The Government encourage people who are inadvertently exposed to child abuse images to report the URL to the Internet Watch Foundation (IWF). Ninety-five per cent, of consumer broadband connections are now covered by blocking, based on the IWF's list of known child sexual abuse URLs. Since 2004, blocking of these sites on consumer broadband in the UK has gone from nothing to 95 per cent. thanks to the work carried out by industry and the IWF. The number of sites hosted in the UK, potentially containing child abuse images is less 0.4 per cent., down from 18 per cent. in 1997.
There are difficulties in removing sites which originate outside of the UK's jurisdiction. The IWF 2007 annual report shows the longevity of some child sexual abuse sites and how they avoid detection by moving servers. This is a challenge for law enforcement because these sites hop between jurisdictions to avoid being closed down.