Antispoofing

Antispoofing refers to techniques and practices designed to detect, prevent, and mitigate spoofing, a class of attacks in which an adversary pretends to be someone or something else or falsifies data provenance to gain unauthorized access or mislead a system. Spoofing can occur across multiple domains, including network communications, biometric authentication, and messaging or telephony. Antispoofing aims to verify claimed identities and origins, reduce impersonation, and preserve data integrity.

In network security, spoofing includes IP, ARP, and DNS spoofing, as well as spoofed email or caller IDs. Antispoofing measures include source address validation through ingress and egress filtering, unicast reverse path forwarding, and cryptographic authentication such as IPsec or TLS with proper certificate validation. In routing, mechanisms like origin authentication and route validation help mitigate certain spoofing risks. Anomaly detection and security monitoring also play a role.

In biometrics, spoofing conflicts with presentation attacks where intruders use masks, photographs, fake fingerprints, or voice recordings. Antispoofing, or presentation attack detection, employs liveness cues and multi-modal sensing, such as depth/3D imaging, infrared or multispectral sampling, motion or pulse cues, and challenge–response protocols. When used with high-quality sensors and context-aware verification, anti-spoofing improves resilience, though no system is perfect. Metrics such as false acceptance and false rejection rates are used to balance security and usability.

In messaging and telephony, anti-spoofing includes sender-domain validation and email authentication protocols such as SPF, DKIM, and DMARC, as well as caller-ID authentication protocols like STIR/SHAKEN in many regions. Effective antispoofing typically combines multiple layers of verification, user education, and risk-based authentication to reduce impersonation without excessive friction.