The potential disruption of service and risk posed by compromised, zombie PCs spewing spam is putting fear in UK ISPs, according to a survey conducted by security firm StreamShield Networks.

A massive 96 per cent of 50 ISP respondents cited the proliferation of botnets - networks of virus-infected PCs under the control of hackers - as a key business issue.

According to industry analyst firm Gartner, seven in 10 items of spam originate from infected PCs.

Other items high on the agenda include the difficulties ISPs face in differentiating services from competitors, finding fresh sources of revenue, and addressing user concerns about the security of their services.

Bandwidth optimisation, customer churn, falling margins, and the negative impact on service resulting from traffic in spam and malware also got a mention in the StreamShield survey, conducted during a recent meeting of ISP peering organisation LINX.

On a more positive note, ISPs recognised that customers would be prepared to pay a premium for security filtering services, a handy result for SteamShield, which supplies kit designed to block spam and viruses. ®