DoS vs DDoS – What Is The Difference?

DoS = Denial Of Service

DDoS = Distributed Denial Of Service

What is the difference between the two?

Dos vs DDoS attack

Whilst DoS and DDoS sound remarkably similar there are in fact differences between the two –


A DoS Attack is a Denial of Service attack.

This means that one computer and one internet connection is used to flood a server with packets (TCP / UDP). The point of such a denial of service attack is to overload the targeted server’s bandwidth and other resources. This will make the server inaccessible to others, thereby blocking the website or whatever else is hosted there.


A DDoS Attack is a Distributed Denial of Service Attack.

In most respects it is similar to a DoS attack but the results are much, much different. Instead of one computer and one internet connection the DDoS attack utilises many computers and many connections. The computers behind such an attack are often distributed around the whole world and will be part of what is known as a botnet. The main difference between a DDoS attack vs a DoS attack, therefore, is that the target server will be overload by hundreds or even thousands of requests in the case of the former as opposed to just one attacker in the case of the latter.

Therefore it is much, much harder for a server to withstand a DDoS attack as opposed to the simpler DoS incursion.

About Lee Munson

Lee's non-technical background allows him to write about internet security in a clear way that is understandable to both IT professionals and people just like you who need simple answers to your security questions.


  1. Asianricedude says:

    I just did a DoS attack, sent 65500 bytes, did practically nothing Lol.

  2. A Reader says:

    “In most respects it is similar to a DoS attack but the results are much, much different.” How are the results different? Just because multiple nodes are participating in A DDOS doesn’t mean the result is any different, they both lead to a denial of service don’t they?

    • Indeed they do. The difference is that a DDoS is typically harder to mitigate against.

    • The difference is that one would be harder to prevent – the outcome is the same obviously, just the process is what he meant.

      • Also, from my experience, a host can easily block a DOS, but prolonged DDOS will often cause them to cancel your hosting plan or require that you move to a dedicated server, and for smaller sites this can get pricey.


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