comp2110-how-the web-works.pdf

COMP2110 WEB TECHNOLOGY How the Web Works Dr Kate Stefanov In this video YOU WILL LEARN 1. What is the World Wide Web (WWW) 2. Terms and acronyms: TCP/IP, HTTP, HTML, URL 3. How do we find content on the Web 4. What are browsers Department of Computing Comp2110 Web Technology TCP/IP Standard low-lev...

COMP2110 WEB TECHNOLOGY How the Web Works Dr Kate Stefanov In this video YOU WILL LEARN 1. What is the World Wide Web (WWW) 2. Terms and acronyms: TCP/IP, HTTP, HTML, URL 3. How do we find content on the Web 4. What are browsers Department of Computing Comp2110 Web Technology TCP/IP Standard low-level protocol since 1982 Transmission Control Protocol / Internet Protocol (TCP/IP) Point to point communication between computers IP address (numerical) e.g. 192.168.1.137 or 10.13.111.126 IPv4 – 32 bit addresses IPv6 – 128 bit addresses DNS (Domain Name System) Translates IP addresses (numbers) into hierarchical name spaces e.g. mq.edu.au, science.mq.edu.au, google.com Department of Computing Comp2110 Web Technology HTTP 1 More abstract protocol Sits on top TCP/IP WWW – part of the Internet (email, IRC, etc) WWW uses HTTP Two modes: request and response Text-based; Header and body Header: metadata, information about the communication Body: data if any Department of Computing Format: HTTP / [Message] Example (request): GET /storefront.html HTTP / 1.1 Accept: text/* Comp2110 Web Technology HTTP 2 Format of Response: Example (request): GET /storefront.html HTTP / 1.1 Accept: text/* Department of Computing Example (response): HTTP / 1.1 200 OK Comp2110 Web Technology URL Universal Resource Locator Contains information on how to acquire resource Format: : For HTTP schema: http://[:][/][?][#] Examples: http://example.com http://comp.mq.edu.au/~kate ftp://... Department of Computing Comp2110 Web Technology HTML Hypertext Markup Language HTML documents contain links to other Documents and / or Multimedia resources A markup language – adds information to text, encodes appearance, behaviour Other: XML, LayTex, RTF Not all documents on the Web are HTML Versions: HTML 4.01 XHTML 1.0 HTML 5 Department of Computing Comp2110 Web Technology HTML Example: Example page Hello world! This is a very short HTML document. Web Browsers Software application Used to access information on the WWW Appearance may differ Developers: check all major browsers and platforms Department of Computing Comp2110 Web Technology Summary TCP/IP HTTP HTML URL Browsers More information https://pwp.stevecassidy.net/web/webworks.html https://www.w3schools.com Department of Computing Comp2110 Web Technology