Why change something if it works? To give you some sort of reference on how fast that is, the circumference of the Earth is about 40 km. This means that the packet can go 5 times around the globe in a fiberoptic cable. But we are not done. Because packets can move even faster in the air. Without interference, they can reach speeds of up to That is two hundred thousand one hundred kilometers per second or miles per second.
That is insane. In the air, the packet can go 7 times around the Earth, at the same time it takes you to blink your eye. Things like routers, switches, and other nodes do not support this kind of speeds unsurprisingly so they are the bottlenecks. Think about that the next time you are thinking that your internet is slow. This is the good thing with the internet, and something that has made the internet become so big as it actually is what I think anyway.
There is no one that owns the internet. There is no government, no company, no organization. There is no CEO on the top that can go bad and shut it down any minute. Here, many organization and companies provide their hardware for the internet to work efficiently.
Your ISP, for example, has servers, switches, and routers that make their part of the internet working as it should. They are then connected to another company or organization that take over. So, if all companies in the whole world press the off-button at the same time, the internet would go down. Because of the above, there is no one that is responsible for the overall internet. There are organizations that will standardize technology and infrastructure, so that is easier for these companies to talk to each others.
However, these organizations are not responsible for the internet. Many people now use internet and wifi, but not all of them are really concern about their secure and safe internet connection. I am not an internet technology expert, but I love people share about technology and teach people about the digital security.
Thanks you for this amazing post, this is lovely. The speed on light in a fiber optic cable with air at optimal conditions can travel at IP stands for Internet Protocol; more on this later. The picture below illustrates two computers connected to the Internet; your computer with IP address 1.
The Internet is represented as an abstract object in-between. As this paper progresses, the Internet portion of Diagram 1 will be explained and redrawn several times as the details of the Internet are exposed.
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. This is managed by some form of computer usually a dedicated one which controls data flow from the modem pool to a backbone or dedicated line router.
This setup may be refered to as a port server, as it 'serves' access to the network. Billing and usage information is usually collected here as well. From here the packets will usually journey through several routers and over several backbones, dedicated lines, and other networks until they find their destination, the computer with address 5. But wouldn't it would be nice if we knew the exact route our packets were taking over the Internet?
As it turns out, there is a way This one is called traceroute and it shows the path your packets are taking to a given Internet destination. Like ping, you must use traceroute from a command prompt.
In Windows, use tracert www. That's part of what makes the Internet so robust and fast. Packets will travel from one machine to another until they reach their destination.
As the packets arrive, the computer receiving the data assembles the packets like a puzzle, recreating the message. All data transfers across the Internet work on this principle. It helps networks manage traffic -- if one pathway becomes clogged with traffic, packets can go through a different route.
This is different from the traditional phone system, which creates a dedicated circuit through a series of switches. All information through the old analog phone system would pass back and forth between a dedicated connection. If something happened to that connection, the call would end. That's not the case with traffic across IP networks.
If one connection should fail, data can travel across an alternate route. This works for individual networks and the Internet as a whole. For instance, even if a packet doesn't make it to the destination, the machine receiving the data can determine which packet is missing by referencing the other packets.
It can send a message to the machine sending the data to send it again, creating redundancy. This all happens in the span of just a few milliseconds.
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