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DDoS FAQ: Frequently asked questions about DoS and DDoS denial of service attacks

What is a distributed denial of service (DDoS) attack?

A denial of service (DoS) attack or distributed denial of service DDoS attack is an attempt to make a computer resource (i.e. – web site, email, voice or an entire network) unavailable to its intended users.

How does a DDoS attack bring down a web site?

By overwhelming a web site and/or server with data and/or requests, the target system either responds so slowly as to be unusable or crashes completely. The data volumes required to do this are typically achieved by botnets, which are networks of remotely controlled infected machines known as zombies.

Who controls these DDoS botnets and how many are there?

Botnets fall under the control of a DDoS denial of service attacker, generally through the use of Trojan viruses. Prolexic currently tracks more than 4,000 command and control servers, which manipulate these botnets for DDoS attacks, and we track more than 10 million bots in our global IP reputational database. Some DDoS experts estimate that one quarter of Internet-connected computers are part of a DDoS botnet.

Should I be worried about DDoS?

Because Internet-facing infrastructures are critical to the profitability of most organizations, the impact of a DoS or DDoS attack can be catastrophic and widespread – affecting your ability to communicate, process transactions or function effectively for hours or even days. On average there are more than 7,000 distributed denial of service (DDoS) attacks observed daily – a number which is growing rapidly.

If my site goes down due to a DDoS attack, how much revenue could I lose?

It all depends. If the purpose of your site is primarily to provide information, financial loss may be minimal. On the other hand, if your site is an e-Commerce engine that drives revenues, your losses due to a DDoS attack could be significant. For example, industry analyst firms estimate the cost of a 24-hour outage for a large e-Commerce company can approach US$30 million.1

Would anyone really want to DDoS attack our company?

Some DDoS targets are obvious: online gaming sites, financial services firms, and payment processors, for example. But we are learning that any company or web site could be a target. In the cyber underworld, it is possible to rent 80,000 -120,000 hosts capable of launching distributed denial of service (DDoS) attacks of 10 to 100Gbps – more than enough to take out practically any popular site on the Internet for just US$200 per 24 hours.

What if I already have a provider of DDoS mitigation services?

Many network or Internet-related service providers offer DDoS mitigation capabilities, and you may be using those already. However, most of these firms rely primarily on automated tools and have limited network capacity to absorb large DDoS denial of service attacks.That’s why many companies eventually find their way to Prolexic. With the largest DDoS protection and mitigation network , proprietary tools, and skilled anti-DDoS technicians who can react in real-time to changing DDoS attack characteristics, we can overcome any denial of service attack. That’s why DDoS attacks end here.

What is an application Layer 7 DDoS attack?

Lately, more and more DDoS hackers have been adding complex Layer 7 DDoS attacks that resemble legitimate traffic. In 2010, 40% of denial of service attacks mitigated by Prolexic included at least one Layer 7 component. Unlike more common regular bandwidth floods, Layer 7 DDoS attacks can be structured to overload specific elements of an application server infrastructure. Even simple DoS attacks – for example those targeting login pages with random user IDs and passwords, or repetitive random searches on dynamic web sites – can critically overload CPUs and databases. Prolexic is the only DDoS protection provider able to mitigate and clean SSL post and GET Flood DDoS attacks.

How quickly can Prolexic get our site back up?

Depending on denial of service attack type, Prolexic can typically provide protection and DDoS mitigation time in just 5-20 minutes after traffic starts to flow through Prolexic’s traffic scrubbing centers .

How do I get more information on Prolexic’s DDoS protection services?

If you’d like more details about our cloud-based DDoS detection and mitigation services for DDoS protection, do one of the following: visit our Knowledge Center, complete this form or call us at + 1 (888) 368 2923.

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