“The internet around the world has been slowed down in what security experts are describing as the biggest cyber-attack of its kind in history. A row between a spam-fighting group and hosting firm has sparked retaliation attacks affecting the wider internet. It is having an impact on popular services like Netflix – and experts worry it could escalate to affect banking and email systems. Five national cyber-police-forces are investigating the attacks. Spamhaus, a group based in both London and Geneva, is a non-profit organisation which aims to help email providers filter out spam and other unwanted content. To do this, the group maintains a number of blocklists – a database of servers known to be being used for malicious purposes. Recently, Spamhaus blocked servers maintained by Cyberbunker, a Dutch web host which states it will host anything with the exception of child pornography or terrorism-related material.”