Three ways to prevent DDOS

DDOS attack, also called denial of service attack simply means creating a massive virtual visitor to a website address at the same time it was intended to "demolish" host storage makes it run slowly or can not run anymore.

A denial-of-service attack (DoS attack) or distributed denial-of-service attack (DDoS attack) is an attempt to make a computer or network resource unavailable to its intended users.

 Method 1: Anti iframe

Code:

Method 2: Anti-reload malicious website
If you are attacked like this, you set up your files .htaccess with the content:

Code:
RewriteEngine on
 RewriteCond %{HTTP_REFERER} !^http(s)?://(www\.)?domain.com [NC]
 RewriteRule !antiddos.phtml http://www.domain.com/antiddos.phtml?%{REQUEST_URI} [QSA]

Then create a file antiddos.phtml with content 

Code:
 $text = $HTTP_SERVER_VARS['QUERY_STRING'];
 $text = preg_replace("#php\&#si",'php?',$text);
 echo("[CLICK HERE TO ENTER]
'');

 ?>

Method 3: Limit number of connections at a time website
You add the following code to the home page of the website.

Code:
function server_busy($numer) {
      if (THIS_IS == 'WEBSITE' && PHP_OS == 'Linux' and @file_exists (  '/proc/loadavg' ) and $filestuff = @file_get_contents ( '/proc/loadavg'  )) {
         $loadavg = explode ( ' ', $filestuff );
         if (trim ( $loadavg [0] ) > $numer) {
             print '';
             print 'Traffic is overloaded, please come back after a few minutes.';
             exit ( 0 );
         }
     }
 }
 $srv = server_busy ( 1000 ); // 1000 is the number of visitors at a time

Read more »