denial of service attack

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denial of service attack

An assault on a network that floods it with so many requests that regular traffic is either slowed or completely interrupted. Unlike a virus or worm, which can cause severe damage to databases, a denial of service attack interrupts network service for some period.

Distributed Attack
A distributed denial of service (DDOS) attack can employ hundreds or even thousands of computers that have been previously infected. The computers act as a network of "zombies" working together to send out bogus messages, thereby creating huge volumes of phony traffic.

In 2016, the Dyn DNS system was hammered by a DDOS attack that caused sporadic slowdowns of major sites such as Twitter, Netflix and The New York Times. The zombie traffic reached more than 100 gigabytes per second of bogus messages. See botnet, smurf attack, SYN flood attack, land attack, teardrop attack and Ping of Death.

It's Not a New Phenomenon
In February 2000, computers were activated that had been previously hacked and planted with illicit programs. The unending number of requests caused a denial of service at Yahoo, eBay, and other websites. (Article headline courtesy of the Philadelphia Inquirer.)
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References in periodicals archive ?
The analysis of commands received by bots from command and control (C&C) servers revealed that the longest DDoS attack of Q2 2019 lasted 509 hours -- almost 21 days.
The quarterly report, which measures thousands of DDoS attacks around the world, revealed DNS amplification attacks were also the most frequently employed against CSPs and telcos in Brazil this quarter.
Communications service providers who rated their DDoS defense capabilities highly were more likely to have sound intelligence into global botnets and weapon locations.
Any doubt about the scale of the threat posed by Distributed Denial-of-Service attacks is swept away by looking at A10 Networks' "DDoS Weapons Intelligence Map".
Earlier today, the National Cyber Security Agency had warned of cyberattacks, including those of a DDoS nature, on government and private organisation websites.
Tactics for DDoS attacks are moving beyond just using request floods designed to bombard and overwhelm infrastructure to include low-bandwidth attacks that target the network or application layer of service provider services and their subscribers.
Just this month, BitConnect, a cryptocurrency lending and exchange platform, announced it would shut down, and partially said a string of website paralysing DDoS attacks contributed to its closure.
The largest volumetric DDoS attack observed by Verisign in Q3 2017 was a multi-vector attack that peaked at approximately 2.5 Gbps and around 1 Mpps for one hour.
The Russian company DDoS-GUARD LTD, a licensed communication operator specializing in protection against DDoS attacks and successfully working on this market for more than 6 years, was selected as a provider of protection services.
The email, sent to, claimed that if the site didn't remove a document involving one of Jahanrakhshan's cases then the site would be targeted by a DDoS attack that would result in visitors being unable to access the site.
The Russian market for protection against DDoS attacks is far from saturation, and by the year of 2020 its volume is about to reach $ 32 million with average annual growth rate of 14.4%.