Just 20 Internet Service Providers (ISPs) out of over 42,201 are responsible for spreading 50 percent of junk mails, phishing attacks and other malicious messages, a survey has revealed.
The survey by a researcher in Holland found that many of these networks were concentrated in India, Vietnam and Brazil.
On the net's most crime-ridden network, Spectranet in Nigeria, 62 percent of all the addresses controlled by that ISP were seen to be sending out spam, the BBC reports.
According to the report, in his analysis of over 42,000 ISPs, Giovane Cesar Moreira Moura who studied at the University of Twente, found that some networks could be classed as "bad neighbourhoods" because, just like in the real world, they were places where malicious activity was more likely.
Moura discovered that networks involved in malicious activity also tended to specialise in one particular sort of malicious message or attack.
For instance, the majority of phishing attacks came from ISPs based in the US, the study said.
By contrast, spammers tend to favour Asian ISPs. Indian ISP BSNL topped the list of spam sources in the study, it added. (ANI)