WiFi, but no connection to the internet and vice versa.
The origin of the internet began in the late s and early s from a new network technology created by the U. Department of Defense. Its purpose was to connect various Department of Defense scientists and researchers across the United States working on defense projects. As more and more networks joined the system, the internet began to take shape. It is worth noting there are several other services built on top of the Internet, such as email and IRC.
Intranets are private networks that are restricted to members of a particular organization. They are commonly used to provide a portal for members to securely access shared resources, collaborate and communicate. For example, an organization's intranet might host web pages for sharing department or team information, shared drives for managing key documents and files, portals for performing business administration tasks, and collaboration tools like wikis, discussion boards, and messaging systems.
Extranets are very similar to Intranets, except they open all or part of a private network to allow sharing and collaboration with other organizations. They are typically used to safely and securely share information with clients and stakeholders who work closely with a business. Often their functions are similar to those provided by an intranet: information and file sharing, collaboration tools, discussion boards, etc. Both intranets and extranets run on the same kind of infrastructure as the Internet, and use the same protocols.
They can therefore be accessed by authorised members from different physical locations. Skip to main content Skip to search Skip to select language Learn web development Common questions How does the Internet work? Change language. This article discusses what the Internet is and how it works. Prerequisites: None, but we encourage you to read the Article on setting project goals first Objective: You will learn the basics of the technical infrastructure of the Web and the difference between Internet and the Web.
How the internet Works in 5 minutes : A 5 minute video to understand the very basics of Internet by Aaron Titus. How does the Internet work? Detailed well visualized 8 minute video. By connecting computers to routers, then routers to routers, we are able to scale infinitely. Every computer or device can be said to have a unique, numbered IP address.
IP addresses are numbers, not words. The internet works by using a Packet Routing Network to allow computers to send and receive messages using Internet Protocol addresses and a Transfer Control Protocol.
The internet allows computers to share information by sending messages back and forth across a wide, complex system. The system that handles this communication is called a Packet Routing Network. This is why access to the internet usually requires a router.
A router is a piece of hardware that allows multiple computers to connect to one another in order to create this network. The router is an essential piece of equipment that guides the packets to their destinations.
The process of transfer is not always smooth. Sometimes things go wrong. Packets may be left behind or lost. Here's what it looks like in step-by-step form. This is how the internet works, step by step. It's pretty simple, actually.
It gets more complicated when more users are added to the system. Consider this. Much the same as a simple conversation, the message can be a question. This basic interaction is how the internet works.
One computer asks another computer for information. Information requested; information delivered. The two computers talk back and forth. It is still very much like conversation. Some conversations are one-way. Some conversations are two-way.
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