How web browsers request pages in Intro to Computing - Practice Exercises

Challenge - 5 Problems

🧠 Conceptual

intermediate

What happens first when you type a website address?

When you type a website address (URL) into a browser and press Enter, what is the very first step the browser takes to get the page?

A The browser sends a request to the server asking for the page.

B The browser downloads all images on the page.

C The browser looks up the IP address of the website using DNS.

D The browser renders the page on the screen.

💡 Hint

Think about how the browser finds the website's location on the internet.

Before the browser can ask the server for the page, it needs to find the server's IP address. This is done by asking a DNS server to translate the website name into an IP address.

❓ trace

intermediate

Trace the steps of a browser requesting a page

Put these steps in the correct order for how a browser requests a web page after you type a URL:

A 1,2,3,4

B 1,3,2,4

C 2,3,1,4

D 2,1,3,4

💡 Hint

Remember the browser must find the IP address before sending a request.

The browser first looks up the IP address (DNS lookup), then sends the HTTP request, receives the data, and finally renders the page.

❓ identification

advanced

Identify the protocol used when a browser requests a page

Which protocol does a web browser use to request a web page from a server?

A HTTP

B SSH

C FTP

D SMTP

💡 Hint

This protocol is designed for transferring web pages.

HTTP (HyperText Transfer Protocol) is the standard protocol used by browsers to request and receive web pages.

❓ Comparison

advanced

Compare HTTP and HTTPS in browser requests

What is the main difference between HTTP and HTTPS when a browser requests a page?

A HTTPS encrypts data between browser and server; HTTP does not.

B HTTP is faster than HTTPS because it uses compression.

C HTTPS uses a different port number but sends data unencrypted.

D HTTP requires a password; HTTPS does not.

💡 Hint

Think about security and privacy when browsing.

HTTPS adds encryption to protect data sent between the browser and server, making it secure. HTTP sends data in plain text.

🚀 Application

expert

What happens if DNS lookup fails?

If a browser cannot find the IP address for a website during DNS lookup, what will happen next?

A The browser will try to load the page from its cache anyway.

B The browser will show an error message saying the site cannot be reached.

C The browser will send the request to a random IP address.

D The browser will automatically switch to HTTPS.

💡 Hint

Consider what happens when the browser cannot find where to send the request.

If DNS lookup fails, the browser does not know the server's IP address and cannot send the request, so it shows an error.