The IP is stored in $_SERVER['REMOTE_ADDR'] while the visitor is on the page.
Users do not have a "Domain Name". Users have "IP" addresses. IP addresses can be obtained in a number of ways; Commonly with dynamic languages, such as PHP; Which can be learned at [ http://www.w3schools.com ].
PHP is a server-side scripting language, which actually has little to do with pixels on your users' computers; so there is no real way to stop pixel bleeding in PHP.
A simple approach would be to log the IP address of each visitor to your website. The IP address identifies the computer or network from where the client visited your website so you should be able to retrace each visitor. In PHP, the IP address of the client is available in the $_SERVER environment variable. $_SERVER['REMOTE_ADDR'];
Yes, a major part of the Internet is web pages that can be viewed using a browser of your choice such as Internet Explorer or Firefox. PHP is one of many languages that can be used to generate dynamic webpages to displayed to website users. Most users of the internet don't write PHP, but they do access pages that are generated using it.
Yes, as the vandals are hurting others, and not just themselves.
IP PBX can be researched on wikipedia. Or, users can search www.fonality.com for more information.
U cant
Static IP address
Nope. If they block anonymous users only, changing ip address will be restricted.
It depends on the technology your web site is using. For example, in PHP you can see this via $_SERVER['REMOTE_ADDR'].
tcp/ip
There are several places where tutorials can be found for query strings in PHP. One is Learning Processing which is good if you are unfamiliar with PHP. Code Diesel has a step-by-step tutorial offering easily followed examples of how to fix query strings. PHP Manuel has a good tutorial for more advanced users.