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diff --git a/docs/tutorials/009/page01.html b/docs/tutorials/009/page01.html deleted file mode 100644 index 9483531d89d..00000000000 --- a/docs/tutorials/009/page01.html +++ /dev/null @@ -1,61 +0,0 @@ -<!-- $Id$ --> -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.04 [en] (X11; I; Linux 2.0.32 i486) [Netscape]"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 009</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 009</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Sending and receiving datagrams again</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> - -<P>In our previous tutorial, we created a datagram listener and a couple -of clients that would send it datagrams. That server would respond -to any datagram sent to the TCP/IP port at which the server was listening. -What we really want to do, however, is to have the server only respond -to clients that meet some criteria. - -<P>Why is this important? - -<P>Imagine you're writting a distributed system that will have many server -applications. Each of those will probably listen at different (and -well-known) TCP/IP addresses so that clients can find each server -without confusion. However... In a large system you might have -several <I>versions</I> of the same server running at the same time*. -You probably don't want those servers running at different addresses since -that breaks the well-known address requirement. - -<P>By creating a datagram listener similar to the last tutorial, a client -can send broadcast datagrams to locate all of the servers listening at -the well-known address. By adding a thin protocol layer into -the datagram contents, the servers can be selective about which clients -they respond to. Thus, if each client sends its version signature -in the broadcast, then the servers can choose to respond only to clients -with matching versions. -<P> -Kirthika's Abstract: -<UL> -Here, the client uses datagrams for discovery of the server in the -subnet and also sends a signature for authentification. The server -decides on replying to the client depending on the signature. The only -changes from the previous tutorial are in the addition of an extra -signature matching portion on the server side and providing timeout -values on the client side which allows the send() and recv() calls to -return on a timeout if the target party fails to respond. -<P> -This feature of discrimnation depending on the client signature could be -used for security reasons or version confirmation by the server. -</UL> -<P><FONT SIZE=-1>*Note: I'm making the assumption that your multiple -server versions will be running on different hosts since you can only have -one server listening at the well-known address on a given host.</FONT> - -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page02.html">Continue This Tutorial</A>]</CENTER> |