DDoS attacks are increasing not just in number, but also in sophistication, complexity and persistence. REUTERS/Kacper Pempel

This year alone, DDoS — distributed denial of service, to use their unabbreviated infrequently used name — attacks have targeted all sorts of websites and app servers, from games like Warcraft and Pokémon GO, to news websites and even the erstwhile torrent-sharing mecca Kickass Torrents. And if current trends are anything to go by, DDoS attacks are only going to become more sophisticated and complex.

According to a report by network infrastructure company Verisign, Inc., which compiled data for the April-June quarter that went by, DDoS attacks are also becoming more persistent. The frequency of attacks during the quarter was 75 percent greater than the same three-month period last year. The attacks are also larger and more frequent, with 75 percent of attacks peaking over 1 Gbps and a whopping 214 percent increase in average peak attack size, compared to the same quarter last year.

Almost two-thirds, or 64 percent, of DDoS instances used more than one type of attack, showing increasing complexity. While 29 percent used two types of attacks, 16 percent used four or more types of attacks in concert, making them difficult to contain quickly.

The report highlights the growth in the use of Layer 7 attacks. Layer 7 is a low-volume application layer, and attacks that use it usually deploy another, more obvious type of attack to divert the victim’s attention. These DDoS attacks use less traffic but are more effective, since they probe for weaknesses in the code and target them specifically.

The media and entertainment industry was the biggest victim of DDoS attacks during the quarter, followed by the financial industry, a trend continuing from the January-March quarter.