An intrusion detection system begins receiving an abnormally high volume of scanning from numerous sources. Which evasion technique does this attempt indicate?

Traffic fragmentation splits attack payloads into small packet fragments to prevent the IDS from matching complete attack signatures, and does not rely on high-volume scanning from multiple sources.

Resource exhaustion is an IDS evasion technique where the attacker intentionally generates an overwhelming volume of traffic or events from numerous sources to saturate the IDS's processing, memory, or logging capacity. When the IDS is overloaded, it drops packets or events it cannot process, creating blind spots that the attacker can exploit to launch the real attack undetected. The use of numerous sources distributes the load and makes the flood harder to filter by single-source rules.

A timing attack slows down malicious traffic to fall below the IDS's time-based detection thresholds, which is the opposite of generating abnormally high volumes.

Tunneling hides malicious traffic inside legitimate protocols such as DNS or HTTP to evade signature-based detection, and is unrelated to volumetric scanning floods.