<HTML ><HEAD ><TITLE >Introduction</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK REL="HOME" TITLE="Connecting X Terminals to Linux Mini-HOWTO" HREF="index.html"><LINK REL="PREVIOUS" TITLE="Copyright" HREF="copyright.html"><LINK REL="NEXT" TITLE="Host Environment" HREF="section2.html"></HEAD ><BODY CLASS="SECT1" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >Connecting X Terminals to Linux Mini-HOWTO</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="copyright.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="section2.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="BACKGROUND" ></A >2. Introduction</H1 ><P >This section provides a brief introduction to the X Window System and the client server model for X terminals and their Linux-based host systems.</P ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="XFREE86" ></A >2.1. What is XFree86</H2 ><P >XFree86 is an Open Source implementation of the X Windows System (X). It provides a client-server interface between mouse, keyboard, video display, and a windowed desktop environment. Because X is network transparent, client programs can be run on a different host machine than the one on which an X Server resides. </P ><P >The XFree86 bundle includes a large array of programs including a terminal emulator, clocks, and a mail interface. This document will focus exclusively on the portions of XFree86 required for maintaining an X Session between an X Terminal and a Linux host. These are the X Display Manager, xdm, an access control programs and the X Font Server, xfs.</P ></DIV ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="AEN36" ></A >2.2. What is an X Terminal?</H2 ><P >X Terminals are diskless networked microcomputers. These systems will generally consist of mouse, monitor, keyboard, RAM, battery-powered NVRAM, and secondary ports for connecting peripheral devices such as printer, bar code scanner, etc. Because they are diskless, X Terminals load their operating system, configuration information, and fonts into memory from a host machine running nfs or tftp, and xfs. </P ><P >The Operating System of an X Terminal will provide basic administrative interface for configuration parameters such as tcp, xdmcp, font path, boot path, and other host-related configurations. It's primary function, however, is to act as an X Server which exchanges mouse, keyboard, and other display information with client applications loaded on a remote host. </P ></DIV ><DIV CLASS="SECT2" ><H2 CLASS="SECT2" ><A NAME="INFRASTRUCTURE" ></A >2.3. Infrastructure Overview</H2 ><P >The canonical way of deploying X Terminal systems on an IP-based network is to use the Bootstrap protocol, bootp, to provide client and host ip addresses and to request a bootable image to mount the operating system. Clients may also store this information from their own NVRAM which mitigates the need for fetching it off of a network. NFS or TFTP is utilized to load the os image and system fonts into RAM on the client machine. XDM provides ip-based authentication and management of the display session using XDMCP. XFS may optionally be run on the host to provide anti-aliasing fonts to the client system (highly recommended). TCP is commonly the transport layer for all client-server interaction. </P ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="copyright.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="section2.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Copyright</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" > </TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Host Environment</TD ></TR ></TABLE ></DIV ></BODY ></HTML >
