In late 1960 the Advanced Research Projects Agency of USDD funded research on networking that could withstand partial outages (after a nuclear war) i.e. reliable, no central command, equal status, redundant paths
APPANET: one of the first packet switched WANs
Transmission Control Protocols/ Internet Protocol (TCP/IP): the first set of protocols developed for use in an internet
made possible a global Internet that reaches over "5" million computers in schools, commercials organizations, and government and military sites in more than "82" countries around the world
National Science Foundation builds NSFNET based on the ARPANET IP technology
telnet, ftp, gopher, e-mail, MIME, www, CUSeeMe
commercialization and globalization (no pay o.k./necessity)
WWW
is a large-scale, on-line repository of information that user can search using an interactive application program call a browser
is a distributed (documents/pages are distributed across a large set of computers) hypertext/hypermedia (contains information stored in different representations and pointers to other documents/pages) system that supports interactive access
Wed Server and Wed Browser
Communicate using HyperText Transfer Protocol (HTTP)
i.e. The browser contacts a server to retrieve a page of information written in HyperText Markup Language (HTML)
<HTML>
<HEAD>
<TITLE> this is the title </TITLE>
</HEAD>
<BODY>
this is the body <A HREF=http://www.xyz.com URL </A>
</BODY>
</HTML>
The result is a huge sea of interlinked information
The general form of Uniform Resource Locator (URL) is
protocol://computer_name:port/document_name
e.g. http://www.bluemountainarts.com/mailbox123/xyz.html
in this case, when the browser interacts with the Wed server, the two programs follow the Hyper Text Transport Protocol (http)
www.bluemountainarts.com is the domain name used to identify a particular network and computer on the Internet in stead of using IP address 111.111.111.111
Static: each request results in exactly the same response
Dynamic: a fresh document is created for each request
Active: when a browser requests an active document, the server returns a copy of the program that the browser must run locally, thus the browser becomes a programming platform for development of existing and future application programs