Hackers are on the prowl, and there are no signs that their hunting is slowing down.

In its latest State of the Internet report, Akamai Technologies AKAM , which helps companies serve their sites and digital content to the public, says that the number denial of service attacks against company websites and services in the fourth quarter rose 40% compared to the previous quarter. Such attacks, which involve hackers using thousands of computers to overload websites, rose a whopping 149% compared to the fourth quarter of 2014.

Meanwhile, hacker attacks against corporate Internet-based software grew 28% compared to the third quarter, the company found.

Akamai’s findings are based on attacks on its own customers, which include a number of major companies. Akamai didn’t say how many of its customers were targeted, but it did say that it “mitigated” 3,600 denial of service attacks in the fourth quarter, alone.

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The State of the Internet Report provides detailed information about the threats companies face in a world in which hacking is a perpetual threat. The report details not only how many attacks its customers faced, but also from where they originated and the methods the hackers used.

In July, for instance, New York Magazine’s web site succumbed to an attack by the hacking group, Vikingdom, which said it chose its target because it doesn’t like New York City. In December, hackers threatened gaming networks Xbox Live and the PlayStation Network by saying that they would use denial of service attacks to stop users from playing games online. Those attacks never materialized to the degree the hackers, Phantom Squad, had hoped. Still, the threat was part of a broader trend affecting many U.S. companies.

According to Akamai, 54% of all denial of service attacks in the fourth quarter targeted gaming companies. Another 23% of those attacks took aim at the software and technology industry. Akamai said that attacks on software were predominantly used against the retail industry. Retail companies accounted for nearly 59% of that kind of attack. Akamai didn’t say why retail was such a prominent target, but as recent hacks on major retailers have shown, stealing credit card information could have been a focus.

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“The threat from DDoS and web application attacks isn’t going away,” Stuart Scholly, a senior vice president and general manager for Akamai said in a statement, using the acronym for denial of service attacks. “Each quarter, the number of attacks against Akamai customers continues to surge.”

He added: “And malicious actors aren’t backing down. They’re hammering away at the same targets over and over again, looking for a moment when defenses may be down.”

Looking ahead, however, at least Google GOOG hopes to turn the tide. Last week, the tech giant unveiled Project Shield, a service that helps stop hackers who want to use denial of service to take down websites.

The idea, currently being tested with human-rights sites, makes Google the site’s web host. When a denial of service attack is recognized, Google’s own internal infrastructure would kick in and blunt the attack before it takes down a site. It’s unknown if any organizations have taken Google up on its offer or how successful Project Shield would be in fighting off a sophisticated attack.

What is clear, however, is that hackers aren’t looking to slow down.