Around 1:30 pm ET on Tuesday afternoon, Canadian government websites became inaccessible due to a denial-of-service attack, The Globe and Mail reported. The attack affected industry, employment, national resources, fisheries and oceans, justice, labor, foreign affaisr, environment and transportation related websites. A denial-of-service attack, sometimes called a DOS attack, occurs when hackers flood a website with traffic, essentially leaving it unusable to normal users hoping to browse the site. It is unclear why Canada’s government websites faced this attack or who the hackers are. Source: http://www.newsweek.com/canadian-government-websites-inaccessible-following-denial-service-attack-344002

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Canadian Government Websites Inaccessible Following DDoS attack