Inbound traffic is data flowing into a network, device, or online service. It includes ordinary activity such as users loading a webpage, as well as automated requests, misdirected traffic, and potentially malicious activity. A rise in inbound traffic is not, by itself, evidence of an attack.
In cybersecurity, defenders examine traffic volume, sources, timing, and request patterns to distinguish normal demand from overload or threats. During a denial-of-service attack, excessive inbound requests may consume bandwidth or system resources and make services unavailable. Monitoring network and application logs helps responders assess what is happening; rate limiting, traffic filtering, and upstream traffic scrubbing can reduce harmful load while preserving legitimate access.