Layers of the Internet

What problem does a physical network solve?

Physically connecting devices to one another so that info can move through the network

What problem does an internet protocol solve?

Uniquely identifying people on the internet to route messages between them

What problem does TCP: Transmission Control Protocol solve?

Send large messages over the Internet when accuracy is the most important. You would use either TCP or UDP

What problem does UDP: User Datagram Protocol solve?

Send large messages over the Internet when speed is the most important. You would use either TCP or UDP.

What problem does DNS: Domain Name System solve?

Translates human-readable domains like code.org into example addresses that can be used by the internet

What problem does HTTP: HyperTextTransferProtocol solve?

Allow computer to request and share webpages, audio, images, videos, and other file types on the internet, collectively known as the World Wide Web

How does a physical network work?

Computers are connected to a network via cables or wifi

How does Internet Protocol work?

Each device on the internet is given a unique IP address and the packets of information include to and from IP adresses, allowing routers to know where to send the packets

How does a TCP work?

Messages are divided into packets and sent all at once. Packets are numbered so they can be reordered and missing packets can be requested by the reciever.

How does UDP work?

Messages are divided into packets and sent all at once. There is no error-checking to see if all packets arrived or that they’re in order.

Which is faster: TCP or UDP?

UDP is faster because TCP has to check for errors, but this means that UDP has more errors possible

How does a DNS work?

when you go to a website, your computer contacts a DNS which keeps track of the IP addresses associated with each domain name. The request to and from servers are sent as TCP/IP packets

How does a HTTP work?

Computers communicate in plain text like GET to request files or send data. The server that recieves the request responds with the files requested which are displayed in your brower. HTTP requests are sent between computers over the internet as part of TCP/IP packets

Computing device

A physical device that can run a program, such as a computer, smart phone, or smart sensor.

Computer network

A group of interconnected computing devices capable of sending or receiving data.

Bandwidth

The maximum amount of data that can be sent in a fixed period of time over a network connection, typically measured in bits per second.

Protocol

An agreed upon set of rules that specify the behavior of a system.

Scalability

The ability of a system to adjust in scale to meet new demands

World Wide Web

A system of linked pages, media, and files, browsable over HTTP