3

What would happen if you have an access layer switch with a 10 Gbps uplink and 1 Gbps downlinks and 1 machine (behind one of the 1 Gbps ports) would be attacked by a 10 Gbps UDP flood type attack? Will the switch accept the whole 10 Gbps of traffic and pass only 1 Gbps to the downlink and have its uplink saturated or only let 1 Gbps pass through, so that the uplink isn't congested (10% used)? I'm trying to find out what would happen in case a 10 Gbps network attack targets one machine connected at 1 Gbps to a switch having a 10 Gbps uplink. Thanks.

1
  • Did any answer help you? if so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer.
    – Ron Maupin
    Aug 12, 2017 at 5:13

2 Answers 2

2

In a typical scenario, the switch has no way to tell the upstream device to stop sending it so much. So it will receive 10Gbps from upstream. Obviously it can only send 1Gbps downstream. So it will send 1Gbps downstream. Of the remaining 9Gbps, a few packets will probably be buffered and the rest will be dropped by the switch.

1

The switch will accept up to the interface speed from an interface*. Switches have very tiny buffers. With 10 Gbps of traffic going to a 1 Gbps interface, 90% of the traffic will be dropped at the 1 Gbps interface.


*There are cases where this may not be possible. For example, a switch with an ASIC that serves an interface, but the ASIC can't handle the full traffic.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.