Computer Science 302:

Web Development

Gregory M. Kapfhammer

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Office Hours

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Slack Communication

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Color Scheme

Key Concept

Corresponding Diagram

In-Class Discussion

In-Class Activity

Details in the Textbook

Internet protocols

Layered architecture

See Figure 2.1 for more details

Sending packets across the network

See Figure 2.4 for more details

Domain Name System

Let's discover your address!

ifconfig -a

What is localhost?

Domain name registration

https://domains.google/

What does domain registration achieve?

See Figure 2.9 for many details

URLs

Protocol

Domain

Port

Path

Query String

Fragment

Hypertext transfer protocol

Get versus post

See Figure 2.14 for more details

HTTP Response Codes

Try a page that does not exist on my site!

What did you see in your browser?

Which response code was triggered?

Common Responses

301: Moved permanently

307: Temporary redirect

404: Not found

500: Internal server

Fetching a web page

Returning more than HTML files!

What else does the server return?

See Figure 2.15 for more details!

Browser Cache

Client may request the same page multiple times

The browser can store those pages in the cache

The cache can also contain images and other files

How does this influence network bandwidth?

How can this influence web site correctness?

What are the overall trade-offs in cache usage?

What are other browser features?

What are other browser extensions?

Web Servers

Web Server Stacks

Using Databases

Using Scripting Software

Any questions about how the web works?

☺ ☺ ☺

You probably have a lot of questions!

We will answer many this semester!