There is also another type of protocol, called UDP. It is used in some situations
instead of TCP. Its function will not be discussed here.
A microcontroller, with a TCP/IP stack and HTTP sub-protocol in software, becomes
an Embedded Web Server (HTTP TCP). The TCP/IP packets can be sent over an
Ethernet connection to a waiting computer (Win9x, Linux, WinCE, SUN) with a
Standard #2 The Browser
The web browser has become the standard in document presentation. In its most
basic form, a web browsers function is to take a text-based document that is
formatted by a markup language called HTML and present the document in a visual
display, usually a computer monitor. In the Client/Server model (see below), the
HTML pages are stored on the server. They are then served, thru the HTTP TCP/IP
protocol, to the browser, which receives the pages and formats the page
appropriately for the users viewing.
The Client-Server Model
TCP/IP networks follow the client-server model, detailed in the following diagram:
The Server stores data that is served to a client. In the case of the World Wide
Web, a server stores web pages which can be sent, on demand, to a client. The
server typically consists of the data to be sent to a client, an implementation of a
TCP/IP protocol stack, and a physical connection to a network that is connected to
the vast backbone that is the Internet.
A Client is simply any type of computer that has a physical connection to the Internet
backbone with a TCP/IP protocol stack. The Client also contains an important piece
of software called a Browser.