Furthermore, it may persist in directing all ISPs to block traffic to that particular IP address - although this would serve no functional purpose. Effectively, the ABA would be banning the IP address of a modem belonging to an ISP and not the web site. Presumably, the ISP could then identify and delete the offender's account. A typical 'Warez Puppy' or porn site owner could use other people's accounts to achieve their ends. An ISP could block incoming Internet traffic to port 80 on its computer system by using a firewall.
Different ports facilitate different Internet services.
Port 80 is the standard port used by ISP's and ICH's to facilitate web servers. The effect of blocking port 80 would be to prevent a person from placing their Web Site on the InterNet. The main problem with word filters is that they are too simplistic. Words are used in many contexts, so filtering software often results in blocking people's access to thousands of highly useful, valuable and legal sites. As filtering software searches for text embedded in the web site's HTML code, a site with harmless text, yet plenty of offensive graphics, audio files and movies, will escape the filters.