Distributed Denial of Service
A distributed denial-of-service (DDoS) attack uses many systems to overwhelm a target and degrade availability.
Senses
Distributed availability attack
DDoS attacks distribute traffic or requests across many sources (botnets, reflected/amplified traffic) to saturate bandwidth or exhaust application resources. Defenses include upstream filtering and traffic engineering.
References
- NIST CSRC GlossaryJan 05, 2026NIST CSRC Glossary — Distributed denial of servicehttps://csrc.nist.gov/glossary/term/distributed_denial_of_serviceNIST states most site information is public information and may be distributed or copied, except material marked as copyrighted; attribution requested. Verify per-document markings before quoting.Source: NIST CSRC Glossary (csrc.nist.gov).
Sense 2
A denial of service technique that uses numerous systems to perform the attack simultaneously.
References
- NICCS (CISA) Cybersecurity VocabularyJan 06, 2026NICCS glossary export (CSV)https://niccs.cisa.gov/rest/vocab/export-csvNICCS is a CISA (DHS) program. Individual glossary entries include a "From" attribution (e.g., CNSSI 4009, NIST SPs, NICE Framework). Treat "From" values as upstream provenance and verify before quoting large portions of text.Source: NICCS (CISA) Cybersecurity Vocabulary (niccs.cisa.gov).