A denial of service attack is a deliberate hostile attempt to make an online system unavailable to its intended users today.
Intent distinguishes the attack from an outage caused by a fault or by ordinary demand that the system was never built to meet.
How it works
The attempt may come from one source or from many, and it succeeds when intended users cannot complete the work the service exists to do.
Describing that intent does not require publishing the technique, the traffic pattern to copy, or commands that would repeat it.
Response prioritizes restoration and evidence preservation over public speculation.
Operators filter with their providers, protect critical paths, and record timing, while detailed methods stay in a private incident record.
Concrete examples
- A charity donation page is deliberately overwhelmed on the morning of a public appeal, and donors cannot pay.
- A single hostile source opens so many connections that a small service stops answering its regular clients.
- Operators confirm intent from the timing and the target, then restore service without describing the method in the customer notice.
Protective measures
- Treat a suspected availability attack as an incident with an owner, a clock, and a goal of restoring users first.
- Use your provider's filtering arrangements, and do not experiment with untried changes on the live service during the event.
- Preserve timing and volume evidence for later review without putting reproduction detail into customer messages.
- Afterward, note whether the attempt was concentrated or distributed so the follow up matches the right companion control.