.htaccess is a unique file and Preventing Bandwidth that performs the necessary functions at the time when browser sends your web server a request for your resources.
Bandwidth theft happen in many cases when some other people uses your resource path into their sites with out your prior permission. They can use your images, your zip contents and some other resources into their sites. There is a way to block this situation and to redirect people that try to access your resources files directly to your website. What you need to have a .htaccess file in your root directory, and then you need to paste the following code in that file. Note that the name starts with a fullstop (or period) and is entirely in small letters (ie, lowercase). Cut and paste (unless you're using IE 6 in which case you just have to type it yourself) the following lines into that file, either first one or the second one.
RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://(www\.)?sitename.com(/)?.*$ [NC]
RewriteRule .*\.(gif|jpg|jpeg|bmp)$ http://www.sitename.com [R,NC]
or
SetEnvIfNoCase Referer "^http://www.your-domain-name-here.com/" locally_linked=1
SetEnvIfNoCase Referer "^http://www.your-domain-name-here.com$" locally_linked=1
SetEnvIfNoCase Referer "^http://your-domain-name-here.com/" locally_linked=1
SetEnvIfNoCase Referer "^http://your-domain-name-here.com$" locally_linked=1
SetEnvIfNoCase Referer "^$" locally_linked=1
<FilesMatch "\.(gif|png|jpe?g)$">
Order Allow,Deny
Allow from env=locally_linked
</FilesMatch>
The above file should protect all images that have ".gif", ".png", ".jpg" and ".jpeg" extensions.
Note
Remember to use an ASCII text editor (also known as "text editor" or "plain text editor") to create the .htaccess file. Do not use Microsoft Word or Wordpad. Notepad (found on all Windows systems) is fine.
After you create the .htaccess file, if some other site tries to link to your image from their site, they will find that the image will not display on their site. On the other hand, your images should generally load fine on pages on your site.
How does it works
Whenever a browser sends your web server a request for an image, it usually also sends the URL of the page that linked to that image. The above .htaccess file causes the server to check URL and if it is one of the authorized URLs that you specify, it will set an internal flag called "locally_linked". This internal flag is technically called an "environmental variable". If the URL sent is not in this list of authorised URLs, the flag (or environment variable) is not set. Note that we also set the "locally_linked" variable if the browser does not send any URL at all: this occurs when the visitor accesses your site using a browser or a proxy that suppresses the referring URL.
The web server then checks if the file requested has an extension in the list given above (gif, png, jpg and jpeg). If so, and the "locally_linked" variable is set, it will send the image. Otherwise it an error will be sent.
Use it first
In addition to using the .htaccess file to protect your images, you may also want to send the offending webmaster an email and/or a letter explaining that he/she is violating your copyright and asking him/her to stop the infringing practice. Sometimes that simple message would more than suffice.
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