Twitterwasdowned by a DoS attackyesterday and
took nearly three hours to restore services after it experienced
connectivity problems.
Business and other users were unable to access the microblogging
site for at least 90 minutes as Twitter scrambled to deal with the
problem.
Twitter and other companies including Facebook companies were
victims of "a single, massively co-ordinated attack," according to
blog post by Twitter co-founder Biz Stone.
Facebook encountered network issues related to an apparent DoS
attack that resulted in degraded service for some users, the
company said in a statement.
Both Twitter and Facebook emphasised that no user data was at
risk as unknown attackers flooded the sites with requests to block
legitimate users.
Twitter is working with other companies to investigate the
attack.
Stone said Twitter had worked hard to achieve technical
stability, but yesterday's globally distributed attack was a
reminder there remains a lot of work ahead.
Tony Dyhouse, director of the
Cyber Security Knowledge Transfer Network, said the threat of
malicious attack needs to be considered when running a business
which demands a continuous online presence.
"Cyber attacks can lead to a loss of revenue and a damaged
reputation," he said.
Paul Vlissidis, director at NCC group's Secure Test, said DoS
attacks were becoming commonplace.
"The fact that Twitter said that it was 'defending' the attack
suggests that it was malicious. Popular websites have to factor DoS
attacks into their security strategies, as it doesn't look like
they're going away any time soon."
There is little these sites can do against a well organised
denial of service (DoS) attack, said Tony Dyhouse.