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I read here:

Network bandwidth is the capacity of a network communications link to transmit the maximum volume of data from one point to another over a computer network or Internet connection in a given amount of time, usually one second. Bandwidth has the same meaning of capacity, and defines the data transfer rate.

Does this mean that the higher the bandwidth, the (generally) more likely that your router can withstand a DDoS?

And what is a typical bandwidth (in Gbps) that most routers have? If someone stresses my router with a 1Gbit/sec attack, how much bandwidth (or whatever it is that an attack’s effectiveness depends on) would I need to withstand it with 0 issues? If it doesn’t completely override my router to the point that it’s useless, would it give me lag or something?

NOTE: if there’s a better SE I could ask this on, please redirect me to it

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    This is probably better suited for security.SE? Or maybe networkengineering.SE, but this is probably a bit tangential there...
    – jcaron
    Apr 6 at 7:30
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There are many forms of (distributed) denial of service attacks. If some are based just on bandwidth, many will impact the service way before any link is saturated.

If any request sent to your server(s) takes 100 ms of CPU time to execute, for instance, each CPU/core will at most be able to process 10 such requests per second. Even if you have 10 servers with 8 cores each, then 800 requests per second will saturate your infrastructure. Even counting 10 KB per request, that’s just about 64 Mbit/s. Even if you have Gbit/s links everywhere, your service will still be unavailable or very slow.

Others may saturate your servers by just keeping connections open. They don’t even need to use any CPU, just keep the connection open as long as possible. Depending on the server software and settings, this may bring your service to a halt quite quickly.

So it all really depends on the type of attack and the servers and their setup.

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