What is Networking Flashcards
Basics of Networking(1)
1 - Internet is the physical connection of all computers(a network). Each computer is connected to an even bigger network (ex: home, Workplace, etc).
2 - The Internet is composed of a massive network of satellites, cellular networks, and physical cables buried beneath the ground. We don’t actually connect to the Internet directly. Instead, computers called servers connect directly to the Internet. Servers is a centralized computer that provides data to other computers(like google, Wikipedia, etc.).
3 - The Web is the information on the Internet. We use it to access the Internet through a link like www.google.com.
4 - Your e-mail, chat, and file-sharing programs are also ways you can access the Internet.
Basics of Networking(2)
5 - The machines that we use, like our mobile phones, laptops, video game, consoles and more, are called clients. Clients request the content, like pictures, websites, from the servers. Clients don’t connect directly to the Internet. Instead, they connect to a network run by an Internet service provider or ISP, like Comcast.
6 - ISPs have already built networks and run all the necessary physical cabling that connects millions of computers together in one network. They also connect to other networks and other ISPs.
7 - But how do the clients know how to get to servers? Well, how would you send a letter to someone? You’d put your address(computer is IP address) on the letter and send it to the address of the person you’re sending the letter to.
8 - Think again of the letter analogy we used before. An IP address is your house address, while the MAC address is the name of this recipient of the letter.
Networking Hardware(1)
1 - There are a lot of ways you can connect computers to a network.
- there is an Ethernet cable, which lets you physically connect to the network through a cable.
- Another way to connect to a network is through Wi-Fi, which is wireless networking.
- The last method will go over uses fiber optic cables to connect to a network. This is the most expensive method since fiber optic cables allow greater speeds than all the other methods. Fiber optic gets its name, because the cables contain glass fibers that move data through light instead of electricity. This means that we send ones and zeros through a beam of light instead of an electrical current, through a copper wire.
2 - We don’t just have millions of cables going in and out of computers to connect them together, instead, computers connect to a few different devices that help organize our network together. The first device that your computer connects to is a router. A router (ex: get letters to the building) connects lots of different devices together and helps route network traffic.
Networking Hardware(2)
3 - You want to send a file from Computer A to Computer B. Our packets go through the router and the router utilizes network protocols, to help determine where to send the packet.
4 - What if you wanted to send a packet to a computer not in our network? The packet will get routed outsider network to our ISP’s network. Using networking protocols, it’s able to figure out where Alejandro’s computer is. During this process, our packet is traveling across many different routers switches (mailroom to figure out where to send a letter) and hub(company memo that don’t know who to send to, so they send it to everyone).
Language of the Internet
1 - Think of network protocols like a set of rules for how we transfer data in a network. There are lots and lots of network protocols used and they’re all necessary to help us get our packets in the right place. There are rules that make sure our packets are routed efficiently, aren’t corrupted, are secure, go to the right machine and are named appropriately.
2 - but there are two protocols that you need to know. The Transmission Control Protocol and the Internet Protocol, or TCP/IP for short, which have become the predominant protocols of the Internet.
3 - The Internet Protocol or IP, is responsible for delivering our packets to the right computers. Remember those addresses that computers use to find something on a network? They’re called IP addresses or Internet protocol addresses. The Internet Protocol helps us route information.
4 - The Transmission Control Protocol or TCP, is a protocol that handles reliable delivery of information from one network to another.
The Web(1)
1 - Websites are basically text documents that we format with HTML, or hypertext markup language. It’s a coding language used by web browsers.
2 - A URL, which stands for Uniform Resource Locator, is just a web address similar to a home address. Notice the www in the URL? It stands for World Wide Web. The second portion, google is something we call a domain name.
Anyone can register a domain name. It’s just our website name. Once a name is taken, it’ll be registered to ICANN, the Internet Corporation for Assigned Names and Numbers. Once a domain name is registered with ICANN, no one else can take that name unless it becomes available again
3 - The last part of the URL in this case is .com. But you can also use different domain endings like reddit.net or reddit.org. The different domain name endings are standards for what type of website it might be. So a domain that ends in .edu is mainly used for educational institutions.
The Web(2)
4 - Remember how computers use IP addresses to find another computer? Well, you can do the same if you wanted to find a computer on the Internet. (172.217.6.46 is google). DNS acts like our Internet’s directory and lets us use human readable words to map to an IP address. The computer doesn’t know what google.com is. It only knows how to get to an IP address. With DNS, it’s able to map Google’s IP address with google.com. Every time you go on a website, your computer is performing a DNS lookup to find the IP address of the website name you typed in.
