Aug 16, 2010 15:33 GMT  ·  By

Virgin Media, one of the biggest Internet service providers in UK, plans to start sending warning letters to customers if their computers are infected and are generating botnet-related traffic.

The Register reports that Virgin will start scanning lists of compromised hosts maintained by the Shadowserver Foundation and other botnet tracking organizations for IP addresses assigned to its customers.

Botnets are armies of computers infected with malware, which hackers can control remotely via command and control (C&C) servers or distributed peer-2-peer networks, depending on their infrastructure.

Botnets are very versatile and provide their runners with many economic prospects, like selling Distributed Denial of Service (DDoS), spam or pay-per-install services to other cybercriminals.

Virgin Media plans to begin its campaign by sending several hundred letters per week to see how customers react and then scale their effort as needed.

The letters will contain links to download free anti-malware software and instructions for customers to attempt cleaning their computers on their own.

However, if this proves too much for their level of computer knowledge they can opt for the already existent £6/month Digital Home Support service offered by the company.

According to Virgin a significant number of people who already use the helpline are calling to deal with malware infections, so the technicians working there are used with such cases.

Security experts have long argued that ISPs should take a more active role in helping customers deal with computer threats, since they are uniquely positioned to identify the origin of bad traffic on their networks.

In October last year, Comcast, the largest residential cable and Internet service provider in the United States, began testing a system to alert its customers of malware infections via in-browser notifications.

The German government is also working with the country's Internet industry association (eco) to have all ISPs begin identifying infected computers and direct their owners to resources that would help them deal with the problem.

The plan also involves creating a government-funded call center where forty IT specialists will be available to assist Internet users who can't clean their computers on their own.