The number of application layer distributed denial-of-service (DDoS) attacks has declined in the second quarter of 2012.

According to Prolexic, it has detected an eight per cent decline in application layer DDoS attacks, which accounted for 19 per cent of all attacks in that period in comparison with the first quarter of 2012. The total number of DDoS attacks increased by ten per cent in that quarter.

In comparison to the second quarter of 2011, there has been a 50 per cent increase in total number of DDoS attacks and an 11 per cent increase in infrastructure (layer three and four) attacks.

Stuart Scholly, president of Prolexic, said: “With layer seven attacks, the risk of detection and eventual take down by law enforcement increases because these attacks disclose the IP address of the attacking botnet and this may be another reason for their decline this quarter.

“If your internet-facing infrastructure is critical to business operations, you'll need a DDoS mitigation service that can block volumetric infrastructure attacks, but also all application layer attacks, including HTTPS, GET and POST floods.”

The report also found that China was the top source for sending DDoS attack traffic.

Speaking at an event in London, Aftab Afzal, EMEA sales manager at Prolexic, said that China had been in the top spot for the last two quarters.

“DDoS attacks are done by botnets so it is not attributable to China, it is just that there are more users in China and therefore more users and more infected machines,” he said.

“We do see other attacks against other targets; this is also one of the few areas where there are attacks between competitors.”