DMA Mode for CD-ROMs

Like Windows 2000, Windows XP still fails to set the DMA mode correctly for the IDE device designated as the slaves on the primary IDE and secondary IDE channels. Most CD- ROMS are capable of supporting DMA mode, but the default in XP is still PIO. Setting it to DMA won't make your CD-ROM faster, but it will consume less CPU cycles. Here's how: Open the Device Manager. One way to do that is to right click on "My Computer", select the Hardware tab, and Select Device Manager. Expand "IDE ATA/ATAPI Controllers" and double-click on "Primary IDE Channel" .Under the "Advanced Settings" tab, check the "Device 1" setting. More than likely, your current transfer mode is set to PIO. Set it to "DMA if available". Repeat the step

for the "Secondary IDE Channel" if you have devices attached to it. Reboot.

Servlets Introduction

Servlets are Java technology’s answer to Common Gateway Interface (CGI) programming. They are programs that run on a Web server, acting as a middlevlayer between a request coming from a Web browser or other HTTP clientvand databases or applications on the HTTP server. Their job is to:


1. Read any data sent by the user. This data is usually entered in a form on a Web page, but could also come from a Java applet or a custom HTTP client program.

2. Look up any other information about the request that isvembedded in the HTTP request.
This information includes details about browser capabilitie,vcookies, the host name of the requesting client, and so forth.


3. Generate the results. This process may require talking to a database, executing an
RMI or CORBA call, invoking a legacy application, or computing the response directly.


4. Format the results inside a document. In most cases, this involves embedding the information inside an HTML page.


5. Set the appropriate HTTP response parameters. This means telling the browser what type of document is being returned (e.g., HTML), setting cookies and caching parameters,
and other such tasks.


6. Send the document back to the client. This document may be sent in text format (HTML), binary format (GIF images), or even in a compressed format like gzip that
is layered on top of some other underlying format.