What is AI Firewall?
TL;DR
A dedicated security layer guarding LLM apps against prompt injection, data exfiltration, and toxic outputs. Lakera, Protect AI, CalypsoAI lead the 2026 market.
AI Firewall: Definition & Explanation
AI Firewall is a security layer that inspects LLM I/O for (a) prompt injection, (b) jailbreaks, (c) PII / secret leakage, (d) toxic generation, (e) data extraction, (f) indirect prompt injection (instructions hidden in documents or URLs). Common implementations: (1) Lakera Guard ($50-2,000/mo, prompt-attack focus), (2) Protect AI (MLOps + AI Firewall), (3) CalypsoAI (enterprise GenAI governance), (4) Cloudflare Workers AI Firewall, (5) AWS Bedrock Guardrails, (6) Azure AI Content Safety, (7) NVIDIA NeMo Guardrails (OSS), (8) Google Cloud Model Armor. Layers: (I) input scan — known jailbreak patterns (DAN, role-play), indirect injection from URLs, PII / code, (II) output scan — toxic content, PII leakage, jailbreak success detection, (III) audit logging — SOC2 / GDPR / EU AI Act, (IV) policy engine — topic restrictions, keyword blocks, custom rules. OWASP LLM Top 10 (LLM01: Prompt Injection, LLM02: Insecure Output Handling, etc.) is the reference. 2026 drivers: EU AI Act enforcement makes AI Firewall essentially mandatory for High-Risk AI (fines up to €35M); US NIST AI RMF and FedRAMP alignment; multi-agent firewalls (inter-agent communication monitoring); pairing with Constitutional AI; on-device firewalls (Apple Intelligence). Required for healthcare, finance, legal, education, and government GenAI; multi-layer with Constitutional AI for defense in depth; expect 50-200ms added latency.